I am looking at heat pumps but i live in a BISF house that has been externally insulated early 2005 the question is it worth me looking at this form of heating alternitive to gas
Thank you so much. Your short video summarised everything I have learned over the last 2 years since my heat pump was installed. You have clearly explained everything I have been doing wrong, and why my SCOP is only 2.2. I might even ask my wife to watch the video!
Thank you so much for this video. Just turned my weather compensation on after it being set to a flat 40 flow temp by the installers 4 years ago. I didn't dare touch it until watching this. Hopefully the on/off cycling will cut down considerably. I have a very low cost 1.30am to 6.30am tariff so actually 'charge' up my floor slab during these hours which normally means the heat pump doesn't kick back in until about 2pm when it's cold outside. It seems to work well solar and home battery usually meaning I don't have to use any high rate electric at all. Might not be the most efficient but it's definitely the cheapest and also gives me a lovely warm floor first thing in the morning :)
Very good explanation which confirms what some others have been telling me. Did a test of WC and then constant 45c flow temp but only over a couple of days and no diff on energy consumed or cop but need to check over a longer period, especially as temps always diff. Please, please, please drop the music background though, it is very distracting when trying to concentrate. Thanks!
Great video. Because of the info found here and other Heat Geek videos I fined tuned my system, quit zoning, no setback temps. My setup is Vaillant turbotec plus combi boiler, 12 year old, 28 KW (non condensing), 8 rads (3 - 1200x400; 4 - 1400x600; 1 -1600x600), 22 type +1 towel rail, in a single series loop, controlled by Tado thermostat with all functions active, connected and configured for ebus protocol. I`ve got a detached 70`s old brick build, 125 m2, thick walls, 450-500mm, concrete floors covered with timber board, both uninsulated; loft has 200mm mineral wool insulation, except a room; double glazing doors and windows. I heat 24/7 at 22,7 C, no setback temp, no zoning, all TRV`s are fully open. I consumed 18 mc3/day, 10 EUR/8.6 GBP (10.01.), with an average outside temp of -3C throughout the full day. Tado modulates the flow of the boiler at somewhat low temperatures 42-52C, for the example above, (the boiler does cycle) and when it`s slightly warmer (0 to 5 C outside) between 38 -46C flow; on a sunny day 36-44C flow. Considering this operation mode do you think I could switch to a condensing boiler or save it for a major renovation I am planning in 2-3 years’ time (full insulation, underfloor heating, may be a heat pump)? Thank you and i hope you extend your heat geeks network outside UK, in the future. Love your work. Greetings from Romania
I had homeserve fit my Worcester 4000 the fitters left the boiler in the highest settings thank god for heat geek thank you now I have cheaper bills and a warmer home 👍
Wow! Thank you so much for your informative videos. I wish i had seen them a year ago. I had a heat pump installed in June, along with wall insulation, new radiators and solar panels. This was all under the ECO4 scheme, and when the company first came he said that an ASHP would definitely save me money. I live in rural Scotland and was using oiul for heating. The work took two months to complete, and afterwards the house was very comfortable. In September my electric bill rose to £139, which was bearable, but in October it rose to £283! Now I am really worried that the colder months will cost a lot more, and this indicates that the new system will not be saving me money after all. Having watched this video and checked some settings, I now know that the ASHP is not set to weather compensation and they have also given me two zones, each with an external thermostat. I have thermometers in each downstairs room, and the temperatures recorded are not good, with one room as low as 12 degrees, even though the zone thermostat is set to 17 degrees. None of the rooms are recording 17 degrees (15 degrees is the highest). The thermostats do change at different times of the day, and I now believe this could be an important issue, so I plan to change the unit to weather compensation and change the thermoststs to a static temperature all day. I hope this will make us more comfortable and reduce the costs. If not, I will be forced to look at other solutions, as I am a pensioner and cannot afford extremely large electric bills. Maybe I should have only got the solar panels and insulation. Maybe my oil bills and my electric bills will have both reduced.
Thank you very much for providing this information. I recently moved into a new home with GSHP and had no idea how to utilise it effectively. With this knowledge, I intend to operate a more efficient system. One thing I don't understand is the degree minute setting. Currently, it is set to -60DM. Every 60 minutes, the compressor appears to cycle off and on. The compressor appears to heat up more than the projected flow temperature. Current configurations Current Value 100DM Start Compressor -60DM diff. between additional steps 100DM
Background music on auto gain is a no no, so distracting. Information is great and on point, spoilt by background music. It's really not needed unless you are in a lift.
@@HeatGeek Damn I must be an older person! I don't mind background music if it doesn't intrude, but you can hold a stage with your content without needing gimmicks. Thanks for producing the video.
I have an Ecodan system that works fairly well (except Mitsubishi think that it is OK for it to totally ice up for 20 minutes before a 2 minutes defrost cycle) and is reporting a SCOP of 5.0 in a very old house. My cunning plan varied the compensation curve every two weeks, plotting the amount of time the system ran against daily average outside temp. I kept dropping the curve until the system ran between 80 and 95 percent of the time. I have trialled fitting low speed computer fans under the two or three layer rads to compensate for the lack of convection at low temps and this has worked very well, with the particular rad turning off more often. These use about 5W total for a 1.5m triple layer rad, and are controlled by a cheap programmable temperature sensor, and I reckon that I will be able to drop the temp by about 2 degrees when I roll them out through the house. A commercial system reports 20% higher output with fans, but those were expensive, and the small high speed fans made the fins in the rads sing. I am also trying polycarbonate secondary glazing to reduce heat loss, and also allow lower delivery temps, with our 200 year old windows. Not that I am obsessed of course.
Blooming great information as usual, and lovely to hear the talk about removing setback as much as possible. Would love to spend some time with you on understanding zoning. Our advice to customer is that zoning (when done correctly) allows for the comfort in each room to be controlled, i.e. your bedrooms can be controlled lower than living areas, under the number 1 rule of continual operating conditions. (mainly talking UFH but does apply to rad's as well). This can also help protect against solar gain a little in south-facing areas. But if removing demand affects the COP, we want to make sure the advice is spot on and harmonious with the rest of the industry.
I'd say the purist answer is firstly to try and balance room heat losses & gains using additional insulation and window shading, based on calculations. But as the vid explains in all cases make sure all emitters (underfloor or radiators) are sufficiently sized and correctly balanced to each room load. Then the house should heat fairly evenly without falling back on zone controls. If room losses/gains have large differences and emitters are not balanced you generally end up with the highest loss zone over-driving the the whole system which wastes energy.
Fantastic video. I appreciated the idea of lower flow temperature for your ASHP equals better efficiency. But I hadn’t understood the logic behind it - balancing heat demand to heat loss whilst keeping your room at a comfortable temperature. Brilliant explanation. I will be sharing the video and testing the logic with my ASHP. Thank you
Great and clear video! How I wished to have such simple system :) When you add two floors, wooden flooring(limit temp to 40C max), undergrounf water heating and Nest control of one zone, do not know what degree is needed to balance the system ..
Surely one's energy bills have the info needed to calculate a house's insulation performance. I use them to work out how much energy our house uses across the year. Mine needs improving before I can consider a heat pump as an alternative to gas boiler. What I will need is to know how to work out the best way to improve it. In my opinion, this specialist expertise is what will be most needed before 2030. The right answers for my house are not obvious.
No because it could be a really poorly installed system.. crap cylinder.. High gas cooking.. also does not shown the relative size of rads. Its needs a survey.
@Heat Geek OK about some aspects of poor installation, such as a heating system that doesn't provide enough heat when on all of the time. Fitting a heat pump that cannot output enough heat to an inadequately insulated house creates that problem as you have said elsewhere. OK about boilers that shove heat up the chimney too. Being indoors or within one's living space, poor quality cylinders probably give out their wild heat to a nearby room (where the heat is not used to heat water). I should add a caveat around households that cannot afford to heat the home to a comfortable level all of the time. The true heating requirements would be understated in bills. Add an adjustment or a caveat about houses that are not occupied all of the time covered by the energy invoices.
Yes of course, the higher the energy consumption on the bills the more important it is to improve energy efficiency of the building and thus have the comfort without wasting money. The choices and specification of these insulation improvements is best done by specialist insulation companies, but you can also use guidelines from the Energy Saving Trust eg that loft insulation should now be 300mm thick. More expensive improvements like better double glazing may or may not be an economic choice (in terms of payback time) and so that is a more specialised decision than the loft insulation. You are right that the specialist expertise is greatly needed, but not all house types are easy to improve.
Great advice here, and presented well. We need more of this sort of stuff. The only thought I would like to add for any Ecodan owners (and others) is that I think 'Room Target' , (with no outside sensing) can be better than weather comp option, for many situations. In simple terms, this tries to achieve the desired room temp with the lowest flow temperure. I have always like weather comp, but old 'heavy' buildings behave differently to light ones, so it can be tricky to set right.
Hi John. We just got an ecodan and am deciding if to use weather compensation or room target. Can you elaborate as to why specifically the ecodan might preform better? We have done a deep retrofit (approx 80% new build), very highly insualted, airtight and quite high thermal mass, with underfloor heating.
@@giollaliddy5817 With simple weather compensation, the heated water temperature setting rises as it gets cold outside, so if there is a sharp frost for example, then the heat pump can tend to 'rev-up'. Arguably, you might want it to 'throttle off' when the air is so cold because the COP is worse. For an old solid weighty building it may easily 'ride' the cold snap. In the case of Ecodan (and some others) there is to my knowledge no option for different day and a night compensation setting. Of course, you might have a cheap night tariff, so the night 'rev up' might be welcome so cheaper heat can be stored in the fabric of the building.. so it depends on the building (heavy or lightweight). The room target control simply looks at the room temperure, and tries to find the lowest flow temperure to satisfy room temperature. Ecodan allow varied target room temperatures over the 24hrs, so this avoids night rev-ups if you don't want them. This control will only work if there is one main area where the reference temperure can be taken, but arguably, the inside is better place to measure. Both highly insulated passive house and solid wall old buildings are 'shielded' from the outside, so weather comp is not always easy to set up. Heat Geek have experience of some of then better advanced controls, which should give good performance in all situations. Back to your Ecodan, I have personally always favoured the room target method if its possible.
@@johncantor4056 thanks for the in depth response. Are you sure ecodan allows for varying room temps during the 24 hrs? I can't seem to find this, which is why I went researching the weather comp. Perhaps it needs a 3rd party controller for this?
@@giollaliddy5817 I think there is a schedule, and you can set either on/off, or actual room temperatures over the day. You probably need the main controller configured for 'room target' in order to see this option.
@@johncantor4056 Hi. Do you need a Mitsubishi wireless controller installed in a reference room for this to work? I have individual thermostats in each room that are part of the floor heating system, so they control the circuit valves in the floor heating distributors, but are not able to send any temperature information back to the Ecodan heat pump.
Brilliant. Thank you. I'll search through your videos on the Vaillant Expanded WC now. I think that could be the next stage for us. Running at a SCOP of 3.7 for combined DHW and UF heating.
I have to set my curve at about 1.1 in the winter for required temp, but that doesn't do enough when the temp out side is about 14/15 in the spring and autumn, then I need a higher curve of about 1.5-1.7 to get the rads affecting the temp enough to heat the house up to 20. Something ain't quite right with our set up but we fudge it
Is there any chance you could consider making future videos without the background music? I'm not sure why you use it, but I personally don't think it adds anything, and I find it really distracting - especially when the volume auto-increases between your sentences. Otherwise, this is a great series. Thanks!
I agree with Nick. It’s very distracting having the music blast in during every pause in you speaking. Just set the bed music level during the video and fade up at beginning and end.
Does the same theory apply to my Vaillant Ecotec Plus gas boiler? It has all the necessary controls. Also, if you have multiple zones do you balance them all at once? I can set the curve for each zone! Thanks for taking the time to read and respond to all the messages on here!
Really helpful video for a new customer in the air source heat pump market. We will definitely be looking for a Heat Geek backed installation having watched your videos but I have a technical question: in a well-insulated house (EPC - B) with a lot of glass and passive solar gain, what is the best way for the engineer to make use of weather compensation to take into account the additional passive solar gain in some, but not all, rooms ? I’m assuming, in part, the answer will be about the location of sensors that communicate with the heat pump. I’m hoping this does not mean the heat pump has to be located in the place of greatest solar gain - the front of the property is south facing (for aesthetic reasons).
The heat pump could be anywhere. It uses air not solar! The air is the same all around your house. The first question is too broad I'm afraid. If you have underfloor heating you'll have some self regulation effect
Great video as usual. I don't (yet) have a heat pump, waiting for some retrofit work to be carried out before I seriously look at that. I have a total of ten temp sensors feeding into Home Assistant -> influx, so still at data gathering stage. But have been running Viessman gas boiler at 50 flow temp for a couple of months now, have set all TRVs to max, and increased overnight temp from 15 to 17, but only since it's got warmer. I haven't tried adjusting radiators. The house is on the whole as comfortable as it was before I turned flow temp down from 60 to 50 - which is to say when we had a few cold and windy days last month(?) the living room failed to reach target temperature all day, but is pretty much ok on cold still days. I can clearly see where radiators are too big and too small (or set up incorrectly). I've checked that my Vitodens W110 is wired to allow OpenTherm communication, but I don't have weather compensation installed. I use Hive to schedule heating and I'm monitoring Hive boiler on/off data in Home Assistant as well. I also know Hive doesn't talk OpenTherm. My question is : if I get weather compensation, will it work with Hive or will Hive cancel out the weather compensation? I asked the gas engineer who serviced the boiler and he didn't seem to know although he was willing to install a weather compensation unit.
We are still on gas (rented) but I have done everything I can to make it efficient. I would love to hear your thoughts on my setup. We don't however use weather compensation as it's and open loop modifier and requires fettling and likely to never get it right. We have a veisman boiler which supports opentherm. Which means I can control the rad circuit temp. Wax TRV suck. Being on the radiator they do not measure (and thus control) room temperature they measure the temperature of the rad. What I have is, In each room I measure the temperature of the air on the opposite wall to where the radiator is. I also measure the temperature of the radiator. I then have underfloor heating actuators on the rad. The whole sense and control is done on a raspberry pi. It looks at the room temperature and uses a PID loop to decide what the radiator temperature needs to be. This set point is used for 2 things, as an input to a 2nd PID loop that controls the actuator on the radiator to control rad temp directly and 2nd to set the flow temperature of the boiler. The system takes all rad set points from all radiators in the house and picks the highest one for the flow temp. What this means is that one of the actuators will be on with the flow temp at exactly what that radiator needs to keep the room warm with the other rads being controls downwards. Overnight the room set points in all rooms drops, then slowly ramps up to the morning when we get up. The angle of this ramp is set fairly shallow so the boiler isn't running flat out to bring the room temps up. The colder it is outside the more the room temp drops so the boiler effectively cuts in earlier. We also have presence awareness so the system knows when we are out and drops the set points and attempts to predict when we will be back and ramps the set points up in a similar way to the day/night does. This system controls the room temp to well under 0.5c often better than 0.1c depending how much the squishy humans open doors! It's running on a raspberry pi running node-red. Boiler controlled with an Arduino mini with an opentherm adapter and graphing done using graphana. The initial setup and tuning of the PID loops took a while to get right. But now it loops after itself. Only thing I do is drop the set points at the end of the spring to stop it heating for an hour on cooler mornings
You've done all that and you don't think you can install a dimple weather compensator???? Lololol The funny thing is, if you uninstall all of that and put in a 40 quid weather sensor I think your gas bill would be the same!
@@HeatGeek I wrote all that before finishing the video, zoning is actually minimal, ours is more about the fact the radiator sizing is incorrect and a loft bedroom is poorly insulated so needs a heat at times when the rest of the house is warm. The temperatures are the same just the quantity of heat those rooms require is different.
Good information and well discussed. I did find it irritating that the camera angle and range is always changing. I know this is done to keep the brain involved but it just gave me a headache...same with music.
Another great video. Am a huge fan. Do you have a physics degree? I do, and the way you approach the physics and the way you handle more subtle concepts (like the not turning off of the rads in less important rooms) is very familiar. If you don't have one, I'd suggest you consider it, not for vocational purposes, just because I think you would enjoy it. One one small point, and not a disagreement, but rather to add a (possible in rare circumstances) caveat: you describe (accurately) the importance of heating as many of the in-envelope rooms as possible, thus increasing emitter output and hence lowering the CH temp needed to get the total power required. And I agree with this... except for if you have a strange house! I do have a strange house and we do have a region which is poorly insulated (drafty as hell) and which we don't use in the winter. While it is 'inside' the house, we are able to block it off reasonably well, with very well sealed doors and curtains and so on. We do have enough emitters in the rest of the property to keep the central heating temp pretty low and still maintain the temp well. So anyway, I would have started with "it depends" but I think that would be misleading - I suspect your point stands in at least 90% of scenarios, so perhaps "it depends a little bit in rare occasions, maybe...". Hope that makes sense. I could go into far more detail, and I did do some very tedious calcs and really don't want to get into in-depth maths discussions (for which youtube is just the worst!) but they tipped the scales just in my circumstance, to turn off the rads in "the cold wing" of the house. It did assume I had very little leakage from the main bulk of the house into that region and I think I have achieved that. Anyway, love the channel, I use the points you make regularly with visitors who just LOVE to bemoan my heatpump when they see it, this especially includes a couple of old plumbers I know (children's friend's parents), who absolutely enjoy heat pump bashing for some reason!
Weather compensation system works terrible in my air conditioning system. It completely ignores the thermal mass and isolation properties of the building. Sometimes it is comfortably chilly outside around 15 degrees, but inside it is still hot at around 25 due to the sun warming all the walls all day and the AC will just work as a fan because it thinks that the heat will radiate instead of doing what I am asking that is to remove as much heat as possible from inside the building.
I was surprised you don’t touch on Opentherm. My boiler manufacturer (Ideal, S15 Vogue) advised that Opentherm is better than Weather Compensation. I run an Evohome with UFH and boiler efficiency’s currently at 89% and increasing. I also have 2 x “air to air system” that I run spring and autumn, and obviously cooling in the summer when required
Thank you for a really clear explanation. As someone who currently has a 10 year old condensing gas boiler, would the steps you suggest still be worth implementing, as I thought that the efficiency of the boiler drops off if it isn't on the eco setting?
@@forestblackberry7046 Logic plus do have weather compensation but it is quite basic, they may also have opentherm which could increase efficiency a bit although the modulation isn't the best.
There's a lot of articles debunking the myth that you should turn off your heating rather than keeping it on low when you're not in the house. It sounds like for heat pumps this doesn't exactly ring true, assuming your not out of the house for days at a time. I'd assume if you are at work on a chilly winter's day you would want to be falling back to your set back temperature rather than having your heating completely off for those hours?
@@HeatGeek Look forward to both it and, due to this video, the commissioning process coming up after my install in a couple of weeks. Might get myself one of those Govee things, surprisingly cheap.
125 square meter floor plan.EPC score D what size heat pump ball park guess.How is a punter supposed to know if the installers fitted the wrong size pump when they can’t get a simple answer.If you can help great thank you, great channel like it
That's about 1345 square foot so for heating I'd say a 4 Ton heatpump (basing that off 35btu per square ft) How well sealed and insulated your house is and what kind of temps you see in winter in your area will change that though.
VERY informative videos, thank you for taking the time to present. I have a Daikin ASHP and I also have Fan Coil Units. You focus on Rads in your video but do you have any recommendations for settings for FCUs, am I right in thinking they will be different needs than Rads? I am specifically looking to find the LWT for achieving room temps of 21 degC in the daytime. Thank you in advance
After setting weather comp, you still need to use a house thermostat because the house loses much more heat in a strong freezing wind compared to a still freezing night. If you measure the kW hrs used turning the ASHP off at night, it is considerably less than running it 24 hrs per day even with set back.
i divert the return water from my rads to a coil in a cylinder containing cold domestic water ,This preheated water is feed to the indirect tank cold taping. .Result indirect is feed with warm water and the boiler return water is at a lower temperature thus fuel savings,
Am i correct in saying that everytime the system switches to hot water mode, the weather compensation program is interrupted and the supply temperature goes back up to 50C.
With weather comp, do you have to buy the sensor that goes outside separately or does it usually come with the boiler? Looking at a bosch 8000. Also, do they need to be hard wired to the boiler itself? Thanks for all the helpful info. 👍
Seems many houses in UK has bad insulation and non low temperature heating systems. LWT 40-50 when -5 - -10 outside OMG. My LWT is 36 when outside temperature is -25 :D And even this result can be improved.
Shouldnt be the flow temperature being adjusted to inside temperature than outside? In particular, to the room with the weakest radiator (that needs the highest temperature to get the required heating power)?
Hi...Briliant Video.....just one question regarding initial preperation for setting the WC......when we put all the TRV's on Maximum should we also open up all the lockshield valves as well??
Awesome video, thank you! How long would it take to max all your internal controls, turn the heat pump on and set the compensation curve? A few hours? How long does it take a house to reach equilibrium before you can decide to tweak the curve?
Great video again. I have a Vailliant Arotherm 7kw, UFH in new build extension (150mm insulation and screed), and oversized triple columns rads in the older part of the house (all single storey bungalow) without TRVs, all set to maximum. Existing floors insulated with 100mm mineral wool, cavities filled, and 200mm loft insulation. I am struggling to get a COP of above 2.7 looking at the controls. Currently have a single zone, with one thermostat set at 17 degrees, and 16 degrees overnight. Thanks to your videos i realized the installers set my hot water tank to 55 degrees... Ive now lowered this to 46-48 degrees (but still have the weekly legionella cycle left on). Weather compensation was set at 0.9, so have reduced slightly to 0.8. This video (correct me if i misunderstood) suggests raising the thermostat 1 degree (so in my case 18degrees), but then reducing weather compensation down so it only reaches 17 degrees? will this not just keep the heat pump on constantly, as the thermostat is calling for heat continuously?
On for longer but at a lower output and higher efficiency.. your curve should be around 0.4 I recon.. maybe .5 or 0 6.. do 0.4 first. Also I found jave a buffer or llh it may be unbalanced but that needs a heat geek not homeowner
@@HeatGeek compensation curve down to 0.6 has made a big difference. COP of over 3.5 now. Minimum flow temp is set at 28 and maximum 45. Are you saying this should be different? I’ve paid for a service on this system last year, so will expect the same firm to come and sort the settings (so long as they know what they are doing). Do heat geeks offer the yearly RHI compliant service?
What a brilliant informative video I didn't even know that ashp and some boilers had heating curves unfortunately our options are oil or electric heating as we are off the grid i think that all system condensing boilers should have heating curves
But this guidance doesn't take any note of the use of the building? I am away several days a week, and don't need any heating. I really only need to heat the house of the weekend? With a heat pump I will have to pay to the heat the house when its empty??
@@HeatGeek for me I am ok at sat 20-21 for the Mrs I think she needs the house on fire haha But if I said heat geek said this then she will have to listen 😎
@@HeatGeek also just on the back of that i put heating on at 6:30AM to reach 20 but it's not even on 18 yet any reason why it may be slow in warming up or just because it's a older house and open plan? :) - thanks for the response
Any of your videos cover heating controls? Particularly when it comes to controlling lots of different systems together. Are there any master controllers out there to smartly select which is the best heat source to select at any one time, for example, on a time of use electricity tariff, and gas, which is cheaper/cleaner at any one time? Is there a controller that can work this stuff out and fully optimise? Maybe even learn and evolve it's algorithms as it goes along?
Having watched the video I am a bit confused about the target temperature when re-installing the system. The instructions are to put the thermostat and the TRVs to maximum and then adjust the compensation until the target temperature is reached. Where is the system getting the target temperature from.
Thank you so much for your efforts! I have one question regarding the ambiSENSE smart thermostatic radiator valve. What are the best settings for it to work properly? paired with an Ecovit 255 and VRC700? 1. Should I set Adaptive heat curve? 2. ‘Room temp. Mod. should be set to ‘None’ or ‘Temp. Mod.’ 3. It is absolutely important to have a VR71 to make work properly the VRC700? 4. I don't have any three-way valve - is it bad for the circuit? After HW is ready all radiators get suddenly ultra-hot. The circuit consists of the Ecovit with one zone and VIHR 150. What should I do to stop this effect? The Vaillant instructions are so unclear and no installer knows here hot Ambisense nor VRC700 works. Thank you in advance!
@@HeatGeek Thank you! When you will install or see some ambiSense smart thermostatic radiator valve it will be very useful to read how to customize the VRC700 with them. Once again thank you!
This is unbelievably helpful and have shared with other friends with ASHPs. Thank you! Am looking for some advice on our system. All help appreciated.... We have UFH downstairs and Rads upstairs. We have two heating circuits on our Stiebel Eltron WPC10 GSHP but have been advised to run both circuits on the same heat curve because “the rads will come on with the ufh” and “the system only delivers one heating flow and return output feeding both rads & ufh so not practical to have 2 different heat curves”. I feel like we maybe losing the potential efficiency gains of having ufh running at a lower heat curve because we have rads that need a higher curve. Why have two circuits but only one output? Also, there has been mention of a ‘blending valve’ so that the ufh never goes over a particular temp - is this potentially reducing efficiency gains also? I’m in the process of ‘dialling in’ our lowest heat curve over a series of days and feel like I’m getting close, but would like to be able to drop the curve for the ufh. Thanks again for the fantastic content Heat Geek!
@@HeatGeek this seems a real shame and a poor design no? Why would a GSHP have two heating circuits with independent heat curves etc but only a single output that meant the highest flow temp needed had to be met for both?
The principle of equilibrium between heat in and heat out, to minimise cycling on a heat pump -> does this same logic apply to a condensing gas boiler? Some gas boilers can modulate right down with smart thermostats -> should those with these units follow the same advice and modulate the boiler right down to keep it on all day at low flow temp?
Is there any rule of thumb about how much extra electricity is needed for the increased water flow needed for lower flow temperatures? If lowering the flow temperature of a gas boiler to a level where efficiency and comfort are ideal causes water in your radiators to flow constantly through the night (and perhaps all day as well in winters), I'm thinking that would cause some increase in electricity consumption - likely to be lower than the saving in gas consumption, but still would be good to know how to estimate this.
@@HeatGeek Thanks, and is there any way to measure and confirm this? Are there any manufacturers that state on average how much power their gas boilers use to push a litre of water for example?
@@HeatGeek I was wondering this. So my gas boiler uses 150watts when turned on. I was able to measure this quite consistently with a meter measuring the whole house. This would be 600 kwh of usage if i left the boiler on for 6 months of the year. But because i pay roughly 3 times the rate for an electricity kwh vs a gas kwh unit we're talking 1800 kwh (600 *3). On average I use 6300 kwh of gas a year in my house if I use my thermostats set to 20.5 degrees from oct to march (turning boiler on and off). I could enable opentherm with a heating curve but is it really worth it. Does your video take into account the electricity being used by the boiler. On another note, this is a great youtube channel and have learned loads (or more how little i knew about heating) from your videos. thanks
@Brian Healy it's worth it trust me. And electricity is 3x more. But gas is only say 90% efficient.. so its only 2.7 times more. And heat pumps are 350 to 450 efficient Gas boiler electric are tiny. Many thanks
I have read somewhere that for every 3degrees F. That you lower the heating water there is a 1% fuel savings , does this work with a heat pump air towater.
Having watched all your videos over the last few weeks I think I understand how each individual aspect works, such as weather compensation, modulation, achieving better condensing. But I'm struggling to understand how it all fits together into an ideal package. So how does having a weather compensating boiler fit with having Smart TRVs or UFH. If you have a weather compensating boiler like a Veissman 200 do you even need the Smart TRVs?
Great video, on the VRC700 when room temp mod is set to none will the controller take into consideration the set back temp of 18 I have chosen overnight or will it continue to heat the house to 20 which the current curve does in day time
Great video, for a Passivhaus with UFH, where the heat pump is going to be oversized, what would you do? Size the emitter as big as possible anyway to still run the HP at as low flow temp as possible and use the floor like one big buffer / storage heater, charging the extra thick 150mm slab once or twice a day? Would that still avoid short cycling and work with weather comp?
Is it possible to use weather compensation with 2 zones upstairs and downstairs controlled by a hive? Most evenings I use a wood burner downstairs, would this confuse the system? I have a Daikin 3 H HT with buffer and have had quite a few issues.
Just a question about weather compensation.. What happens if you were to go on holiday and want to turn off the central heating (empty house)... When you get back the house will be cold and you will switch the CH on.. With weather compensation it'll only lazily warm up rather than quickly attaining a setpoint (as the radiators won't be that hot). Is there any way around this? Other than modulating using load compensation... Or do some boilers have a weather compensation bypass for this scenario.
You would only set it to reduced target temperature. In the last 10 years I've not really had this problem.. radiator output will also be increased at the air to water dt is increased.. and there's holiday timers on decent controls to set it to warm for the day your back..
Great advice on the weather compensation but I think your advice on hot water storage temps might get a bit of backlash. Especially for elderly people who don’t use much hot water. Keeping your cylinder temperature lower than 50 degrees for a sustained period is not a sensible idea at all.
Hello, Thank You so much for an in depth explanation ; I have a Midea M thermal heat pump that has option on the wired controller between desired water flow temp and desired room temp - does that have anything to do with the weather compensation - meaning if i set the desired water flow temperature the pump will always try to hit that value ? Thank You for your help !
What's missing is 1 pick opentherm boiler AND opentherm controls 2 install a weather compensator 3 Size your boiler not some lazy oversized choice by installers 4 If it's a replacement boiler , power flush the rads as part of the install quote.Either a hose appears or a power flush pump. 5 Home gets cold very quickly then invest in some insulation.Attics are the obvious choice but crap exterior doors, the PVC double glazing windows are not designed to be maintenance free for decades, cavity wall insulation is a no brainer and hidden benefit.
Can that viesmann boiler still condensate at 85 degrees when the outside temperatures are -30 although I doubt this would happen in the uk also I can't understand why all gas and oil condensing system boilers don't have this energy saving devise as it surety it wouldn't take much knowledge to replace the potentiometer with a circuit board with different resistances linked to an outside sensor
What you are envisaging is load compensation ie an automatic reduction in boiler temperature when the rooms are getting up to temperature. It's similar in principle to weather compensation but is responding to indoor temperature rather than outdoor. Very worthwhile. I believe Veissman boilers can offer load compensation.
I am currently having a strange situation. The Vaillant air to water heatpump flow temperature didn't increase to the targeted temperature( 41 C targeted vs 37 C on the flow to radiator). Seems this is causing the heatpump part of flow temperature gets very high to near 60 degrees C. The electricity consumption also increased by a factor of 3 when this happened. Any idea how to optimize it? Or it could be a problem with the system?
I’m currently testing my heat pump system for the correct heat curve. Bad installation (long story) and I have to set the temperature sensor to water only. The main controller is in a bad location as it’s in a Utility room with a clothes dryer so using the air sensor is not an option. Would you advise moving the controller so to avail of the air sensor also? No matter what heat curve set points I choose, the unit is spitting out heat and house is too warm!!
I was wondering, are there optimal radiator designs for flow rate? Ie does a two column radiator flow better than a four column rad? or is there some other design altogether?
Very well explained, however I’m an Architect! I fear this will be too much when trying to explain to clients. In saying that, the installer should ask three or four questions prior to set up, to take all this out of the clients mind! Very much appreciate the video tho! 👍👍👍
Not just you. Everybody wants life to be as simple and hands-off as possible. However it's also important to save on energy bills as much as possible and that's what efficiency (COP) is all about. But this is not really aimed at the user, it's really explaining what the installer should do, ideally. And if the installer does all of this and gets it right then the user doesn't need to change much, ever.
Condensing boiler without weather compensation here. My understanding was that for maximum efficiency, my flow temp should be 57 degrees apx. Will going lower bring more efficiency?
Yes, there is no magic temperature, whoever said 57deg. Your boiler efficiency increases as you lower the flow temp; mine is often reduced to 33deg at this time of the year. But it can't heat the house from cold at that temp, or at least it can't heat the house from cold quickly.
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I am looking at heat pumps but i live in a BISF house that has been externally insulated early 2005 the question is it worth me looking at this form of heating alternitive to gas
Thanks for the video but please no background music or if you do don't make it dynamic to your voice where it gets louder when you don't speak.
Had to quit the video. Bad!
As Adam would say " A simple trick but massive results."
Great video again. Background music edited in a strange way, getting louder in speech breaks. (Usually use -28 - 30db throughout)
Thank you so much. Your short video summarised everything I have learned over the last 2 years since my heat pump was installed. You have clearly explained everything I have been doing wrong, and why my SCOP is only 2.2. I might even ask my wife to watch the video!
Thank you so much for this video. Just turned my weather compensation on after it being set to a flat 40 flow temp by the installers 4 years ago. I didn't dare touch it until watching this. Hopefully the on/off cycling will cut down considerably.
I have a very low cost 1.30am to 6.30am tariff so actually 'charge' up my floor slab during these hours which normally means the heat pump doesn't kick back in until about 2pm when it's cold outside. It seems to work well solar and home battery usually meaning I don't have to use any high rate electric at all. Might not be the most efficient but it's definitely the cheapest and also gives me a lovely warm floor first thing in the morning :)
I've been nearly years with ours set to a fixed temp 😆.
Very good explanation which confirms what some others have been telling me. Did a test of WC and then constant 45c flow temp but only over a couple of days and no diff on energy consumed or cop but need to check over a longer period, especially as temps always diff. Please, please, please drop the music background though, it is very distracting when trying to concentrate. Thanks!
Seconded. We're already on our computers; we can play music whenever we like… ✌😜💜
Agree about the irrelevant and distracting music.
Great video. Because of the info found here and other Heat Geek videos I fined tuned my system, quit zoning, no setback temps.
My setup is Vaillant turbotec plus combi boiler, 12 year old, 28 KW (non condensing), 8 rads (3 - 1200x400; 4 - 1400x600; 1 -1600x600), 22 type +1 towel rail, in a single series loop, controlled by Tado thermostat with all functions active, connected and configured for ebus protocol.
I`ve got a detached 70`s old brick build, 125 m2, thick walls, 450-500mm, concrete floors covered with timber board, both uninsulated; loft has 200mm mineral wool insulation, except a room; double glazing doors and windows.
I heat 24/7 at 22,7 C, no setback temp, no zoning, all TRV`s are fully open. I consumed 18 mc3/day, 10 EUR/8.6 GBP (10.01.), with an average outside temp of -3C throughout the full day.
Tado modulates the flow of the boiler at somewhat low temperatures 42-52C, for the example above, (the boiler does cycle) and when it`s slightly warmer (0 to 5 C outside) between 38 -46C flow; on a sunny day 36-44C flow.
Considering this operation mode do you think I could switch to a condensing boiler or save it for a major renovation I am planning in 2-3 years’ time (full insulation, underfloor heating, may be a heat pump)?
Thank you and i hope you extend your heat geeks network outside UK, in the future. Love your work.
Greetings from Romania
I had homeserve fit my Worcester 4000 the fitters left the boiler in the highest settings thank god for heat geek thank you now I have cheaper bills and a warmer home 👍
Good vid, very well explained... “3rd party control strangling the heat pump” - love that!
Really useful - I now understand all the graphs for my Worcester CDI system boiler & Wave / EasyControl Weather Compensation 👍
Wow! Thank you so much for your informative videos. I wish i had seen them a year ago. I had a heat pump installed in June, along with wall insulation, new radiators and solar panels. This was all under the ECO4 scheme, and when the company first came he said that an ASHP would definitely save me money. I live in rural Scotland and was using oiul for heating. The work took two months to complete, and afterwards the house was very comfortable. In September my electric bill rose to £139, which was bearable, but in October it rose to £283! Now I am really worried that the colder months will cost a lot more, and this indicates that the new system will not be saving me money after all. Having watched this video and checked some settings, I now know that the ASHP is not set to weather compensation and they have also given me two zones, each with an external thermostat. I have thermometers in each downstairs room, and the temperatures recorded are not good, with one room as low as 12 degrees, even though the zone thermostat is set to 17 degrees. None of the rooms are recording 17 degrees (15 degrees is the highest). The thermostats do change at different times of the day, and I now believe this could be an important issue, so I plan to change the unit to weather compensation and change the thermoststs to a static temperature all day. I hope this will make us more comfortable and reduce the costs. If not, I will be forced to look at other solutions, as I am a pensioner and cannot afford extremely large electric bills. Maybe I should have only got the solar panels and insulation. Maybe my oil bills and my electric bills will have both reduced.
Thank you very much for providing this information. I recently moved into a new home with GSHP and had no idea how to utilise it effectively. With this knowledge, I intend to operate a more efficient system. One thing I don't understand is the degree minute setting. Currently, it is set to -60DM. Every 60 minutes, the compressor appears to cycle off and on. The compressor appears to heat up more than the projected flow temperature.
Current configurations
Current Value 100DM
Start Compressor -60DM
diff. between additional steps 100DM
Background music on auto gain is a no no, so distracting. Information is great and on point, spoilt by background music. It's really not needed unless you are in a lift.
🤣👍 you'll get used to it I think 🤣 I'll ask to dial back though...
Great tips, really bad soundtrack which makes the advice lose impact. Can we have a version without the music please???
@@nealmurphy74 it's difficult.. young people keep telling us to leave it in and older to take out.. we're kind of caught in the middle 😳
@@HeatGeek Damn I must be an older person! I don't mind background music if it doesn't intrude, but you can hold a stage with your content without needing gimmicks. Thanks for producing the video.
@@nealmurphy74 lol sorry mate. I don't disagree.. its a point of contention for sure!!!
I have an Ecodan system that works fairly well (except Mitsubishi think that it is OK for it to totally ice up for 20 minutes before a 2 minutes defrost cycle) and is reporting a SCOP of 5.0 in a very old house.
My cunning plan varied the compensation curve every two weeks, plotting the amount of time the system ran against daily average outside temp. I kept dropping the curve until the system ran between 80 and 95 percent of the time.
I have trialled fitting low speed computer fans under the two or three layer rads to compensate for the lack of convection at low temps and this has worked very well, with the particular rad turning off more often. These use about 5W total for a 1.5m triple layer rad, and are controlled by a cheap programmable temperature sensor, and I reckon that I will be able to drop the temp by about 2 degrees when I roll them out through the house. A commercial system reports 20% higher output with fans, but those were expensive, and the small high speed fans made the fins in the rads sing.
I am also trying polycarbonate secondary glazing to reduce heat loss, and also allow lower delivery temps, with our 200 year old windows.
Not that I am obsessed of course.
Amazing!
@@HeatGeekis this sort of 80-95% run time what we are aiming for?
I have SCOP envy!
Blooming great information as usual, and lovely to hear the talk about removing setback as much as possible. Would love to spend some time with you on understanding zoning. Our advice to customer is that zoning (when done correctly) allows for the comfort in each room to be controlled, i.e. your bedrooms can be controlled lower than living areas, under the number 1 rule of continual operating conditions. (mainly talking UFH but does apply to rad's as well). This can also help protect against solar gain a little in south-facing areas. But if removing demand affects the COP, we want to make sure the advice is spot on and harmonious with the rest of the industry.
P.s. look for a heat geek on the map.. they'll advise
I'd say the purist answer is firstly to try and balance room heat losses & gains using additional insulation and window shading, based on calculations. But as the vid explains in all cases make sure all emitters (underfloor or radiators) are sufficiently sized and correctly balanced to each room load. Then the house should heat fairly evenly without falling back on zone controls. If room losses/gains have large differences and emitters are not balanced you generally end up with the highest loss zone over-driving the the whole system which wastes energy.
Fantastic video. I appreciated the idea of lower flow temperature for your ASHP equals better efficiency. But I hadn’t understood the logic behind it - balancing heat demand to heat loss whilst keeping your room at a comfortable temperature. Brilliant explanation. I will be sharing the video and testing the logic with my ASHP. Thank you
Thanks!!
I really appreciate your videos man ! Tones of important knowledge!
8 degrees outside today.Temp set to 23 degrees.Flow temp is 16 degrees.Vaillant system.
Great and clear video! How I wished to have such simple system :) When you add two floors, wooden flooring(limit temp to 40C max), undergrounf water heating and Nest control of one zone, do not know what degree is needed to balance the system ..
Surely one's energy bills have the info needed to calculate a house's insulation performance. I use them to work out how much energy our house uses across the year. Mine needs improving before I can consider a heat pump as an alternative to gas boiler. What I will need is to know how to work out the best way to improve it. In my opinion, this specialist expertise is what will be most needed before 2030. The right answers for my house are not obvious.
No because it could be a really poorly installed system.. crap cylinder.. High gas cooking.. also does not shown the relative size of rads. Its needs a survey.
@Heat Geek OK about some aspects of poor installation, such as a heating system that doesn't provide enough heat when on all of the time. Fitting a heat pump that cannot output enough heat to an inadequately insulated house creates that problem as you have said elsewhere.
OK about boilers that shove heat up the chimney too.
Being indoors or within one's living space, poor quality cylinders probably give out their wild heat to a nearby room (where the heat is not used to heat water).
I should add a caveat around households that cannot afford to heat the home to a comfortable level all of the time. The true heating requirements would be understated in bills.
Add an adjustment or a caveat about houses that are not occupied all of the time covered by the energy invoices.
Yes of course, the higher the energy consumption on the bills the more important it is to improve energy efficiency of the building and thus have the comfort without wasting money. The choices and specification of these insulation improvements is best done by specialist insulation companies, but you can also use guidelines from the Energy Saving Trust eg that loft insulation should now be 300mm thick. More expensive improvements like better double glazing may or may not be an economic choice (in terms of payback time) and so that is a more specialised decision than the loft insulation. You are right that the specialist expertise is greatly needed, but not all house types are easy to improve.
Very annoying background music at the start.
Totally worth it though, because the information in the video is amazingly good! 👍
I have used an outdoor reset control on my five builds , and they work quite well , except when the wind comes up.
Excellent video - our ASHP is going in next week and now I know how to go about setting the temperatures etc! Superb stuff, thanks.
Your installer should be doing this not you
@@HeatGeek I'm sure they will. I'm a tech geek though so I like to understand what they're doing and why they're doing it :)
Great advice here, and presented well. We need more of this sort of stuff. The only thought I would like to add for any Ecodan owners (and others) is that I think 'Room Target' , (with no outside sensing) can be better than weather comp option, for many situations. In simple terms, this tries to achieve the desired room temp with the lowest flow temperure. I have always like weather comp, but old 'heavy' buildings behave differently to light ones, so it can be tricky to set right.
Hi John. We just got an ecodan and am deciding if to use weather compensation or room target. Can you elaborate as to why specifically the ecodan might preform better? We have done a deep retrofit (approx 80% new build), very highly insualted, airtight and quite high thermal mass, with underfloor heating.
@@giollaliddy5817 With simple weather compensation, the heated water temperature setting rises as it gets cold outside, so if there is a sharp frost for example, then the heat pump can tend to 'rev-up'. Arguably, you might want it to 'throttle off' when the air is so cold because the COP is worse. For an old solid weighty building it may easily 'ride' the cold snap. In the case of Ecodan (and some others) there is to my knowledge no option for different day and a night compensation setting. Of course, you might have a cheap night tariff, so the night 'rev up' might be welcome so cheaper heat can be stored in the fabric of the building.. so it depends on the building (heavy or lightweight). The room target control simply looks at the room temperure, and tries to find the lowest flow temperure to satisfy room temperature. Ecodan allow varied target room temperatures over the 24hrs, so this avoids night rev-ups if you don't want them. This control will only work if there is one main area where the reference temperure can be taken, but arguably, the inside is better place to measure. Both highly insulated passive house and solid wall old buildings are 'shielded' from the outside, so weather comp is not always easy to set up. Heat Geek have experience of some of then better advanced controls, which should give good performance in all situations. Back to your Ecodan, I have personally always favoured the room target method if its possible.
@@johncantor4056 thanks for the in depth response. Are you sure ecodan allows for varying room temps during the 24 hrs? I can't seem to find this, which is why I went researching the weather comp. Perhaps it needs a 3rd party controller for this?
@@giollaliddy5817 I think there is a schedule, and you can set either on/off, or actual room temperatures over the day. You probably need the main controller configured for 'room target' in order to see this option.
@@johncantor4056 Hi. Do you need a Mitsubishi wireless controller installed in a reference room for this to work? I have individual thermostats in each room that are part of the floor heating system, so they control the circuit valves in the floor heating distributors, but are not able to send any temperature information back to the Ecodan heat pump.
All very important! Daikin use weather comp, if you use our room thermostat it combines this with room comp and you can even have water comp....
Brilliant. Thank you. I'll search through your videos on the Vaillant Expanded WC now. I think that could be the next stage for us.
Running at a SCOP of 3.7 for combined DHW and UF heating.
Great vid. Well explained, looking forward to some colder weather (?) To try adjusting the heat curve...
I have to set my curve at about 1.1 in the winter for required temp, but that doesn't do enough when the temp out side is about 14/15 in the spring and autumn, then I need a higher curve of about 1.5-1.7 to get the rads affecting the temp enough to heat the house up to 20. Something ain't quite right with our set up but we fudge it
Is there any chance you could consider making future videos without the background music? I'm not sure why you use it, but I personally don't think it adds anything, and I find it really distracting - especially when the volume auto-increases between your sentences. Otherwise, this is a great series. Thanks!
Due to our long term demographic this is likely the format. Thankyou though!!!
I agree with Nick. It’s very distracting having the music blast in during every pause in you speaking. Just set the bed music level during the video and fade up at beginning and end.
Does the same theory apply to my Vaillant Ecotec Plus gas boiler? It has all the necessary controls. Also, if you have multiple zones do you balance them all at once? I can set the curve for each zone! Thanks for taking the time to read and respond to all the messages on here!
Hi.. yes but to a lesser degree. With zoning Watch our why not to zone vid
Really helpful video for a new customer in the air source heat pump market. We will definitely be looking for a Heat Geek backed installation having watched your videos but I have a technical question: in a well-insulated house (EPC - B) with a lot of glass and passive solar gain, what is the best way for the engineer to make use of weather compensation to take into account the additional passive solar gain in some, but not all, rooms ? I’m assuming, in part, the answer will be about the location of sensors that communicate with the heat pump. I’m hoping this does not mean the heat pump has to be located in the place of greatest solar gain - the front of the property is south facing (for aesthetic reasons).
The heat pump could be anywhere. It uses air not solar! The air is the same all around your house. The first question is too broad I'm afraid. If you have underfloor heating you'll have some self regulation effect
Well done mate, great video👍👍
Great video as usual.
I don't (yet) have a heat pump, waiting for some retrofit work to be carried out before I seriously look at that. I have a total of ten temp sensors feeding into Home Assistant -> influx, so still at data gathering stage. But have been running Viessman gas boiler at 50 flow temp for a couple of months now, have set all TRVs to max, and increased overnight temp from 15 to 17, but only since it's got warmer. I haven't tried adjusting radiators.
The house is on the whole as comfortable as it was before I turned flow temp down from 60 to 50 - which is to say when we had a few cold and windy days last month(?) the living room failed to reach target temperature all day, but is pretty much ok on cold still days. I can clearly see where radiators are too big and too small (or set up incorrectly).
I've checked that my Vitodens W110 is wired to allow OpenTherm communication, but I don't have weather compensation installed.
I use Hive to schedule heating and I'm monitoring Hive boiler on/off data in Home Assistant as well. I also know Hive doesn't talk OpenTherm.
My question is : if I get weather compensation, will it work with Hive or will Hive cancel out the weather compensation? I asked the gas engineer who serviced the boiler and he didn't seem to know although he was willing to install a weather compensation unit.
Wc will still work. If you have rhe newer 100 or the 200 model get rid of that junk hive and use the intelligent wc
Brilliant clear and simple explanation. Should you set the weather compensation curve before balancing or vice versa? Thank you
Kind of simultaneously..
We are still on gas (rented) but I have done everything I can to make it efficient.
I would love to hear your thoughts on my setup.
We don't however use weather compensation as it's and open loop modifier and requires fettling and likely to never get it right.
We have a veisman boiler which supports opentherm. Which means I can control the rad circuit temp.
Wax TRV suck. Being on the radiator they do not measure (and thus control) room temperature they measure the temperature of the rad.
What I have is, In each room I measure the temperature of the air on the opposite wall to where the radiator is. I also measure the temperature of the radiator.
I then have underfloor heating actuators on the rad.
The whole sense and control is done on a raspberry pi.
It looks at the room temperature and uses a PID loop to decide what the radiator temperature needs to be.
This set point is used for 2 things, as an input to a 2nd PID loop that controls the actuator on the radiator to control rad temp directly and 2nd to set the flow temperature of the boiler.
The system takes all rad set points from all radiators in the house and picks the highest one for the flow temp.
What this means is that one of the actuators will be on with the flow temp at exactly what that radiator needs to keep the room warm with the other rads being controls downwards.
Overnight the room set points in all rooms drops, then slowly ramps up to the morning when we get up. The angle of this ramp is set fairly shallow so the boiler isn't running flat out to bring the room temps up. The colder it is outside the more the room temp drops so the boiler effectively cuts in earlier.
We also have presence awareness so the system knows when we are out and drops the set points and attempts to predict when we will be back and ramps the set points up in a similar way to the day/night does.
This system controls the room temp to well under 0.5c often better than 0.1c depending how much the squishy humans open doors!
It's running on a raspberry pi running node-red. Boiler controlled with an Arduino mini with an opentherm adapter and graphing done using graphana.
The initial setup and tuning of the PID loops took a while to get right. But now it loops after itself. Only thing I do is drop the set points at the end of the spring to stop it heating for an hour on cooler mornings
You've done all that and you don't think you can install a dimple weather compensator???? Lololol
The funny thing is, if you uninstall all of that and put in a 40 quid weather sensor I think your gas bill would be the same!
Also watch our video called 'why not to zone heating systems'
@@HeatGeek I wrote all that before finishing the video, zoning is actually minimal, ours is more about the fact the radiator sizing is incorrect and a loft bedroom is poorly insulated so needs a heat at times when the rest of the house is warm. The temperatures are the same just the quantity of heat those rooms require is different.
@@DorsetSaferRoads you cab get around that with balancing
@@HeatGeek thats effectively what my system is doing. Balancing only really works for one outside temperature too I think?
Great video and information. Struggling with the compression on the audio though
Good information and well discussed. I did find it irritating that the camera angle and range is always changing. I know this is done to keep the brain involved but it just gave me a headache...same with music.
Another great video. Am a huge fan. Do you have a physics degree? I do, and the way you approach the physics and the way you handle more subtle concepts (like the not turning off of the rads in less important rooms) is very familiar. If you don't have one, I'd suggest you consider it, not for vocational purposes, just because I think you would enjoy it.
One one small point, and not a disagreement, but rather to add a (possible in rare circumstances) caveat: you describe (accurately) the importance of heating as many of the in-envelope rooms as possible, thus increasing emitter output and hence lowering the CH temp needed to get the total power required. And I agree with this... except for if you have a strange house! I do have a strange house and we do have a region which is poorly insulated (drafty as hell) and which we don't use in the winter. While it is 'inside' the house, we are able to block it off reasonably well, with very well sealed doors and curtains and so on. We do have enough emitters in the rest of the property to keep the central heating temp pretty low and still maintain the temp well. So anyway, I would have started with "it depends" but I think that would be misleading - I suspect your point stands in at least 90% of scenarios, so perhaps "it depends a little bit in rare occasions, maybe...". Hope that makes sense. I could go into far more detail, and I did do some very tedious calcs and really don't want to get into in-depth maths discussions (for which youtube is just the worst!) but they tipped the scales just in my circumstance, to turn off the rads in "the cold wing" of the house. It did assume I had very little leakage from the main bulk of the house into that region and I think I have achieved that.
Anyway, love the channel, I use the points you make regularly with visitors who just LOVE to bemoan my heatpump when they see it, this especially includes a couple of old plumbers I know (children's friend's parents), who absolutely enjoy heat pump bashing for some reason!
Weather compensation system works terrible in my air conditioning system. It completely ignores the thermal mass and isolation properties of the building.
Sometimes it is comfortably chilly outside around 15 degrees, but inside it is still hot at around 25 due to the sun warming all the walls all day and the AC will just work as a fan because it thinks that the heat will radiate instead of doing what I am asking that is to remove as much heat as possible from inside the building.
Wow! Does this work for oil boilers (Grant) who offer a weather compensation add-on but not mentioned by the installer. 😡
I set my boiler flow for 80’c and my house can’t get passed 20.5’c.
If I try 65’c I can’t get past 19’c.
I was surprised you don’t touch on Opentherm. My boiler manufacturer (Ideal, S15 Vogue) advised that Opentherm is better than Weather Compensation. I run an Evohome with UFH and boiler efficiency’s currently at 89% and increasing. I also have 2 x “air to air system” that I run spring and autumn, and obviously cooling in the summer when required
Because heat pumps don't use open therm and open therm controls are poor. There is no decent weather compensated openthem. That's why!
Great video, well explained!
Cheers Nick! Hope your well!
Thank you for a really clear explanation. As someone who currently has a 10 year old condensing gas boiler, would the steps you suggest still be worth implementing, as I thought that the efficiency of the boiler drops off if it isn't on the eco setting?
It's unlikely tour boiler has weather compensation, which boiler is it?
@@HeatGeek It's an Ideal Logic+ Heat 24.
@@forestblackberry7046 Logic plus do have weather compensation but it is quite basic, they may also have opentherm which could increase efficiency a bit although the modulation isn't the best.
There's a lot of articles debunking the myth that you should turn off your heating rather than keeping it on low when you're not in the house. It sounds like for heat pumps this doesn't exactly ring true, assuming your not out of the house for days at a time. I'd assume if you are at work on a chilly winter's day you would want to be falling back to your set back temperature rather than having your heating completely off for those hours?
That video is due out in a couple weeks time
@@HeatGeek Look forward to both it and, due to this video, the commissioning process coming up after my install in a couple of weeks. Might get myself one of those Govee things, surprisingly cheap.
125 square meter floor plan.EPC score D what size heat pump ball park guess.How is a punter supposed to know if the installers fitted the wrong size pump when they can’t get a simple answer.If you can help great thank you, great channel like it
Watch this to answer that question
ruclips.net/video/-VJQLcU_YjU/видео.html
That's about 1345 square foot so for heating I'd say a 4 Ton heatpump (basing that off 35btu per square ft) How well sealed and insulated your house is and what kind of temps you see in winter in your area will change that though.
Great video.
Absolutely brilliant explanation. Thank you
VERY informative videos, thank you for taking the time to present.
I have a Daikin ASHP and I also have Fan Coil Units.
You focus on Rads in your video but do you have any recommendations for settings for FCUs, am I right in thinking they will be different needs than Rads?
I am specifically looking to find the LWT for achieving room temps of 21 degC in the daytime.
Thank you in advance
After setting weather comp, you still need to use a house thermostat because the house loses much more heat in a strong freezing wind compared to a still freezing night. If you measure the kW hrs used turning the ASHP off at night, it is considerably less than running it 24 hrs per day even with set back.
Both of these things are untrue
i divert the return water from my rads to a coil in a cylinder containing cold domestic water ,This preheated water is feed to the indirect tank cold taping. .Result indirect is feed with warm water and the boiler return water is at a lower temperature thus fuel savings,
Am i correct in saying that everytime the system switches to hot water mode, the weather compensation program is interrupted and the supply temperature goes back up to 50C.
Not necessarily 50c but to what ever is required for hot water yes..
With weather comp, do you have to buy the sensor that goes outside separately or does it usually come with the boiler? Looking at a bosch 8000. Also, do they need to be hard wired to the boiler itself? Thanks for all the helpful info. 👍
Seems many houses in UK has bad insulation and non low temperature heating systems.
LWT 40-50 when -5 - -10 outside OMG.
My LWT is 36 when outside temperature is -25 :D And even this result can be improved.
Great information. Found the pumping backwards background music very distracting and annoying. Cheers
Did you pay for the video?
Did someone force you to watch it?
Did you know that videos can be muted and automatic subtitles can be enabled?
Shouldnt be the flow temperature being adjusted to inside temperature than outside? In particular, to the room with the weakest radiator (that needs the highest temperature to get the required heating power)?
Brilliant!!! Thanks so much
Hi...Briliant Video.....just one question regarding initial preperation for setting the WC......when we put all the TRV's on Maximum should we also open up all the lockshield valves as well??
No
Awesome video, thank you!
How long would it take to max all your internal controls, turn the heat pump on and set the compensation curve? A few hours? How long does it take a house to reach equilibrium before you can decide to tweak the curve?
Depends on the house to be honest.. a few hours to a day or 2.
@@ChapmanPlumbing thanks Adam, not something the installer could do then? I guess they have to go off their calcs?
@@criggeruk yes something the installer should do, intermittent visits and or calls to adjust..
@@ChapmanPlumbing jb
@@ChapmanPlumbing o non mnp
Awesome how you explain these matters. Question; can I use a fi Viessmann advanced controler with a Grant oil boiler?
Thanks for another great video
Great video again. I have a Vailliant Arotherm 7kw, UFH in new build extension (150mm insulation and screed), and oversized triple columns rads in the older part of the house (all single storey bungalow) without TRVs, all set to maximum. Existing floors insulated with 100mm mineral wool, cavities filled, and 200mm loft insulation. I am struggling to get a COP of above 2.7 looking at the controls.
Currently have a single zone, with one thermostat set at 17 degrees, and 16 degrees overnight.
Thanks to your videos i realized the installers set my hot water tank to 55 degrees... Ive now lowered this to 46-48 degrees (but still have the weekly legionella cycle left on). Weather compensation was set at 0.9, so have reduced slightly to 0.8.
This video (correct me if i misunderstood) suggests raising the thermostat 1 degree (so in my case 18degrees), but then reducing weather compensation down so it only reaches 17 degrees? will this not just keep the heat pump on constantly, as the thermostat is calling for heat continuously?
On for longer but at a lower output and higher efficiency.. your curve should be around 0.4 I recon.. maybe .5 or 0 6.. do 0.4 first.
Also I found jave a buffer or llh it may be unbalanced but that needs a heat geek not homeowner
@@HeatGeek thanks. I do have a buffer tank. Will adjust the compensation curve down a bit and see if that improves things.
@@HeatGeek the controls on mine are showing a target flow temp of 0. It does have minimum at 30 and max at 45. Is this right?
@Mr Hazell no, none of that is correct. Who on earth would tell you that? Please get a heat geek in
@@HeatGeek compensation curve down to 0.6 has made a big difference. COP of over 3.5 now. Minimum flow temp is set at 28 and maximum 45. Are you saying this should be different? I’ve paid for a service on this system last year, so will expect the same firm to come and sort the settings (so long as they know what they are doing). Do heat geeks offer the yearly RHI compliant service?
Dump the background music but otherwise a very good and informative vlog :-)
What a brilliant informative video I didn't even know that ashp and some boilers had heating curves unfortunately our options are oil or electric heating as we are off the grid i think that all system condensing boilers should have heating curves
But, an ASHP is an electric form of heating? We, like many others in our village, removed our oil heating to install a much more efficient ASHP.
How does this work when the heat pump has an incorporated tank? How do you set the temperature to the tank vs room?
Very informative, great job!
Going to watch it over a few times though, lots of info! 😅
But this guidance doesn't take any note of the use of the building? I am away several days a week, and don't need any heating. I really only need to heat the house of the weekend? With a heat pump I will have to pay to the heat the house when its empty??
For the Vaillant, to run without the thermostat switching the heating off, do you set ‘Room temp. Mod.’ To ‘None’ or ‘Temp. Mod.’ ? Thanks
Either.. mod will enable the stat to internal influence (more responsive but potentially less efficient)
Question 1. What should I set my stat to if the house reaches below a certain temp what should I put?
What's the minimum while feeling comfortable?
@@HeatGeek for me I am ok at sat 20-21 for the Mrs I think she needs the house on fire haha
But if I said heat geek said this then she will have to listen 😎
@@HeatGeek also just on the back of that i put heating on at 6:30AM to reach 20 but it's not even on 18 yet any reason why it may be slow in warming up or just because it's a older house and open plan? :) - thanks for the response
Any of your videos cover heating controls?
Particularly when it comes to controlling lots of different systems together. Are there any master controllers out there to smartly select which is the best heat source to select at any one time, for example, on a time of use electricity tariff, and gas, which is cheaper/cleaner at any one time? Is there a controller that can work this stuff out and fully optimise? Maybe even learn and evolve it's algorithms as it goes along?
Having watched the video I am a bit confused about the target temperature when re-installing the system. The instructions are to put the thermostat and the TRVs to maximum and then adjust the compensation until the target temperature is reached. Where is the system getting the target temperature from.
Thank you so much for your efforts!
I have one question regarding the ambiSENSE smart thermostatic radiator valve. What are the best settings for it to work properly? paired with an Ecovit 255 and VRC700?
1. Should I set Adaptive heat curve?
2. ‘Room temp. Mod. should be set to ‘None’ or ‘Temp. Mod.’
3. It is absolutely important to have a VR71 to make work properly the VRC700?
4. I don't have any three-way valve - is it bad for the circuit? After HW is ready all radiators get suddenly ultra-hot. The circuit consists of the Ecovit with one zone and VIHR 150. What should I do to stop this effect?
The Vaillant instructions are so unclear and no installer knows here hot Ambisense nor VRC700 works.
Thank you in advance!
Look at our vailant settings video from a week or 2 ago
@@HeatGeek Thank you! When you will install or see some ambiSense smart thermostatic radiator valve it will be very useful to read how to customize the VRC700 with them. Once again thank you!
@@adrianhancu we don't advise them typically
This is unbelievably helpful and have shared with other friends with ASHPs. Thank you!
Am looking for some advice on our system. All help appreciated....
We have UFH downstairs and Rads upstairs. We have two heating circuits on our Stiebel Eltron WPC10 GSHP but have been advised to run both circuits on the same heat curve because “the rads will come on with the ufh” and “the system only delivers one heating flow and return output feeding both rads & ufh so not practical to have 2 different heat curves”.
I feel like we maybe losing the potential efficiency gains of having ufh running at a lower heat curve because we have rads that need a higher curve. Why have two circuits but only one output? Also, there has been mention of a ‘blending valve’ so that the ufh never goes over a particular temp - is this potentially reducing efficiency gains also?
I’m in the process of ‘dialling in’ our lowest heat curve over a series of days and feel like I’m getting close, but would like to be able to drop the curve for the ufh.
Thanks again for the fantastic content Heat Geek!
An electronic mixing valve gives a second flow temp. There are no efficiency gains tho. The unit always has to fire to the highest temp
@@HeatGeek this seems a real shame and a poor design no? Why would a GSHP have two heating circuits with independent heat curves etc but only a single output that meant the highest flow temp needed had to be met for both?
The principle of equilibrium between heat in and heat out, to minimise cycling on a heat pump -> does this same logic apply to a condensing gas boiler? Some gas boilers can modulate right down with smart thermostats -> should those with these units follow the same advice and modulate the boiler right down to keep it on all day at low flow temp?
Yes
Is there any rule of thumb about how much extra electricity is needed for the increased water flow needed for lower flow temperatures?
If lowering the flow temperature of a gas boiler to a level where efficiency and comfort are ideal causes water in your radiators to flow constantly through the night (and perhaps all day as well in winters), I'm thinking that would cause some increase in electricity consumption - likely to be lower than the saving in gas consumption, but still would be good to know how to estimate this.
Tiny.. like watts
@@HeatGeek Thanks, and is there any way to measure and confirm this? Are there any manufacturers that state on average how much power their gas boilers use to push a litre of water for example?
@@HeatGeek I was wondering this. So my gas boiler uses 150watts when turned on. I was able to measure this quite consistently with a meter measuring the whole house. This would be 600 kwh of usage if i left the boiler on for 6 months of the year. But because i pay roughly 3 times the rate for an electricity kwh vs a gas kwh unit we're talking 1800 kwh (600 *3). On average I use 6300 kwh of gas a year in my house if I use my thermostats set to 20.5 degrees from oct to march (turning boiler on and off). I could enable opentherm with a heating curve but is it really worth it. Does your video take into account the electricity being used by the boiler. On another note, this is a great youtube channel and have learned loads (or more how little i knew about heating) from your videos. thanks
@Brian Healy it's worth it trust me. And electricity is 3x more. But gas is only say 90% efficient.. so its only 2.7 times more.
And heat pumps are 350 to 450 efficient
Gas boiler electric are tiny.
Many thanks
I have read somewhere that for every 3degrees F. That you lower the heating water there is a 1% fuel savings , does this work with a heat pump air towater.
Do you know how Ideal combi esp1 weather compensation working?
Having watched all your videos over the last few weeks I think I understand how each individual aspect works, such as weather compensation, modulation, achieving better condensing. But I'm struggling to understand how it all fits together into an ideal package. So how does having a weather compensating boiler fit with having Smart TRVs or UFH. If you have a weather compensating boiler like a Veissman 200 do you even need the Smart TRVs?
not really no... check out the why not to zone video
ruclips.net/video/zpTVIeUh04E/видео.html
Great video, on the VRC700 when room temp mod is set to none will the controller take into consideration the set back temp of 18 I have chosen overnight or will it continue to heat the house to 20 which the current curve does in day time
Yes it will use set back!! Definitely keep none if it works!
If it takes 8 hours to reach the comfort level e.g. 20oC from 18oC night setback - you need to increase the flow or the flow temperature?
increase flow temp..
Great video, for a Passivhaus with UFH, where the heat pump is going to be oversized, what would you do? Size the emitter as big as possible anyway to still run the HP at as low flow temp as possible and use the floor like one big buffer / storage heater, charging the extra thick 150mm slab once or twice a day? Would that still avoid short cycling and work with weather comp?
Still use wc and yes.. use slab as big store..
Is it cheaper to run a modulating system boiler and a separate water heating cylinder/heat battery or a condensing combi boiler
Is it possible to use weather compensation with 2 zones upstairs and downstairs controlled by a hive? Most evenings I use a wood burner downstairs, would this confuse the system? I have a Daikin 3 H HT with buffer and have had quite a few issues.
Just a question about weather compensation.. What happens if you were to go on holiday and want to turn off the central heating (empty house)... When you get back the house will be cold and you will switch the CH on.. With weather compensation it'll only lazily warm up rather than quickly attaining a setpoint (as the radiators won't be that hot). Is there any way around this? Other than modulating using load compensation... Or do some boilers have a weather compensation bypass for this scenario.
You would only set it to reduced target temperature. In the last 10 years I've not really had this problem.. radiator output will also be increased at the air to water dt is increased.. and there's holiday timers on decent controls to set it to warm for the day your back..
Great advice on the weather compensation but I think your advice on hot water storage temps might get a bit of backlash. Especially for elderly people who don’t use much hot water. Keeping your cylinder temperature lower than 50 degrees for a sustained period is not a sensible idea at all.
Nearly all our systems are kept at 48c. We also mentioned legionella cycles
Can you tell me your thoughts on thermodynamics and do you think it’s better than solar thermal vacuum tubes.
you mean thermodynamic pannels? absolute crap please avoid!
Hello,
Thank You so much for an in depth explanation ;
I have a Midea M thermal heat pump that has option on the wired controller between desired water flow temp and desired room temp - does that have anything to do with the weather compensation - meaning if i set the desired water flow temperature the pump will always try to hit that value ?
Thank You for your help !
If anyone has any info it would be much appreciated
How does this work if the daytime temp is say 29 and the evening drops to 10? Can a heat pump adjust to these timescales?
Yes..
For my vaillant boiler what weather compensation do you recomand?
What's missing is 1 pick opentherm boiler AND opentherm controls 2 install a weather compensator 3 Size your boiler not some lazy oversized choice by installers 4 If it's a replacement boiler , power flush the rads as part of the install quote.Either a hose appears or a power flush pump. 5 Home gets cold very quickly then invest in some insulation.Attics are the obvious choice but crap exterior doors, the PVC double glazing windows are not designed to be maintenance free for decades, cavity wall insulation is a no brainer and hidden benefit.
Can that viesmann boiler still condensate at 85 degrees when the outside temperatures are -30 although I doubt this would happen in the uk also I can't understand why all gas and oil condensing system boilers don't have this energy saving devise as it surety it wouldn't take much knowledge to replace the potentiometer with a circuit board with different resistances linked to an outside sensor
What you are envisaging is load compensation ie an automatic reduction in boiler temperature when the rooms are getting up to temperature. It's similar in principle to weather compensation but is responding to indoor temperature rather than outdoor. Very worthwhile. I believe Veissman boilers can offer load compensation.
Why does so little of the industry know about this
I am currently having a strange situation. The Vaillant air to water heatpump flow temperature didn't increase to the targeted temperature( 41 C targeted vs 37 C on the flow to radiator). Seems this is causing the heatpump part of flow temperature gets very high to near 60 degrees C. The electricity consumption also increased by a factor of 3 when this happened. Any idea how to optimize it? Or it could be a problem with the system?
I’m currently testing my heat pump system for the correct heat curve. Bad installation (long story) and I have to set the temperature sensor to water only. The main controller is in a bad location as it’s in a Utility room with a clothes dryer so using the air sensor is not an option. Would you advise moving the controller so to avail of the air sensor also? No matter what heat curve set points I choose, the unit is spitting out heat and house is too warm!!
I was wondering, are there optimal radiator designs for flow rate? Ie does a two column radiator flow better than a four column rad? or is there some other design altogether?
Not really.. designer rads ate crap but the others are similar
Very well explained, however I’m an Architect!
I fear this will be too much when trying to explain to clients.
In saying that, the installer should ask three or four questions prior to set up, to take all this out of the clients mind!
Very much appreciate the video tho! 👍👍👍
Every single housing estate in the country probably has weather comp switched off 😡
Is it just me, or is this like hard work and complex especially for the older people, who just want to be warm and comfortable in their home 😮
Not just you. Everybody wants life to be as simple and hands-off as possible. However it's also important to save on energy bills as much as possible and that's what efficiency (COP) is all about. But this is not really aimed at the user, it's really explaining what the installer should do, ideally. And if the installer does all of this and gets it right then the user doesn't need to change much, ever.
Wanted to watch this, but had great difficulty hearing over the background noise. Therefore stopped trying after several minutes.
Condensing boiler without weather compensation here. My understanding was that for maximum efficiency, my flow temp should be 57 degrees apx. Will going lower bring more efficiency?
Yes, there is no magic temperature, whoever said 57deg. Your boiler efficiency increases as you lower the flow temp; mine is often reduced to 33deg at this time of the year. But it can't heat the house from cold at that temp, or at least it can't heat the house from cold quickly.