RV Rooftop vs Mini-Split AC | Shop Talk | DIY Truck Camper
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- Опубликовано: 8 сен 2024
- Specifications can tell you a lot if you can dive into them. So here's a walk through of RV AC unit specs, how to read them, how to compare different units and different AC technologies.
In this shop talk video, we document 5 types of RV AC units: rooftop (old and new), mini-split, window, and DC rooftop. We show how to calculate their corresponding efficiency and performance and get a real comparison. If you decide to jump into a conversion or upgrade, put your AC specs through the same exercise and then decide what will meet your needs.
Our DIY Truck Camper has a Mini-Split that is high efficiency and we can run (and do) on our solar / batteries. But was it the best choice? Take a look and let us know.
The spreadsheet and much more in depth article is also posted on our blog.
#RV Mini-Split #DIY #Engineering Explained
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This was really good info on some of the differences to look out for between different A/C’s. Split systems are definitely the go for so many reasons; efficiency, versatility, smooth & quiet running with generally many more features/ timers, follow me, SEER rating, COP, etc. something to consider when buying one though; type of gas, ie: Propane based refrigerants are generally more efficient, R32 seems to be ok, and must be a inverter type for efficiency and the soft starting reduces surges on ur inverter and batteries too. From what I have seen so far in comparing ac to dc type splits, is that for the price of a DC type air con, you can probably buy a decent 3-5kw AIO MPPT inverter as well and power everything as well with the money you save on buying a AC split system A/Con. Enjoying ur vids & ur in-depth mathematical & logical manner. Cheers
"Calculated Characteristics"....touching continually on questions one has is beyond appreciated Steve.
Blown Away!
So happy I found your channel! As a physician, I appreciate an engineer talking about my favorite hobby!
Welcome aboard!
Excellent info - you just swayed my ac thinking 🤔 to a lg mini split. Thank you
Thank you for taking the time and making this video and collecting and presenting the data! Just found your channel, I was getting tired off all the misconceptions and terrible technological understanding many other videos had. As an engineer I appreciate when someone can present data and actually understand the physics behind it. Thank you!
I plan to do another update. It's been in the planning and preparation phase for about a year ...we're trying to build our forever house and are breaking ground in a couple weeks so I'm not sure when I'll get around to it.
Best video I could’ve found today
I have a Pioneer 9,000 mini split AC/heat pump in my van. It does a great job of keeping the van cool and sipping on the batteries and solar panels.
Great video 👍
Thank you. I'm glad your unit meets your needs. Premium brands typically are able to run as low as 30% capacity instead of the Pioneer's approx. 60%, allowing it to consume much less power if only a little cooling is needed.
@@WorkingOnExploring your information would have definitely changed my selection. When I was looking I looked for information on the difference between the brands and Sadly couldn't find any. I live in the Charleston SC area and it runs 24/7 thankfully off solar panels (1,200 watts) on the roof of my van and 900 amp hours of lithium batteries.
@@Scrambler85 Its a bit challenging to dig into specification sheets if you are not experience with it. On the LG and Pioneer 'submittal' sheets (both available with all my comparison data on my blog at workingonexploeing.com/techdocs), they show 'rated' capacity (100%) and two other capacities for a short termi high speed mode and a low speed mode. THE WAY to keep your A/C most efficient is for it to never turn off but to just slow down. It may seem contradictory but variable capacity A/C units get (MUCH) MORE efficient at low speeds.
@@WorkingOnExploring on economy setting it pulls 187 watts and on turbo mode it pulls around 1,000 watts.
I will take a look at your blog.
👍
Eco at 187W sounds too low for the compressor to be running but too much for it to be just fans. According to my spreadsheet, the WYS009AMFI19HLD has a low speed capacity of 5.8kBTU drawing 292W which is an EER of 19.9 (exceptionally good) but my LG has a low speed capacity of 3.07kBTU but no comparative power spec. I can't recall if I've measured it....
You killed it King! Nice job. Wish I would've seen this prior to outfitting my bus with a RV roof system. I will pass this on to my friends in the food truck industry. Thanks for all of your excellent efforts.
Thank you so much for sharing this information. Its one thing to know mini splits are better, its another thing to understand WHY and how much better they are. Now the tricky part...how to hide/mount a mini-split?
Very true. Most folks don't hide it and just park it on the rear bumper. I 'hid' mine by submerging it into the side of my chassis-mounted truck camper but unless you are willing to build your own camper, that is not an option. I know that some 5th wheel and class-A owners have managed to squeeze them into a bag box which is a good option but being larger RV's, it is a race between RV volume and A/C capacity to see which can fit. I think my more significant (unsaid) complaint is that the rooftop A/C manufacturers could easily build a unit with the same equipment at a similar performance, capacity and potentially price but they don't (more correctly won't) because there is little competitive pressure to do so. Having worked in building custom A/C units, the price of the 'old' type components they use compared to variable capacity is less than half....they are content with raking in a high-profit margin on underperforming equipment so long as they have no reason to do otherwise.
Wow! Great video, tons of information
Great work and thank you very much. The answer is easy to see.
Thanks. Good to know in not just seen as blabbering techno jargon.....I want to do some more comparison on 48V DC mini-splits which is where serious RV systems that want to operate EFFICIENT DC air conditioning will need to go.
My goodness I've learned so much about ACs in general just from this one single video! Very informative and educational and cuts through all the bs!
Glad to help...I have several others on A/C's...probably simplified by my not trying to sell you something...lol
Thank you.
This is an excellent presentation.
I would add the EG4 mini splits to the mix (9, 12, 24K BTU sizes).
The advantage of EG4 is their ability to operate directly off of solar as well as the normal AC/DC sources. This is very efficient for boon docking application when shore power is unavailable.
SEER ratings >29 are possible and the heat function works down to 4 DegF outdoor ambient temperature w/o needing a resistance or fossil fuel backup. 😎.
Thank you. I have been intending an update for some time but seem to keep myself to busy to find time. At present am building a shop /house in South central Idaho. There are a lot of new products on the market with interesting features that deserve attention.
That took a lot of work. Thank you for your time, I can’t say that enough!
Thanks. A/C is very necessary for a pleasant RV experience and I so very irritated that manufacturers don't build better equipment.
Wow, excellent job well done!
Thank you very much!
Another incredible video Steve. I've been debating between roof mount or minisplit and this seals it for me. Thank you!
Glad to be of service! Mini-splits are IT! I have to presume you chose the mini-split? I have thought many times about starting up an RV A/C manufacturing business that puts mini-split components in an RV-compatible package.....Its an exciting concept.....I guess I just want to stay retired more....
Long video, it VERY VERY INFORMATIVE!! Thank you for your time and efforts, I appreciate the education!
Glad it was helpful!
Outstanding work sir. The citizens of this country need people like you to work at the DOE to educate the political management about pure facts vs fiction. Very refreshing sir.
Thank you.....I am pessimistic about government ever developing an attitude of service to the electorate. As Groucho Marx is quoted as saying; 'Politics is the art of looking for trouble, finding it everywhere, diagnosing it incorrectly and applying the wrong remedies'. I am convinced, we are left to fend for ourselves and help others as best we can.
@WorkingOnExploring What a perfect synopsis. Over 40 years in construction and the last 17 as a government engineering and construction inspector, now retired. I can tell you that it is like rowing upstream with no paddle and people continuously punching holes in your boat and taking away any form of bailing device. However...it's so easy to circumvent the BS and make a difference every day for the taxpayers to not get robbed. The method to use for this positive outcome is assembling the basis facts and statistics on the issues and presenting them electronically to a broad range of principles and letting it soak in. Exactly what you have done sir. A few will respond, most will remain mute. One last email seals the understanding of my intended response and actions!
What an excellent research! Very comprehensive information on the subject covering from all perspectives. Thank you so much for the work and sharing this video.
I'm glad it was helpful. I am compiling comparisons of more units for a followup. I think I have 12-13 now. Although its not complete the latest spreadsheet is available at WorkingOnExploring.com/techdocs.
😄👍Good Stuff, Great Tips
The spreadsheet used is located on 'WorkingOnExploring.com/TechDocs as well as some other related into.
Oh my goodness! Thank you soo much!
Nice job. Great video much appreciated!
Thanks. I'm working on an update, comparing a broader array of DC and heat pump units that might get posted in a couple weeks.
I appreciate this information. I'm searching for my best solution. Instead of a van I am cooling a semi truck sleeper. Ultimately I want a low profile rooftop with minisplit efficiency. The inside unit would be bulky inside the sleeper. Rooftop would have no loss of useable space. I want something efficient enough to run off the inverter for short time frames or a generator for longer periods. Are there any products out there like this? I have not found anything yet that has this combination of physical packaging and efficiency. Heat will be done by a webasto bunk heater,, so cooling is much main concern. Thanks
You are looking for the 'holy grail'. I don't know of one right off because you are looking for a niche product with low capacity that is not suitable fo the RV marketplace, so let me ramble a bit.....There are several systems with different configurations. Since you are working with a small space, you likely need 5kBTU or less. This is really not the domain of mini-splits or RV units as they tend to be twice as large as you need. Having said that, there is really nothing other than a mini-split that uses the VRF/variable speed to attain the efficiencies they do..... Also, since you are needing to cool a small space and space constraints are more important, I don't think efficiency is as high a priority as space constraints and right size. Why are you not shopping for an APU (diesel engine driven AC alternator/DC alternator/refrigeration compressor)?
The marine market uses an IDU (evaporator and blower) /ODU (compressor, condenser, and condenser fan) arrangement, they typically have a DUCTED IDU that can be placed inside a cabinet (evaporator, blower, and compressor) and an ODU of just the condenser coil and fan that can be placed under the cab or behind the cab (like an APU). (CruiseNcomfortusa.com) is a representative brand and there are several others. They are very expensive.
There are also some DC units that appear more like RV units and are probably too large (and are UNREASONABLY expensive) but their smallest unit @2kW may work. see Nomadiccooling.com/. Rec Pro has begun making a DC equivalent for RV's that has too much capacity for you but is better priced (www.recpro.com/rv-12v-air-conditioners/).
I think a 120V 'window' unit would be most appropriate but would be ugly and require cutting a hole in your cab that I know I could find unacceptable. Some of these window units are headed toward achieving mini-split-like efficiencies but are still far from it.
Steve, I'm a huge fan of your very detailed work. As an engineer I appreciate this kind of analysis.
I'm building out a class B campervan (promaster 3500 high roof ext.).
Any opinion on AC vs DC mini split heat pump?
I love the thought of using a DC mini-split BUT (long story short), they are 48V. 12V A/C is mostly R134a/Automotive based and the high currents of ANY low voltage DC system is almost certain to be at best equally but more likely less efficient than a 120V inverter running a minisplit. I run a 24V system but should have run a 48V system. There are only a few 48V minisplit but they appear well made and efficiency is a primary goal. If you plan lots of A/C use (I prefer not to and hope to use my mobility to move to cooler areas) and will have lots of solar to support it (I do), it may make sense to go to 48V. I've been collecting data to compare newer rooftop A/Cs to DC to minisplit. The bottom line is most every unit running on low voltage has lots of loss in either voltage increasing or motor controls. Most lie about it (some quite effectively). I've been ferreting it out. Minisplit are residential units and are legally required to be accurate about their EER/SEER performance. There is no such mandate for A/C that is not installed in a residence (meaning everything in an RV or boat) but the The only real efficiency gains for DC powered are at or above 48V.
@@WorkingOnExploring That was above and beyond what I could have hoped for in a response, thank you!
Wow, this is one of the clearest and most helpful videos I've ever seen to help understand all the pros and cons of AC options! You brought up a point I was completely unaware of: the inherent inefficiency of 12v systems at high current. I thought that overall effciency was precisely the reason people spent $4,000 on these 12V AC units. Can you explain a little more about this 12V efficiency problem?
It's pretty simple really. The 'tool' for speed control (voltage or frequency conversion) for all electronics is the 'semi'-conductor. 'Semi' is intended to mean that it can be switched between a conductor and a non-conductors to be used as a switch/amplifier. While this is (obviously) true, it must be understood that while silicon CAN conduct, it is not as good a conductor as metals are. The fact they are less conductive (than metal wires) means that a portion of the electricity that flows through them is turned into heat.The relative portion turned into heat instead of flowing to the device is wasted and results in inefficiency. IF this loss were linear and proportional to POWER, the inefficiency would be the same for all voltages since Power = voltage x amperage. However the loss is not linear, it is EXPONENTIAL. The formula for power loss is: Power (loss) = current squared x resistance. This means for each doubling of current, the power loss is quadrupled. Said another way, for each doubling of voltage, the power loss is quartered.
As an example, let's compare losses in motor controls of a DC A/C unit drawing 1000W at both 12V and 48V (which are both commercially available). To control a 1000W load at 12V, the current is 1000W/12V=83.33A. The power loss is 83.33A^2 x R =6,969 x R (ignoring the actual value of the resistance because the same semiconductors will be controlling both motors). The 1000W/48V = 20.83A. Losses are 20.83^2 x R = 433.9 x R. The losses at 12V are 16 times more than at 48V.
This is true if using a brushless DC motor, a VFD on an AC motor, or an inverter. All are semiconductor switching devices.
For this reason, a 12V A/C unit will never be as efficient (by a lot) as a unit operating at higher voltage. 12V systems are inherently inefficient at virtually everything. EV's run on 360V (as does their A/C system) for this reason and are an electrocution hazard so there will likely be a middle ground voltage when the automotive, A/C and RV industries get around to addressing this problem, which they must if an electric RV is to truly exist.
@@WorkingOnExploring But a control unit designed for 12V won't use the same control devices as one designed for 48V. It will either parallel multiple devices or use larger ones (to the same effect), which lowers the internal resistance that lowers efficiency. As the supply voltage drops, everything in the circuitry has to get bigger to keep resistive losses low: cabling, motor windings, you name it. That adds weight, size, and, still, power dissipation (control circuitry has to be beefed up to drive those control devices) to the whole shebang. If you're using a 48V control unit for 12V compressors, you haven't done your engineering homework.
@@shaunsimpkins1395 I think your comment is correct but you misinterpreted the proposed system design. When I said the way to get into efficient, DC air conditioning, was to use a 48V A/C unit, I evidently didn't also clearly state that also required CHANGING the entire DC system (all new equipment) from 12V to 48V (NOT using a 12V-48V DC-DC converter). I don't think I inferred using a converter, at least I hope I didn't. If that is what you thought I meant, you are correct, that would be crazy.
The efficiency of using a DC-powered A/C unit is in 1) minimizing power conversions and 2) reducing the current. Step 1 is to use the same power system and equipment voltage. No conversions = no conversion losses. Step 2 is there are always motor control losses if using variable-speed equipment. Power loss relative to current is expressed by (P=I^2*R), Power loss = Controller/motor current squared times resistance. First look at the current; By increasing the voltage 4x, the current is 1/4x which means we reduce resistive losses (1/4)^2 = 16x. Second, look at controller resistance; The motor resistance will increase but the controller components will not. As we are looking at controller losses, R1 = R2.
Anytime, we are either converting or controlling low voltage DC, we have high current and therefore low efficiency......I think we agree on all of this. I think your concern is thinking I was expecting to convert 12VDC to 48VDC which I was not.
@@WorkingOnExploring Thanks for your response. Let's take a simple example: a voltage source of Voltage k*V - where k is a voltage scaling constant - driving the series combination of a resistor of value k*R, representing connection and control unit losses, and a motor/compressor unit with a load resistance of Rm * k. Efficiency can be defined several ways - electrical, size, etc., but let's define it as the power dissipated by the load divided by the total power dissipation of the circuit. We can write i= k*V / [(R + Rm)*k] = V/(R+Rm). Total power is ((k*V)^2 / [(R+Rm)*k]=kV^2/(R+Rm). Power in the motor is Rm* [k*V/(R+Rm)]^2=Rm*k*V^2/(R+Rm)^2. Efficiency is Rm/(R+Rm). Independent of k, but ONLY if all components of the circuit scale by k in the manner implied.
Reality being what it is, there will be constraints on how well the components of the circuit can scale; cable size and weight may grow too large and heavy to be practical; the compressor windings may as well; the control unit, with its switching transistors, may not be upsized enough to handle the increased current. You've implied this in your I^2*R discussion - it's assuming that R remains constant, and in that case, yes, power dissipation will increase 16 times for a 4 x decrease in voltage.
Bottom line, lower voltage systems DO tend to be slightly less efficient than high voltage systems if the engineer has done their scaling job thoroughly, but not an order of magnitude less efficient. That slight difference I think arises from practical design constraints, not fundamental limits.
I think in the baseboard of a truck camper the 5-6k BTU is more efficient at 110v around 500watts. Great and informative video, thank you.
I've been running it quite a bit lately. The broad operating range of 3kBTU - 10.5KBTU is really helpful for efficiency....If I start it around 1PM, it runs at about 800W (full speed) till it reaches set point then slows down below 400W. As peak heat is about 5PM, it creeps back up to about 600W then to keep it cool. The 950W of solar typically put out more than the A/C draws till about 5PM then it starts pulling more from the batteries.....I've found as long as it's less than 95F, we can probably recover enough battery charge by noon to replace what we've used running in the evening prior...
@@WorkingOnExploring check out the softstart dog bone for 30 amp.
Variable speed motor controls cannot benefit from or use a 'soft start' which can only be used on a single phase induction motor.
@@WorkingOnExploring that is why I believe the window unit would benefit from it.
Most variable speed compressors use variable frequency drives which are supplied by single phase, 60hz power, converted to DC and then 'inverted' back into 3 phase AC at a frequency that corresponds to the desired motor speed. They are inherently, 'soft starting' because the VFD has the ability to ramp up motor speed gradually. Putting a soft start designed for a single phase motor on the input will not affect the VFD control or be able to change the motor speed..
Incredibly well-researched. TY for the content. I'd like your thoughts on these "backpack mini splits" that have hit the market in 12v and 24v varieties from overseas and are much more cost-effective than other DC cooling options? Would the 24V flavor make you more interested in pushing that DC motor efficiently without the conversion loss of an inverter? Thanks again, and happy travels!
With 'single stage's A/C @ 120VAC, there are 2 main losses; 1)in the 12V-120V inverter due to high 12VDC currents, and 2) the 65% efficient single phase motor. With single stage DC @12V, there are still the same huge DC current losses, this time in a motor controller switching the same current as an inverter. The BLDC motor can have higher efficiency BUT ONLY at higher voltage. The defining equation for power dissipation is : P = (I^2) x R. The killer in power loss is any high current when squared becomes huge.
Assume for a moment a 1T/12kBTU A/C that might require around 1200W to operate. That is 100A, when squared is 10k. Assume the resistance is 1. Power loss is on the order of 10k.
Assuming a similar capacity unit operating on 48V. Current is would be 25A and resistance would be 4. P = 625 x 4 or 2.5k. Increasing voltage by a factor of 4 decreased resistive effects by 4, meaning increasing efficiency by a factor of 4.
The critical problem is that starting at 12VDC will always be a killer. DC air condition only gets significantly more efficient at 48V or higher. The antiquated standard of 12 and 24V automotive systems will never allow efficient A/C and the sooner dispensed with the better. EV A/C systems are 360V, just like the drive motors and that is a voltage where losses are pretty low and motors pretty efficient.
Just going
@@WorkingOnExploring ok, so the benefits of not having to convert from DC to AC are outweighed by A) the inefficiency of running a DC motor at low voltage and B) the single stage motors in these "backpack mini split" devices (I wasn't aware, I thought they ramped up! :o). Many thanks!
I'm not sure what you exactly mean by 'backpack'...modern, name brand mini-splits are most all 'variable capacity' which is accomplished with 1) a variable speed compressor. The variable speed is accomplished using a 'variable frequency drive'(VFD) which marketing idiots usually/incorrectly call an 'inverter'. Induction motors operate at an RPM corresponding to the input frequency. Being able to bring in single phase 60hz/120VAC, convert it to 120VDC, then converting it back to 120VAC/3 phase at frequencies from 20hz to 90hz allows use of a more efficient 3 phase motor (80%) at speeds from 1200rpm to 5400rpm and some associated capacity thereof. The efficiency loss in the VFD is more than made up by the increased efficiency of a 3 phase motor. The variable capacity allows the system to run continuously and thereby eliminate the efficiency loss of start/stop, which is considerable. 2) variable speed requires a more capable expansion device to control the wide range of refrigerant flow so they also need an 'electronic expansion valve' (EEV). 3) The type and number of compressor mechanisms is also a factor. The best use a 'scroll' mechanism with two scrolls offset by 180 degrees much like a dual piston compressor would have 2 pistons offset by 180 degrees. The scroll mechanism is not only much more efficient than pistons, it is capable of maintaining that efficiency over a large rpm range.
Just because you have A/C equipment called a ' mini-split' does not mean ANYTHING about how it is constructed. An awful lot of RV equipment is ancient technology because there are no regulations requiring them to be more efficient which there very much is for residential equipment. If you really want to compare equipment, you need to parse the specs and marketing BS to figure out what is in it AND how it is operated. The devil is most definitely in the details. You cannot just pick one type of A/C unit and compare it to another unit of the same type and size and expect you are comparing apples to apples.
I think there are some resources on my blog, WorkingOnExploring.com/TechDocs that may compare some issues but I can't recall exactly what's there.
@@WorkingOnExploring Still digesting your comments, but these new "backpack mini-splits" that have hit the market recently from China can be found by searching YT for "backpack mini-split" and also searching for YT videos under the name brand "Treeligo." Many thanks for the detailed response.
Excellent analysis. Amazingly, the coefficient of performance, COP, for your mini split heat pump is 3.65 ( > 1), which means: what you get for heat is 3.65 times of what you pay for the electricity. It's a very good deal for energy conservation. Theoretically in thermodynamics, the COP for Carnot cycle (idealized heat engine) heat pump is always greater than 1. I was impressed by its efficiency when I was taking the class in school. The mini split you have should be very energy efficient for your winter heating. Do you have any data for that? Thanks
I have taken quite a bit of data on A/C but not on the heating. We do use the heat pump a lot when we are on shore power at our remote property or in someone's driveway but we don't use it much for heating while boondocking in the winter because COIP is lower and our solar collection is only half what it is in the summer, (due to the low sun angle, lower daily hours etc.). When boondocking in cold (30-40F) weather, we mostly use the diesel air or coolant heater for cabin heat as COP goes down with temperature differential. Since it can still produce heat down to 17F @ a COP of ~2, its always a good idea. With A/C temperature differential of ~20F and heating temperature differential of likely more likle 30-40F, the COP is not as compelling for heating use as A/C. If you really want to be impressed by COP, check into air to water heat pumps. I'm working on building a home in Idaho and plant to have hydronic in-floor tubing with an air source heat pump. Because the delivery temperature for the hydronic only needs to be 90-95F instead of the 120F or more for air to air heat pumps, the COP goes from ~3.5 to 5 or even 6.
I'm planning on adding a Hotspot 48v DC mini-split 12,000 Btu heat pump to my motorhome later this year, to be powered by a 15kwh 48v LiFePo-4 battery bank recharged by 3,000+ watts of solar. I would like to see a comparison for this very high efficiency (EER of 19.3) DC4812VRF
DC unit compared to one of the ultra-high efficiency 30.5 seer 12k Btu 220v AC heat pumps, like the GREE Sapphire. In this application efficiency is much more important than price because any price difference would be easily offset by batteries and solar panels cost and weight savings. What I find interesting is that the GREE has a 14 HSPF for heating (compared to 9.6 for the Hotspot), so it seems optimized for heating as it's cooling EER is only 15.3 compared to 19.3 for the Hotspot. I guess I have to add in the inverter loss for converting 48v DC to 220v AC too. Your thoughts?
My apologies for being slow to respond....I absolutely think going with a high efficiency 48VDC mini split is probably the most efficient way to delivery AC from a DC supply. Most are optimized for A/C not heating but I will do some research on it and get back to you but it will likely be a while. I am deep into a hydronic heating project and we are trying to get ready for summer travel. Some thoughts to ponder; 1) Assuming the 48VDC unit uses a BLDC motor (almost certain), its efficiency will be hard to beat with an AC unit if you take into consideration the efficiency loss of the inverter. 2) Efficiency gains in residential A/C have been mostly running variable speed compressors driven by induction motors and there is still a lot of the mass residential market that has not experience that (other than mini-split). I think the next step in improving efficiency of AC powered air conditioning will be when one of the compressor manufacturers replaced induction motors with Synchronous Reluctance motors. Someone may offer it but I have not become aware of it. My bet would be that Danfoss or LG will do it first. They have the competence and market drivers. 3) Higher SEER ratings rely on larger coils (mostly condenser) which is contrary to what RV applications tolerate. There is little tolerance for a bigger 'wart' either inside or outside the RV. 4) If both the indoor coil and outdoor coil are similarly enlarged, they can reach high SEER AND HSPF ratings. If you see one lower than the other, it will usually be because they only enlarged one coil not both to optimize in favor of one operation. European demand is driving hte heat pump efficiency improvements. They have much more demand for heating and little for air conditioning as they have been for moving away from fossil fuels (natural gas) to electrically powered heat pumps. Russia cutting of gas will really drive that. Manufacturers have responded by improved heating, which is a newer (in the last 10 years) trend. Not only improving HSPF but also 'low ambient' operation. I think you are wise to pick up on that and prudent to shop for the qualities you most want. My LG mini-split has better heating capacity than cooling (typical) but I dont think I would have made a choice to look for one that did. Not that I am about to build a house in Idaho, I am definitely looking for that. I think AC powered units will see lots of heating and efficiency improvement in the coming decade but suspect little will trickle into the DC or RV equipment.
@@WorkingOnExploring Thanks for the detailed and well reasoned reply. You've given me lots of valuable insight. I think I'll stick with the 48v DC Hotspot, as I'm more concerned with air conditioner efficiency, using the heating function as supplemental heat in milder seasons, simply to save some propane. It seems like a simpler, more straightforward way to go too. Propane appears to be an ever increasing expense though. I've recently paid as much as $4.59 a gallon for it at a Loves gas station while traveling.) Also, if I'm boondocking deep in the forest, I must consider the cost of the added trips to and from the propane fill station, as I have a large ASME tank in my MH and not the portable DOT tanks that trailers use, which can be transported in a smaller vehicle. The specs on the hotspot say both the inside and outside fan motor is a Panasonic BLDC, and the compressor is a GMCC Toshiba unit, which I assume is their high efficiency ASM108D13UFZ model, though this is just a guess. I really appreciate taking the time to answer me. Chip
@@SuperSushidog Chip,
I'm grinding through my comparison of units with new types, including the Hotspot. I'm still not done but wanted to confirm to you that it seems to me to be the BEST CHOICE if you're ok with 48V power. The EER is 12.2 compared to my LG at 12.3. Be careful because the Hotspot's operating range is 46v-59V. Cutoff is not as low as I would expect and potentially a problem with LFP batteries. 4x 12V LA batteries at 50% SOC cutoff would be 48V and full charge at 50.4V. With LFP batteries , a normal 16S would give you a cutoff voltage at 2.5VPC = 40V. The range of 16S, 17S or 18S all present problems at the limits. If you really want to use the A/C over full battery capacity, you might consider 18S (45V-65.7) and run between 46V (2.55VPC) and 59V (3.27VPC) which is probably only using 70% of total capacity.
@@WorkingOnExploring Thanks for the reply and the advice! With a 16s LiFePo-4 bank 100% SOC is 54 volts and a 9% SOC is 48v according to the charts that I see. Since I would be operating the battery in the 95%-10% SOC range, for maximum battery life, this shouldn't be a problem, as the voltage requirement of the 48v hotspot (46-59v) falls within this range. A 17s bank will have a range of 57.4v-51v (at 9%SOC - which I would set the low voltage cut-off on my BMS for) which might serve me better and should still work with the PIP 3048LV-MK 48V 3kW 120V Inverter/controller/charger I plan on using, as it has an upper voltage limit of 64v. watts247.com/product/pip-3048lv-mk/ The user manual for this device says that it will charge at a maximum of 64v, which is more than enough for a 17s bank but 1.7v shy of what an 18s bank requires. Next step would be finding decent a 17s BMS, as I'm not real crazy about the Daly. Any suggestions?
@@SuperSushidogFor EVE type lifepo4 cells, I like the 48v 20s20p 200-350A JK BMS’s with a 2A active balancer they work really well, look on Ali express. Real interesting convo & info guy’s, I have a 24v system in a bus & a 48v system at home. I have a 2.5 kw inverter split on the bus and it works quite well off a 3kw AIO 24v system & 10kw lifepo4 + 2kw pv so far as it is a reckless abandon on another property 400+kms away.
I dont know enough info here, but my immediate take on the 48vdc split system idea is that , yes it would typically be much more efficient than a 12vdc split, but I am guessing this 48vdc split is a lot more initial cost to buy than a 120v-240vac split (Im in Australia, 240vac ), my 24v 3kw AIO system only uses a maximum of 1600w for a short time before ramping down to 300-600w mostly, what my gut is telling me, while I love the idea of a 48vdc split air con, is that it would be more cost beneficial to get a 120-240vac split & maybe get another 3kw inverter as backup or upgrade to a 48v 5kw inverter/AIO whatever to power ur A/Con, also if anything goes wrong down the road, it would be easier & cheaper to fix or replace the household split with another unit in a pinch. Other considerations might be to definitely get a Inverter type A/Con and a propane based refrigerant type, like R32, as I believe these are probly one of the more efficient COP type gas of today.
Also, if using a household type split on a bigger van or bus is not so bad, but consider how much vibration it may be susceptible to, as some may need extra high density foam/ bracing/springs etc, around compressor & piping area internally as they are designed to sit on a wall not a van and flexible piping at least in critical area’s is probably necessary in most cases.
How much is ur 48vdc split going to set u back??? Compared to a much cheaper 120-240v type? I am of the opinion that for the huge amount of power that Air Conditioning uses anyhow, the small amount of potential saving in watts between the ac & dc types is not going to be cost effective to go the dc route as you have to use inverters somewhere in these newer systems ac or dc to make them efficient anyhow. I dont know how much you plan on running ur A/Con, but generally they get used if & when you can, secondary to everything else you need power for first. Just my 2 cents. Cheers
Hi Steve....I will try to learn the formulas but i do not know them. Is there a formula that you used that i could borrow that would allow me to calculate how much battery I would need to run the LG dual inverter mini-split for two time lengths: 4 hours and 9 hours, at the lowest output, mid level output and maximum output. the system Im assuming you have is the ls090hxv2. Or if you can estimate that based on your experience. . i know you have a 300 pound battery pack i would like to use the lightest battery pack that could possibly meet those time and intensity need. Thanks if you can answer. I know it might look like i am avoiding work here, and I probably am haha.
Its a complicated question and therefore a complicated answer. Since there are many variables, inevitably AN answer has a broad range of 'possibilities'. In order to attempt to come up with something you can use, it is necessary to construct a 'power utilization curve' shown in my 'A/C 8 hours per day' video ( ruclips.net/video/ijk2Z-ebevw/видео.htmlsi=HEfq2G1I1yhxIvsV). Equipment consumes energy. That energy has to be supplied by something. When supply is less than consumption battery can make up for the difference. To determine battery size, you need to estimate supply and consumption (both very much based on physical and environmental conditions). Since I am assuming you are looking for a non-shore power solution, your supply side sources are generator and solar. The generator is not time-based (you can run it any time you want) and can be a replacement for a battery, but solar generation is time-based (solar generation depends on your capacity, mounting, cleanliness, time of year, location etc....it 'depends' a lot). You need to estimate your production hourly throughout the day and come up with a curve. Secondly, you need to do the same for consumption, not just from the A/C, but from everything else that operates daily. You really need a power meter on anything that runs intermittently or variably like your A/C. A 'kill-a-watt' meter is a portable version. This tells you what your instantaneous consumption is and cumulative consumption. I have something similar permanently installed. Your tests and estimates need to be done with your specific RV included. Size of the RV, insulation, ambient temperature, sun exposure, window type and area, etc, all factor in. This gets to heat gain/heat loss understanding. These factors have a MAJOR effect on how much your A/C draws when it runs. When you grind through these estimates, the shortfall between generation and consumption is your battery size...
QUESTION/IDEA: based on your information, it would be better to get a 110/120 volt minisplit and run it with an inverter instead of using a 12 volt minisplit. Is there a relation to the battery usage, like a bank of lithium batteries?
As far as I know, there are no 12VDC or 24VDC minisplits. They start at 48V for a good reason. High current resulting from a low voltage power source causes a lot of efficiency loss. Power loss is relative to amperage.
P (power loss in watts) = I (current) ^2 (squared) x resistance.
For instance, assuming the same semi-conductor motor control can operate a BLDC at either 120VDC or 12VDC. If the A/C draws 1200W (for simple math), a 12V motor draws 100A while a 120V motor draws 10A. The power loss (since we are looking at power loss in the motor control which is where most of it occurs), will be 100x larger in the 12V system. No matter high the efficiency of a BLDC may be, multiplying the power loss of the SYSTEM by 100x makes a huge difference. Something similar happens in the 12VDCto 120VAC inverter so you can't really escape the problem of using low voltage.
Higher voltage DC is where its at. EV's use 360VDC and so do their A/C units. 12V A/C will NEVER be very efficient until room temperature superconducting switches become commonplace (and there is a lot of work being invested in doing that).
The fact that the volume and motivation to improve the efficiency of A/C is in the residential market AND that the solar market is driving efficiency gains in inverters (operating at high DC voltages un the range of 100-600V) mean it is likely going to remain more efficient to operate an Inverter/120V mini-split than anything on 12VDC. There already is a movement to go from 12V to 48V in RVs. The 48V mini-splits are driven by the off-grid and tiny house desire. It is not making a lot of headway. I think it will be a race to see if 48V mini-splits or 360V EV A/C becomes a dominant force in RVs.
@@WorkingOnExploring electricity/amps etc confuses me silly, so thank you for the explanation. I still don’t understand half of what you said but I get the basic premise: 120V is more efficient. Thank you!
Power (rate of energy draw in Watts) is universal. Power = current (in Amperes) x Voltage ( in Volts). Devices can be made differently to operate on the voltage of the available power system. An A/C unit of a fixed size can be made to operate on 12VDC, 120VAC or 240VAC. If that unit draws 600W, the math to figure out it's current draw is the same: P = A x V or rearranging that formula; P/V =A. At 12VDC, 600W/12VDC = 50A, at 120VAC, 600W/120VAC = 5A, at 240VAC, 600W/240VAC = 2.5A. these equations are linear so all computations are obviously similar.
Power vs current equations are non-linear. The exponential nature of P = I^2 x R means that anywhere current doubles, power goes up 4x. Now Resistance is not the same but resistance will changel linearly. With one factor down linearly while the other factor goes uexponentially will mean there is the result will still be exponential (a doubling of inputs will produce an output that more than doubles).
Power dissipation is P
@@WorkingOnExploring Seems that the best way is a 120V mini split on a proper inverter is best. I guess 220V would be better, but standard here is 120V or so I understand.
Hi Steve,
I had a question on condenser size for which I'm hoping you may know the answer.
I'd like to use the propane bay in my Lance 1191 to mount the condenser on a slide out tray. When in use, I'll slide the condenser out so it has good ventilation.
The space in the propane bay I have to work with is width of 26", a height of 23" and a "thickness" of 17.5".
Most condensers seem to over 30" in width.
--Off the top of your head, do you remember any mini split brands that had condenser widths 26" or less?
The systems I've surveyed so far are all wider than 26".
Thanks!
Mine (LG) is the smallest 9kBTU I could find at 10x20x30. You're right in that most I found were 32" long plus you'll need a couple more inches on both sides. I doubt you'll find a 9k small enough but there are some 6k units out there. It's going to be really hard to find something.
I WOULD NOT MAKE IT MOVEABLE. There are NO flexible line materials rated to flex when charged. Van guys are doing it with Rectorseal flex stubs but thrse are installation aids, not for flexing under charge. I constantly recommend against it but I do think they are doing it anyway. I had one guy say he was going to use hydraulic hose. R410a refrigerant under pressure will pass right through rubber (slowly but enough to lose charge in a year).
If youre determined, you'd be better off with a marine multi- part unit that uses R134a that can use 'barrier hoses'. 'CruisenComfort, Mabru, MarinAir and Domestic all make that type. Many are low voltage DC. ALL are expensive.
@@WorkingOnExploring Thanks for that info!
do you have a link to the just the spreadsheet so that I can edit the different units? I'm trying to compare 30 mini splits to determine the best cost/value/performance unit within a set budget. Thanks in advance.
If you go to workingoneploring.com/techdocs, about half way down, you will find 3 files regarding A/Cs. The third one is the spreadsheet (excel file) I use to compare units. This edition has 12 units presently loaded. I recommend that you just delete my data and put in your own, keeping the columns and rows intact so they calculate correctly. You will also see a number of graphs that will help to compare 'calculated data' from each unit. This spreadsheet is still a working tool for me so I can't verify that there are not still some errors in places but it should help you.
Some advice not previously noted;
1) The 'turndown ratio/rate' is the ability of variable capacity units to operate over a large range. A unity that can operate between 30% and 100% (like my LG) is said to have a 70% turndown. For optimal operating efficiency, you should look for a unit that has a large capacity range. Ideally, you would like enough capacity range that the unit can operate on high to bring the high temp into a liveable range, then slow down to maintain the temp without having to shut off the compressor. Cheap units only have about 30% turndown. Some units also have a 'turbo' mode where they can operate at ~120% capacity for a short time to get additional capacity and cool a room down quickly. This is important but does not factor into the turndown calculation.
2) Variable speed = variable capacity and is essential to efficiency BUT, some compressors are just '2 stage' meaning 2 capacities. Make clear distinctions between variable capacity and dual capacity because they will try to fool you.
3) 'Inverter' means that it uses single phase power through a Variable Frequency Drive (VFD) to operate a three-phase induction motor at variable speeds. Not all compressors or VFDs will operate over the same range. Dont confuse single-phase input power with the three-phase motor because the VFD makes that conversion. It takes a more sophisticated design to have a broader operating range because the refrigerant metering device is also involved. Low turndown compressors typically still use a Thermostatic Expansion Valve (TXV) while high turndown units use an electronic expansions valve (EEV). Some compressors are also brushless DC (BLDC) designs that also use an electronic speed controller of a different type (but typically not called an 'inverter')
4) if you see the word DUAL, it typically refers to a compressor with two (typically scroll) compressors on the same shaft. it is a similar concept to a single-cylinder engine compared to a two-cylinder one. Two produce smoother and more capacity than one. A DUAL compressor of the same size as a single will have a similar capacity but the dual will achieve the capacity at a slower speed and be quieter with less vibration.
'Cheap' (inexpensive) units will not be the highly efficient design I assume you're looking for.
Be great if someone could figure out how to make a mini split outdoor unit into a horizontal form factor for RVs so they can replace the rooftop A/C unit without losing the efficiency and noise pollution of the current heat pump roof mount A/C units.
I see it as an 'easy win' for any of the rooftop A/C manufacturers to do exactly that. Even more, for a mini-split manufacturer to break into the rooftop A/C business. IMHO, the ideal package would be to make a 'horizontal' out door unit (ODU) that can sit over the 14" roof opening (or anywhere else on the roof) and feed refrigerant lines through the roof opening and have a thin (less than 3") ceiling unit (several manufacturers make 'low wall' units that thin) that could be mounted on the bottom of the 14" opening ( or like the ODU, could be anywhere inside on the ceiling). I think the existing manufacturers are unwilling to do it for fear of setting off a competitive race. The crap they currently make likely has high margins and new products cost money to develop.
@@WorkingOnExploring maybe a newcomer will take on the challenge 🙂
So what will be the best most efficient and durable mini split to put on a semi truck thats a condo sleeper to run off generator and shore power or maybe battery bank? Thank You very much.
Might get in trouble making assumptions about the size of a 'condo sleeper'.....what is the volume of the sleeper, and the insulation. Most Mini-splits, even the smallest 9kBTU, are going to be too big for even a big sleeper. Too big is a problem, even for variable capacity A/C. Single stage A/C comes on and off. To be efficient, they need to be 'on' about 50-70% of the time and ideally don't come on or off more than 2x per hour. A small space makes them start and stop very frequently. Variable capacity A/C runs over a speed range of 30-100%. It wants to run all the time and just slow down when the cabin reaches temp. With too small a space, it will be forced to shut down lest it over-cool. My vision of a semi truck sleeper is maybe 6x8(?) = 48SF? Rule of thumb sizing for (residential) A/C is 400sf per ton (where 1 ton = 12kBTU). This makes a 9kBTU unit suitable for ~300SF. This square footage is for a well insulated house so assuming a poorly insulated RV (or sleeper), may be appropriate for half that (~150SF?). In any event, I'd say that a (any) mini-split is likely inappropriate for such a small space......unless I'm wrong on my size assumption.
@@WorkingOnExploring I agree with your logic and assumptions, however I have had a couple of splits fitted on the roof of a Seedgrading Machine Cab Truck I used to own for years in outback Queensland Australia, and from my experience (and I never had inverter types), I would guess that this guy would actually get a good experience from any small inverter type A/Con in his Cab Sleeper. I know a number of Truckie’s who use different type of A/C’s in their rigs/sleepers. Without knowing his particular situation I would say it is always better to lean on the worst case scenario as a truck can go from freezing to very hot conditions regularly, in which case I would say it is still always better to err on to have more aircon capacity than needed rather than less, regardless of efficiency (to a reasonable degree), and he will probly have more than enough power onboard to run a A/C on battery for the few hours of sleep he will probly get anyhow.
Keep up the truth . I know your going against the grain w the manufacturers who need the more turnover vehicles .
great video, was looking at the diff AC options. my only question is that I noticed the mini splits were 3PH. So, 230v, Is that available from an RV park? Will these work with a 30amp adapter? Perhaps you should have included a 115v unit instead for comparison?
All the unites compared are 120VAC or 12VDC. All 'inverter' minisplit use a 3 phase, motor. In our case we are using a 120v 3 phase motor driven by single phase 120v power through a variable frequency drive(VFD - incorrectly called an 'inverter' by the marketing folks)....I understand your confusion....if you are not familiar with variable frequency drives, you couldn't have known this....single phase motors are about 10-15% less efficient than three phase, they require a start and a run winding, capacitors to start and run, a centrifugal switch to go from start to run.....lots of hardware... A 3 phase motor is just 3 coils and can be reversed easily, have higher starting torque.....a VFD operates by first converting the AC input to DC then converts the DC back to AC at the frequency desired to make the motor spin at the correct speed (the section in the larger device that is the VFD that does the conversion of DC to AC is the 'inverter' that what people are familiar with) . 60hz will run a single pole motor at 3600 rpm (60 revolutions per second). 30hz will run it 1800rpm, etc. This is the best method to make a variable speed, induction motor AND also a method to increase efficiency AND get variable capacity...
Alibi...I have updated the spread sheet with 6 more units and it is available for download at WorkingOnSExploring.com/tehchdocs.....Its I still plan to dual, inverter window unit to it and some sound data needs to be found but its pretty interesting. One of the units is a SEER 38, 240V mini split unit a viewer asked to be added and another user asked for a 48VDC minisplit....normally, I'd be with you, wondering what nut would use 240VAC let alone 3 phase for an RV. The SEER 38 is an absolutely amazing machine. On one hand, if you're paying for power in an RV park and have 240V/50A why are you too concerned with efficiency? On the other, if you go to the effort to put in a split phase inverter and all the solar and batteries that would need to go with that, it would be far from small but you could be the king of the boondockers!
I hope my first reply makes sense to you.....I did it from my phone while I was also trying to make dinner....so I did notice less than excellent grammar in my explanation....if anything doesn't make sense, feel free to come back...
@@WorkingOnExploring ok, now making sense, I understand varriable freq motors, I've never heard them called inverter motors before.... also you listed 230v on your spread sheet. Now the comparison makes sense... you have a lot of patience to put all this data together... due to your work and comparisons when my roof ac's fail I will replace them with mini splits... i've installed normal house spit units but never a mini split in a moho, sound like a fun project...
The A/C marketing lingo uses the term 'inverter' for no good reason when it refers to a variable frequency drive....they make it worse by using the term 'dual inverter' which is a misnomer but it rolls off the tongue....they are actually talking about two separate aspects of a compressor. 1) 'dual' refers to the use of two scroll compressors on the same shaft but 180 degrees out of phase. This is functionally identical to a two piston compressor in which the pistons are 180 degrees out of phase which both have the effect of increasing capacity and decreasing vibration....in the case of pistons, it is so obvious, it requires no explanation (and never gets one), the same is also true of two scrolls but the liars in marketing are always trying to make something out of nothing......the 'inverter' (as previously stated) is simply a more familiar and easier term to advertise than 'variable frequency drive', although technically incorrect......they also are trying to use 'inverter' when they are talking about the electronic speed control of a brushless DC motor which is a very different animal but the liars don't really care...
I like the idea all around with the mini split but haven’t heard anything bout the inverter, do you need to upgrade or can you stay with original one ? , should you have it on a separate breaker
I'm not sure if your question is about the 12V/120V (power supply) inverter or the (speed control) 'inverter' inside the mini-split so will try to answer both questions because they are related. The mini-split 'inverter' is misnamed by the marketplace and actually refers to the Variable Frequency Drive (VFD), of which an inverter is one of the parts of the VFD. The VFD is the speed control for the compressor. One of the virtues of speed control is that it can start the compressor slowly and speed up to whatever it wants without EVER overdrawing its run amperage. Said another way, there is no 'starting surge' that is prevalent with single-speed compressors. The lack of a starting surge means a mini-split does not need an oversized (power supply) inverter on which to operate. Again, as with single-speed A/C RV roof units, a 13.5kBTU unit may have a running amperage of ~12A (~1.45kW) but the starting amperage is probably around 2.5kw. The (power supply) inverter needs to be sized for this starting load so would likely need to be 3kW. In my case, my 9kBTU LG mini-split has a full load amperage of ~8A (960W) so I could run it on a 1000W inverter if I wanted.
As an aside, 'high frequency' (cheap) inverters frequently are marketed as having a 'surge capacity' of approximately double that of the continuous duty capacity. What is unsaid, is that surge capacity is only available for under 100mS, which is not long enough to start a heavy motor load. It is effectively a deceptive marketing ploy. They do it because 'Low frequency' inverters (that have a large copper wound transformer inside, are heavier and significantly more expensive), also have a similar surge capacity but their surge capacity is REAL and lasts anywhere from 10-15 seconds to 10-15 minutes.
In electrical branch circuit design, there should be a breaker AT the source of power to protect the downstream system (the wiring). For a receptacle circuit in which loads are small and a single circuit can run multiple devices at one time, having one breaker to protect multiple receptacles is fine. It is understood that not ALL loads can or will be operating simultaneously. For large, single loads it is necessary to have a dedicated breaker so that it has (because it needs it all) the complete power of the entire circuit and no other intermittent device can load a portion of the circuit, leaving too little for the large appliance to run.
@@WorkingOnExploring terrific this helps out a great deal , there’s a lot of installment videos about these mini splits but like I said none bout the electrical and or inverter
Thanks again you’ve been very helpful it made my life easier and less problems down the road
@@WorkingOnExploring oh thank you for getting back
Awesome vid, wish you would have compared it to a cruise n comfort. Also whats you’re thoughts on the cruise n comfort?
I looked at their website (again) based on your question. They, like so many others that don't have to provide standard performance data, they don't. What they do provide is obscured in their own jargon.....I found it interesting they are trying to make as unused industry phrase 'progressive compression technology', into their own seemingly proprietary feature when in reality it is just the way scroll compressors (used by many) work..I will make an attempt to compare some other units including this in the next couple weeks.
@@WorkingOnExploring awesome looking forward to the video. give Chris at cruise n comfort a call. I am very curious in its efficiency. Also it’ll be cool if you can post the excel sheet on google doc or something
I've been working on adding 5 new models to my analysis, including CNC's HD-12L....What I've been able to divine from what is on their website is indeed indicative of a high efficiency claim. At this point I am dubious however and am attempting to get more information from them. It appears they are using a single speed compressor (motor type unknown) likely using a thermostatic expansion valve and definitely using R134a, none of which are likely to produce a system that would stand an ASHRAE test and meet their claims. They are in a market space where they also don't have to prove any of their efficiency claims or produce data based on ASHRAE standard tests. Because I have worked in the custom A/C manufacturing business, I have a decent feel for what makes highly efficient systems and they do not appear to be on that path. I will give them the benefit of the doubt because it would be involved to do otherwise. If you are serious about a 12V system, take a look at the RecPro 12V rooftop system. It's a packaged roof unit made up of what may be almost exactly what CNC uses, has good performance numbers but is less than half the price.
I may get the information needed to finish my spreadsheet in a week or so and will publish it on workingonexploring.com/techdocs.
I know they have a 48v version of the HD-12L. At least that would yield more efficiency?
Possibly but if you want to go 48V checkout 'Hotspot's' 12kBTU minisplit (DC4812VRF I think is the part number). if you can accommodate that form factor (lots quieter and more efficient). Probably the most efficient unit made by anyone....at least I can accept their data as realistic...
I wonder if the Midea 8000 btu with compressor which is 15 seer would be a good choice . I have it in my Airstream and at 86 degrees in dry mode and sitting in front of a small fan I’m very comfortable. It should use much less in dry mode.
I scanned the Midea web site to attempt to identify the unit you were referring...there were several 8k's so I'll just make some general comments; 1} 8k is likely too small for the poor insulation inevitable in any commercial RV. 2) 15 SEER is most likely a 'single stage' (speed) unit which is on the low end of what is possible with A/C's commonly available. 3) By referring to 'DRY' mode, I assume you mean DEHUMIDIFY. Dehumidification mode will remove more water in humid air than 'normal' mode and also requires more power to do so BUT, in high humidity environments, normal mode will still expend a lot of energy removing 'latent' heat (condensing moisture) because it is an unavoidable step in coming humid air. 4) With air movement and virtually any air conditioner, you can be comfortable directly in front of it. Air conditioning design is about sizing to a space and condition to be able to cool the whole space so you're trying to achieve something different if that is all you want. 5) Midea builds air conditioners of many types and features which it sells under 17 wholely owned brands such as Pioneer, Senville, C&H, Mr. Cool, Gree etc. It might be safe to say that it's likely that brands that appear to be new are likely a Midea owned brand. Most brands have some minor feature changes and may sell nearly identical products with minor differences. For instance, some sell wifi enabled controls. Mr. Cool focuses on DIY installs (and are significantly more expensive). Most products are less expensive AND less capable than products from premium brands such as LG, Mitsubishi, Daikin, Toshiba, Panasonic, etc.
@@WorkingOnExploring Great info. Im talking about a window unit thats rates most efficient out there and has a compressor . Its used 30 percent less on dry mode so that means even less power. I like the fact that when it breaks its cheap enough to just get a new one rather that being at mercy of dishonest ac techs. Im buying a road-trek today and when the current ac breaks ill try it. Im also gonna test the power consumption of the one i have in my airstream which i keep on the highest setting 86 and its still feels great if i have a simple fan. I actually prefer it to the cool mode . Then maybe i can use less solar to run my ac if i choose to go solar in ny road-trek which would be my ultimate dream to boon-dock in Baja del Sur in summer. Ill let u know .
Window units are, without a doubt, the most economical solution. The largest drawback is noise. Take a look at the newest LG 9k that is a variable speed (inverter). It is more energy efficient than most other window units that are single speed. It is also quieter....around 50dBA rather than 60dBAs as most are.
@@WorkingOnExploring Yes i just installed the Lg dual inverter window ac in a rental. I love the idea of using new technology without being beholden to the experience repairs that usually accompanies this new tech. I got it on sale at costco for 300 and will probably last 5 years or more. I just put $2200 in simple repairs in my central ac and had to deal with dishonest techs . One took out freon the mext putting it back lin. In reality it just needed the coil cleaned which i did myself for 7 dollars. Never again !! Only window ac now that economical models .
I had a rental experience 2 years ago where 3 techs all gave me different failure analysis and the last one stole the refrigerant...I kicked them out, drove from WY to SoCal in a day and spent 2 weeks buying and installing 2 new systems...you should be equally wary and I'm glad you've found good solutions that meet your needs.