This heat pump uses a time temperature controlled defrost so the video pertains to troubleshooting that particular type of control and not a Demand Defrost System that utilizes an outdoor ambient temperature sensor along with a coil temperature sensor. This video will hopefully help out the new guys or anyone interested in trying to troubleshoot whether the failure is related to the defrost board or the defrost thermostat. If I have to replace a defrost board I will always replace the defrost thermostat as well. This one ended up being a failed defrost thermostat and the defrost board tested out fine, so it was left in place. If the defrost board would have been bad, then the unit would not have shifted into defrost after shorting the speed up pin for 5-7 seconds and removing my screwdriver from it. The refrigerant charge seemed ok as well and was not the cause of this particular failure even though the system needed a new air filter and the filter grille cleaned badly. If you would like to know how to troubleshoot a demand defrost heat pump click the link below and be sure to check out my pinned comment in that video as well for a more detailed explanation. You can identify a demand defrost heat pump by looking for an Outdoor Ambient Temperature Sensor as well as an Outdoor Coil Temperature Sensor instead of a Defrost Thermostat. Stay safe out there, best wishes, and thanks for watching. ruclips.net/video/KPkLngDBLks/видео.htmlsi=cGSdyxcCj45IN_UP
Yeah, I know the cap comes off. The metal part of the probe was too fat. The ones I am using are my fattest set because they are more durable. I have a thinner set in my bag and micro probes in my van. Thanks for watching and for leaving a comment.
Geez! Brutal. We are supposed to get -5 to -10 wind chills tonight. Not actual temp though. We will be in the single digits tonight as the actual temp.
Not always, but I am always learning out in the field and online trying to keep up with all the changes in the industry. Pretty familiar with these types of units though. Worked with lots of them over the years and used to install Comfortmaker, Tempstar, ArcoAire, Payne, and Carrier units years back for equipment change outs.
During defrost the outdoor fan should turn off. Remember that the outdoor coil goes from the evaporator coil in heat mode (absorbs heat & moves it to the indoor coil via the refrigerant lines) and turns into the condenser coil (which gives up heat to the outside). In order for the coil to give up heat/build pressure the outdoor fan should not be running. Basically, when the outdoor unit goes into defrost, the mode is switching. Heat mode/evap coil outside to cool mode/condenser coil outside. The indoor blower should be running during defrost unless you have some fancy inverter horizontal discharge unit like a mini split. Some of those will turn the indoor blower off during defrost because they don't use strip heat. The outdoor defrost board will send 24 volts during a defrost on the W/aux/w2 or some other similar terminal to the indoor unit to turn on the heat strips during a defrost cycle. Whether you feel heat inside or room temperature air will depend on your heat kit size and whether or not your thermostat has the heat strips locked out based on a certain outdoor temperature. Remember during a defrost the indoor coil goes from the hot coil (condenser coil that gives up heat to the inside of your home) back to the evaporator coil (cold coil that absorbs heat from inside your home and moves it to the outside via the refrigerant lines). If your heat kit is sized appropriately you will wash out the cold air from being felt or you will still have a heat gain inside the home. If the heat kit is undersized, or maybe your heat strips aren't turning on because of a failure somewhere or like I said they are locked out on the thermostat, you will feel cool air blowing during a defrost inside your home. Look at the heat kit sizing. Lets say you have a 2 ton unit or 24,000 BTU heat pump. Remember there is 12,000 BTU per ton. Your heat kit is 8kw or 8,000 watts. Perform this calculation. 3.41 x 8,000 = 27,280 BTU. So, in this scenario if your heat strips are 27,280 BTU and your heat pump is 24,000 BTU inside during a defrost the air will only feel slightly warmer than room temperature air. Like the fan is running with fan on and no call for heat. Kind of washes itself out, but you are still getting a little heat gain of 3,280 BTU. Lets say you have a 2 ton heat pump again, but you are using a 10kw heat kit. Perform that same calculation. 3.41 x 10,000 = 34,100 BTU. In this scenario your heat strips would be producing 10,100 BTU more than your heat pump during a defrost so you would feel noticeably more heat during a defrost cycle when the indoor coil becomes the cold coil during the defrost cycle. Lets say you only have a 5kw heat kit on a 2 ton heat pump. 3.41 x 5,000 = 17,050 BTU. In this scenario you would feel some colder than room temperature air during a defrost cycle because the heat kit lacks the BTU equivalent to your heat pump by 6,950 BTU. I hope this helps you out.
Mine has frozen over a few times, usually around 4am, but by the time I get a chance to work on it the ice is gone from being turned off. What's a good way to test the defrost switch when's it's not frozen over? It's never tried to go into defrost and I'm not sure if it's the board, sensor or other.
Just make sure you are dealing with a time temperature controlled defrost and not a demand defrost system. Demand defrost uses a outdoor ambient temperature sensor in combination with an outdoor coil temperature sensor. If you have a time temperature controlled defrost system you can put the metal part of the defrost thermostat on some ice and use a meter after a minute or so to confirm it is closing. The close point of the defrost thermostat should be listed on it. For example the one here was a 65-33. Open at 65 and close at 33. Some won't close until 28 so they would need to be even colder. You can turn your system off and pull the defrost thermostat to then test it in the freezer inside your home. Typical fridge/freezers combos run a freezer temperature around 0 degrees, so they are more than cold enough to make a defrost thermostat close within a couple of minutes. Luckily I had snow in the video to use. Frost is normal on a coil, ice is not.
What I’ve done with those low hanging defrost switches is put a drip leg in the wires at the switch with a zap strap so that water does not run down the line and freeze the switch open.
Should be a waterproof sensor being that it is exposed to the elements, but it is a great idea as an added layer of protection against poor manufacturing. Thanks for watching & thanks for the comment. Stay safe out there.
@ I don't keep up with the bags, so I am not sure. Didn't know there was a smaller one available. I believe mine is the bigger one. The bag is heavy even when its empty. I think its like 9 lbs empty. Something like that.
Nice repair jake as I have said Ted cook seems to get the butcher sabotage jobs charies gets the second opinion scammer ones. Curtis gets the lazy lack of maintanace ones you seem to get the lack of maintanace ones and lazy install ones but lack of proper ductwork return sizing ones. As you mentioned some of the return ductwork is not sized properly more people when selling sytems should be checking the ductwork and sizing for the space. And making sure static pressures and cfm is adaquite. Again good work jake.
New Subscriber here Great tutorial on testing defrost T/S & Board on a frozen HP also its a good one & simple to Follow along & if you don't mind > Ill diff Share to a couple my new Techs & iam sure they will subscribe also Thanks & cant wait to see more of ur Content Thanks Again ....Keep on HVAC in
I have some. I have the tiny micro leads and a set of leads that are thinner than what I have on now. I keep my micro leads on my van because they bend up in my bag though.
This heat pump uses a time temperature controlled defrost so the video pertains to troubleshooting that particular type of control and not a Demand Defrost System that utilizes an outdoor ambient temperature sensor along with a coil temperature sensor. This video will hopefully help out the new guys or anyone interested in trying to troubleshoot whether the failure is related to the defrost board or the defrost thermostat. If I have to replace a defrost board I will always replace the defrost thermostat as well. This one ended up being a failed defrost thermostat and the defrost board tested out fine, so it was left in place. If the defrost board would have been bad, then the unit would not have shifted into defrost after shorting the speed up pin for 5-7 seconds and removing my screwdriver from it. The refrigerant charge seemed ok as well and was not the cause of this particular failure even though the system needed a new air filter and the filter grille cleaned badly.
If you would like to know how to troubleshoot a demand defrost heat pump click the link below and be sure to check out my pinned comment in that video as well for a more detailed explanation. You can identify a demand defrost heat pump by looking for an Outdoor Ambient Temperature Sensor as well as an Outdoor Coil Temperature Sensor instead of a Defrost Thermostat. Stay safe out there, best wishes, and thanks for watching.
ruclips.net/video/KPkLngDBLks/видео.htmlsi=cGSdyxcCj45IN_UP
Realy a very professional explanation of heatpump defrost cycle and related parts how they work. Keep the good work .
Thanks for tuning in.
Those probe tip caps come off. Nice vid.
Yeah, I know the cap comes off. The metal part of the probe was too fat. The ones I am using are my fattest set because they are more durable. I have a thinner set in my bag and micro probes in my van. Thanks for watching and for leaving a comment.
Good video. -10 windchill in the upper Midwest today. Stay warm.
Geez! Brutal. We are supposed to get -5 to -10 wind chills tonight. Not actual temp though. We will be in the single digits tonight as the actual temp.
Great job as always jake enjoyed the video very informative stay warm next week
Will try to. Getting ready to go on one now. 12 outside right now with -5 to -10 windchills.
Great video. You were extremely helpful. Great explanation
Glad it helped you out.
Nice troubleshooting & fix ... Nice vid as well ... Thx
Thanks man. Appreciate you tuning in.
Hi Jake you're obviously a wealth of knowledge as they say (Knowledge is Power)
Not always, but I am always learning out in the field and online trying to keep up with all the changes in the industry. Pretty familiar with these types of units though. Worked with lots of them over the years and used to install Comfortmaker, Tempstar, ArcoAire, Payne, and Carrier units years back for equipment change outs.
Great video very helpful
Thanks for watching and for leaving a comment. Appreciate it.
😮😊nice work 😊
Thanks for always leaving a comment. Appreciate the additional support.
Very good DF diagnosis. 😎👍
Stay safe out there over the next few days. Get warm when you need to.
Good stuff brother this helped me
Glad it helped you out. Thanks for taking the time to leave a comment.
Thanks for the video Jake.
Definitely. Appreciate the comment.
Great Job Jake !!!!!
Thanks for watching and for leaving a comment.
Nice job Jake.
Thanks for watching.
Nice job 👍
Thanks for taking a little extra time out of your day and leaving a comment. Appreciate that.
Awesome video
Appreciate you showing some support by leaving a comment. Thanks for watching.
Good Job!
Thanks for watching & for leaving a comment.
Great video. Just subscribed. Thanks.
Appreciate it.
Great video
Good to see a comment from you. Thanks for watching too.
Enjoyed the video good job = )
Thanks bud. Appreciate you commenting and showing some extra support.
Should the outdoor unit fan turn off in defrost mode? For some reason I was under the impression is should be running.
Also should the blower motor be running warm/hot when in defrost?
During defrost the outdoor fan should turn off. Remember that the outdoor coil goes from the evaporator coil in heat mode (absorbs heat & moves it to the indoor coil via the refrigerant lines) and turns into the condenser coil (which gives up heat to the outside). In order for the coil to give up heat/build pressure the outdoor fan should not be running. Basically, when the outdoor unit goes into defrost, the mode is switching. Heat mode/evap coil outside to cool mode/condenser coil outside.
The indoor blower should be running during defrost unless you have some fancy inverter horizontal discharge unit like a mini split. Some of those will turn the indoor blower off during defrost because they don't use strip heat. The outdoor defrost board will send 24 volts during a defrost on the W/aux/w2 or some other similar terminal to the indoor unit to turn on the heat strips during a defrost cycle.
Whether you feel heat inside or room temperature air will depend on your heat kit size and whether or not your thermostat has the heat strips locked out based on a certain outdoor temperature. Remember during a defrost the indoor coil goes from the hot coil (condenser coil that gives up heat to the inside of your home) back to the evaporator coil (cold coil that absorbs heat from inside your home and moves it to the outside via the refrigerant lines). If your heat kit is sized appropriately you will wash out the cold air from being felt or you will still have a heat gain inside the home. If the heat kit is undersized, or maybe your heat strips aren't turning on because of a failure somewhere or like I said they are locked out on the thermostat, you will feel cool air blowing during a defrost inside your home.
Look at the heat kit sizing. Lets say you have a 2 ton unit or 24,000 BTU heat pump. Remember there is 12,000 BTU per ton. Your heat kit is 8kw or 8,000 watts. Perform this calculation. 3.41 x 8,000 = 27,280 BTU. So, in this scenario if your heat strips are 27,280 BTU and your heat pump is 24,000 BTU inside during a defrost the air will only feel slightly warmer than room temperature air. Like the fan is running with fan on and no call for heat. Kind of washes itself out, but you are still getting a little heat gain of 3,280 BTU.
Lets say you have a 2 ton heat pump again, but you are using a 10kw heat kit. Perform that same calculation. 3.41 x 10,000 = 34,100 BTU. In this scenario your heat strips would be producing 10,100 BTU more than your heat pump during a defrost so you would feel noticeably more heat during a defrost cycle when the indoor coil becomes the cold coil during the defrost cycle.
Lets say you only have a 5kw heat kit on a 2 ton heat pump. 3.41 x 5,000 = 17,050 BTU. In this scenario you would feel some colder than room temperature air during a defrost cycle because the heat kit lacks the BTU equivalent to your heat pump by 6,950 BTU.
I hope this helps you out.
Mine has frozen over a few times, usually around 4am, but by the time I get a chance to work on it the ice is gone from being turned off. What's a good way to test the defrost switch when's it's not frozen over? It's never tried to go into defrost and I'm not sure if it's the board, sensor or other.
Just make sure you are dealing with a time temperature controlled defrost and not a demand defrost system. Demand defrost uses a outdoor ambient temperature sensor in combination with an outdoor coil temperature sensor. If you have a time temperature controlled defrost system you can put the metal part of the defrost thermostat on some ice and use a meter after a minute or so to confirm it is closing. The close point of the defrost thermostat should be listed on it. For example the one here was a 65-33. Open at 65 and close at 33. Some won't close until 28 so they would need to be even colder. You can turn your system off and pull the defrost thermostat to then test it in the freezer inside your home. Typical fridge/freezers combos run a freezer temperature around 0 degrees, so they are more than cold enough to make a defrost thermostat close within a couple of minutes. Luckily I had snow in the video to use. Frost is normal on a coil, ice is not.
Perfect
Thanks for watching. Appreciate you leaving a comment too. Luckily it wasn't the board.
What I’ve done with those low hanging defrost switches is put a drip leg in the wires at the switch with a zap strap so that water does not run down the line and freeze the switch open.
Should be a waterproof sensor being that it is exposed to the elements, but it is a great idea as an added layer of protection against poor manufacturing. Thanks for watching & thanks for the comment. Stay safe out there.
What kinda bag you there?
It is a veto black out edition backpack. Don't remember the model number.
I have that same bag. Veto blackout tec pac. Do you have the large one or smaller one ??
@ I don't keep up with the bags, so I am not sure. Didn't know there was a smaller one available. I believe mine is the bigger one. The bag is heavy even when its empty. I think its like 9 lbs empty. Something like that.
Nice repair jake as I have said Ted cook seems to get the butcher sabotage jobs charies gets the second opinion scammer ones.
Curtis gets the lazy lack of maintanace ones you seem to get the lack of maintanace ones and lazy install ones but lack of proper ductwork return sizing ones.
As you mentioned some of the return ductwork is not sized properly more people when selling sytems should be checking the ductwork and sizing for the space.
And making sure static pressures and cfm is adaquite.
Again good work jake.
Thanks for showing some support by watching & leaving a comment.
New Subscriber here Great tutorial on testing defrost T/S & Board on a frozen HP also its a good one & simple to Follow along & if you don't mind > Ill diff Share to a couple my new Techs & iam sure they will subscribe also
Thanks & cant wait to see more of ur Content Thanks Again ....Keep on HVAC in
That would be awesome if you share the channel with others. I definitely appreciate it.
A Mapp torch is a good way to defrost
Normally will use a water hose, but when it is real cold out I don't like using them. Thanks for watching & for leaving a comment.
Only problem with a torch, if your not careful you'll melt the aluminum fins. I use a heat gun on refrigeration evaporators.
You need to invest in micro leads.
I have some. I have the tiny micro leads and a set of leads that are thinner than what I have on now. I keep my micro leads on my van because they bend up in my bag though.
My micro leads are all bent to shit.
I ruined a pair before so I keep them in my van now. If I need them, I go out to the van and grab them.
Take a condensate vinyl tube about 3-4 inches and put the micro tips in both end keep them safe and you won’t get poked from your bag
@@keepnitkool9042 That is a great idea man. Thanks for the tip.
Great video
Thanks for watching and for leaving a comment.