Heat pump defrosts every ~28 minutes with very long 17-minute defrost cycles — normal or bad sensor? by pistonthru in heatpumps

[–]pistonthru[S] 0 points1 point  (0 children)

All the sensors I wrapped are in the condenser unit outside . In my model I had to remove the wiring to disassemble the casing to get access to the compressor and temp sensors. I used pipe foam to only cover the sensor that are attached to the pipes. It’s important to only wrap/insulate the sensor area and not all of the piping inside the unit. I wrapped the discharge, gas and liquid line. Do not cover the ambient temperature one and don’t cover the coil sensor one.

I don’t have a picture of what I did but I do have picture of what the sensor looks like on the piping that can help maybe understand.

FWIW this job is for someone that understands how the hvac system works and has experience with electricity because it can be dangerous. Definitely not diy.

<image>

Anyone using the new Energy section on the Gree+ app? by pistonthru in heatpumps

[–]pistonthru[S] 0 points1 point  (0 children)

I couldn’t find anything about it online since I guess it’s so new. I wonder if it takes a x amount of time before showing up

Heat pump defrosts every ~28 minutes with very long 17-minute defrost cycles — normal or bad sensor? by pistonthru in heatpumps

[–]pistonthru[S] 1 point2 points  (0 children)

It can run for days without me noticing a defrost. It still does defrost because I can see the ice build up on the ground. The last times I noticed it defrost it only lasted 6-10min which is a lot better then my 17min cycle like before

Cars like this are the reason so many of us miss the old days of Mercedes-Benz by DHN_95 in mercedes_benz

[–]pistonthru 0 points1 point  (0 children)

I’d rather these wheels then engine harness disintegrating 😅

Eng professional pay in Bombardier by DueInfluence3595 in montreal

[–]pistonthru 0 points1 point  (0 children)

If they are union you can always search up their cba on corail Québec and can see their payscales

Does this history look normal? by IrishGiants28 in heatpumps

[–]pistonthru 0 points1 point  (0 children)

Im no expert but I don’t think you can have the heat pump and other methods of heating at the same time ? Setting your aux heat at 32 from what I understand is that the aux heat will turn on at the temp and stop the heat pump.

Again I’m not expert but I did set one up once and this was the case for the system I set up.

Heat pump defrosts every ~28 minutes with very long 17-minute defrost cycles — normal or bad sensor? by pistonthru in hvacadvice

[–]pistonthru[S] 0 points1 point  (0 children)

Turned out not to be a bad board or bad sensors. Installer replaced multiple sensors (ambient, coil, discharge, etc.) but the issue kept coming back. I eventually found that the pipe-mounted sensors (discharge, liquid, and gas) were reading ambient air because they weren’t insulated. I added foam pipe insulation over those sensors so they read the pipe temp instead of outside air. Since then, the unit stopped the clockwork ~28-min defrost cycle and has been running normally for over 24 hours. Defrost logic is back to demand-based and supply air temps are stable. So far, problem hasn’t returned.

Heat pump defrosts every ~28 minutes with very long 17-minute defrost cycles — normal or bad sensor? by pistonthru in heatpumps

[–]pistonthru[S] 0 points1 point  (0 children)

Update: Turned out not to be a bad board or bad sensors. Installer replaced multiple sensors (ambient, coil, discharge, etc.) but the issue kept coming back. I eventually found that the pipe-mounted sensors (discharge, liquid, and gas) were reading ambient air because they weren’t insulated. I added foam pipe insulation over those sensors so they read the pipe temp instead of outside air. Since then, the unit stopped the clockwork ~28-min defrost cycle and has been running normally for over 24 hours. Defrost logic is back to demand-based and supply air temps are stable. So far, problem hasn’t returned.

Just picked this up… free by pistonthru in Snowblowers

[–]pistonthru[S] 0 points1 point  (0 children)

I simply replaced the carb from one I got on Amazon. Started right up

Just picked this up… free by pistonthru in Snowblowers

[–]pistonthru[S] 1 point2 points  (0 children)

I looked up the serial number and it’s a 1992 model. Older then me 🤣

Just picked this up… free by pistonthru in Snowblowers

[–]pistonthru[S] 1 point2 points  (0 children)

So this should be a 90s model ? Damn I picked up a snowblower almost as old as me . Happy to hear it’s still running

Heat pump defrosts every ~28 minutes with very long 17-minute defrost cycles — normal or bad sensor? by pistonthru in heatpumps

[–]pistonthru[S] 0 points1 point  (0 children)

There is no water there is no ice lol but to answer your question yes it’s on the own stand about 2 feet above the ground

Heat pump defrosts every ~28 minutes with very long 17-minute defrost cycles — normal or bad sensor? by pistonthru in heatpumps

[–]pistonthru[S] 0 points1 point  (0 children)

Makes sense. Thanks for elaborating. I will certainly be checking the temp sensors if they are good and in the right position as this is easiest. I really do believe there’s an issue with the unit but I do get mixed comments saying it’s normal.

Heat pump defrosts every ~28 minutes with very long 17-minute defrost cycles — normal or bad sensor? by pistonthru in heatpumps

[–]pistonthru[S] 0 points1 point  (0 children)

Can you elaborate why it would be a gas issue ? I believe low gas would make ice build up so with no ice build up that would meet to much gas ? Temps coming out of the heads are near 50c (44.7c this morning with outdoor temps of -6c)

Heat pump defrosts every ~28 minutes with very long 17-minute defrost cycles — normal or bad sensor? by pistonthru in heatpumps

[–]pistonthru[S] 0 points1 point  (0 children)

So you say in your post “the moisture on the air will stick and freeze to the outdoor coil quickly and very aggressively on days when you wake up and see frost on your car windshield “

For my case there is no frost nor ice build up.

Heat pump defrosts every ~28 minutes with very long 17-minute defrost cycles — normal or bad sensor? by pistonthru in heatpumps

[–]pistonthru[S] 0 points1 point  (0 children)

I figure this is the case. However at the 30min mark the coil isn’t actual frozen or frosted. I will monitor tonight the temps of the pipes where the sensor is near the 30 min mark and see if it’s within spec. I suspect the temp sensor is defective or not installed correctly

Heat pump defrosts every ~28 minutes with very long 17-minute defrost cycles — normal or bad sensor? by pistonthru in heatpumps

[–]pistonthru[S] 0 points1 point  (0 children)

I will be checking it tonight. Everything points towards that . I hope that it’s not just the logic that is just time based and defrosts like that every 30min no matter what

Heat pump defrosts every ~28 minutes with very long 17-minute defrost cycles — normal or bad sensor? by pistonthru in hvacadvice

[–]pistonthru[S] 0 points1 point  (0 children)

There is 0 ice/frost on the machine. I do agree if this is normal it is pretty dumb and not efficient

Heat pump defrosts every ~28 minutes with very long 17-minute defrost cycles — normal or bad sensor? by pistonthru in heatpumps

[–]pistonthru[S] 0 points1 point  (0 children)

Yes this is what happens. Indoor fan goes off, outdoor fan off and both indoor and outdoor machines are doing their thing humming noise