ok, help me fix my heat pumps

[1201]

If run at slower speed for a few hours the computer will speed up the compressor for about 10 minutes to recirculate the oil that got stuck in system distribution.

So that explains these spikes?

 

[1201]

Update. All my machines were about a lb low. I still suspect they were low from the factory because two of them had no detectable leaks after pressure testing, vacuum testing and bubble testing the lines
Maybe they have some internal leaks?

Any how I filled them up to spec and they've been working fine now since mid February. If it happens again I'm just going to add in refrigerant in .25lb increments

 

[1201]

@1201
Have you had any real cold since your repairs?
How is the system running?

Haven't had anything below freezing but it's gotten down to 33-35 since and they've worked well. Compared to my old house with electric resistance heat, these use almost no power

My total HVAC use for the last 30 days

 

[RCinFLA]

I left the coils vertical on one of mine. I’m curious your thoughts on how big a deal it is? What you say makes total sense, could kick myself…….

Depends how much line length you have coiled up. Pull-it-out-of-ass estimate would be no more than 15-20 ft of line coiled up vertically.

 

[RCinFLA]

So that explains these spikes?

View attachment 203946

Likely so, good catch. You may scratch your head wondering why air vent gets colder every so often.

If in heat mode, you will have a similar spike in current draw when unit does defrosting which puts unit back in cooling mode to heat up outside coil to melt any ice build up.

 

[MajicDiver]

Depends how much line length you have coiled up. Pull-it-out-of-ass estimate would be no more than 15-20 ft of line coiled up vertically.

I used a single 18” loop on one of mine, that should be about 5 feet. My other is a vertical drop then horizontal sloping downward about 5 feet. Also have 2 mitchibushi mini splits installed professionally in the same time frame all about a year ago. It will be interesting over the years which ones croak first.

 

[MajicDiver]

So that explains these spikes?

View attachment 203946

All 4 of our mini splits go thru a defrost cycle periodically when ambient temperatures are below mid 30’s. The Mr Cool units throw a code on the LED status display when it does that. Our two Mitsubishi units seem to do the same thing but don’t have anything to tell you that. When this happens the power spikes for just 3/4 minutes.

 

[Quattrohead]

Did you install the units originally or someone else ?
Either case, could have lost some refrigerant during the install.

 

[1201]

All 4 of our mini splits go thru a defrost cycle periodically when ambient temperatures are below mid 30’s. The Mr Cool units throw a code on the LED status display when it does that. Our two Mitsubishi units seem to do the same thing but don’t have anything to tell you that. When this happens the power spikes for just 3/4 minutes.

That's a good point but I don't think that's the case here as I've always had these spikes, even in the summer

 

[1201]

Did you install the units originally or someone else ?
Either case, could have lost some refrigerant during the install.

I installed them myself but didn't lose any refrigerant during the install. I vacuumed the lines then opened the port. I really don't know why they were low but at least I'm glad it was just a case of low refrigerant