Air/Heat Pump Compressor not turning on

[greenfield3]

We have a 2019 Thor Aria 3901 and recently pulled into a camp site and the rear air/heat pump compressor will not engage. The fan works but no heat or cooling. I have verified we have 50 amp power. Has anyone else experienced this and if so, is there steps we should try? We called Thor and CW and have an appointment if no other options are available.

[jtyphoid]

Does your Firefly show "load shed"? Mine did and it was supposedly a problem with the current sensor in the PMM. The FireFly sheds the load if it thinks that the compressor is pulling too much current.

[Bob Denman]

What is your thermostat set at?
(Sorry to ask the obvious question...)

[greenfield3]

I am not seeing "SHED" the fan works as normal just the compressor does not engage. I have moved the thermostat from 60 to 75 with no impact.

[lwmcguire]

Originally Posted by Bob Denman

What is your thermostat set at?
(Sorry to ask the obvious question...)

Certainly the best place to start verifying

[jtyphoid]

Originally Posted by greenfield3

I am not seeing "SHED" the fan works as normal just the compressor does not engage. I have moved the thermostat from 60 to 75 with no impact.

Thinking back, I think that mine didn't actually start with the "load shed" message, but that's what it was doing by the time I got it in for service. I think that it started out like yours. Everything appeared to be normal, but the compressor wouldn't run.

Besides the current sensor, I think that the tech also found a bad driver board on the Firefly G6A panel.

[greenfield3]

Thanks all!

[Mulva]

Have you tried with the generator running? That will help isolate if you have shore power issues.

[Mulva]

Be sure to disconnect shore power while testing the generator as your power source.
As you should know, you can manipulate the FireFly System. Sometimes when I know I have 50 amp Service, FireFly will show 30amp on the panel. Make sure you adjust accordingly.

[Berlin Kid]

Same thing happened to me. Warranty service found that the relay was stuck. He tapped on the relay and ac started working. He replaced the relay and

[jtyphoid]

Originally Posted by Berlin Kid

Same thing happened to me. Warranty service found that the relay was stuck. He tapped on the relay and ac started working. He replaced the relay and

Do you know where the relay was (G6A, PMM, somewhere else)?

[Berlin Kid]

It was on the roof inside the ac shroud. It is the only relay there.

[cavie]

Originally Posted by Mulva

Have you tried with the generator running? That will help isolate if you have shore power issues.

the fan is running. He has power to the roof.

[terry.bird4@verizon.net]

I had similar concern with heat turning on in my 2020 Thor Four Winds C coach.
I turned on the propane tank and opened the valve and then turned the thermostat panel to heat with the fan on auto. It worked fine. I also noticed the heat continued to pour out of the floor vents even during the times the heat pump was only in the fan mode.
Give this a try and see what happens. Good luck!

[cavie]

Originally Posted by terry.bird4@verizon.net

I had similar concern with heat turning on in my 2020 Thor Four Winds C coach.
I turned on the propane tank and opened the valve and then turned the thermostat panel to heat with the fan on auto. It worked fine. I also noticed the heat continued to pour out of the floor vents even during the times the heat pump was only in the fan mode.
Give this a try and see what happens. Good luck!

Terry, you should change your user name. Email will get you junk mail. And lots of it.

[cavie]

Originally Posted by jtyphoid

Does your Firefly show "load shed"? Mine did and it was supposedly a problem with the current sensor in the PMM. The FireFly sheds the load if it thinks that the compressor is pulling too much current.

Fire fly will shed any designated load in order to keep the total RV load under 50 amps. It scenes the entire load going thru the main breaker not just the compressor. It cannot single out the fan and the compressor. It sheds the whole AC system or which ever other equipment it is set for.

[terry.bird4@verizon.net]

I have been thinking of changing my email address. I don't want my name showing any more. Verizon set it up this way years ago and I just went along with it. Thanks for your suggestion.

[cavie]

Originally Posted by terry.bird4@verizon.net

I have been thinking of changing my email address. I don't want my name showing any more. Verizon set it up this way years ago and I just went along with it. Thanks for your suggestion.

Don't have to change your email address. (But it would be a smart idea) just take it off this forum. Put a fictitious screen name in it's place. If you look at the forum 99% are fake names. Cavie is 1/2 of a last name.

[16ACE27]

Originally Posted by Mulva

Be sure to disconnect shore power while testing the generator as your power source.

Why? He has an Automatic Transfer Switch that will automatically switch to generator power (after the timed warm-up period) even if he is plugged into SP. Unless you think it will affect his troubleshooting procedure in some way?

[powerboatr]

my rear bedroom hp did this a in November
the end result was the heat pump switching valve , was stuck in the cold mode, had power and everything.
bottom line was replace the unit
because unsoldering in and resoldering a new switch valve was going to cost more than a new unit