Heat Pump Issue

[AllDodge]

Have a house which has not been lived in for about 3 years. Has a Rheem 2.5 ton 13 seer system installed in 2006. Turned power ON, then turn unit to heat. Inside blower started running but smelled the electric coils. Check the outside unit an it was not running.

Turn thermostat to cool, and outside unit turn on and air was cool. So the out side unit is not turning on during heat mode. The thermostat turns on a light for AUX when going for heat

 

[Done That]

Picture or description of thermostat and its wiring would help. Someone may not have installed a heat pump thermostat. Outdoor unit needs a Y call plus B for a Rheem unit to run in heat mode, Y turns on compressor and B shifts the Reversing valve.

Have you lived in this house with the unit working in heat pump mode or is this a new home to you?

AUX would normally be wired to E or W terminal of the tstat. Just checking, are you 100% certain OD unit is a HP?? Model #?

 

[Milton Shaw]

May be operating properly. On most heat pumps if the thermostat is turned up more than 2 degrees it goes to aux heat strips until the 2 degree mark and then switches to heat pump. That's how most are designed. That is why it does not save money to turn heat pumps down at night, the recovery is all heat strips that use 3 times the watts than when in heat pump operation...

 

[AllDodge]

Have to agree with the 2 degrees.
I have had heat pumps for many years and what you said is accurate, only issue is all of them (so far Janatrol, Rheem and now Goodman) the outside unit continues to run even when the heat coils are turned on.

I did shut it down, go to cool and verified outside unit turned on. Then turned to heat and increased call as only 1 degree and it still would not turn on, only the AUX light turned on and the inside unit

 

[Done That]

Some universal tstats have to be configured thru the menu for system type, again, that may not have been done properly.

Running Emergency heat would only bring on strips. As you said, in normal pump mode strips would cycle in the background with the OD unit running with a large differential.

Still wonder if this is a new to you unit or if its verified to have run properly as a pump in the past?

 

[AllDodge]

It is a new to me unit, but know the guy who built the house and was sold due to bankruptcy. The house was in good shape with no damage on the way out. The stat is not programmable its a simple Protech model. Wonder if the reversing valve hangs will the unit still power up?

Guess it could be that the stat has the issue

 

[MagKarl]

Are you sure it's a heat pump and not just A/C?

 

[AllDodge]

Are you sure it's a heat pump and not just A/C?

Yes it is a heat pump. Model RPNE-030JAZ and found online as a 2.5 ton HP

Talked to my friend that runs his own HVAC shop and I'm going back over to the house to check some voltages

 

[Done That]

You should be able to take a meter outside and confirm if Y is getting 24V with a call for compressor heat. The B terminal should also be seeing 24V to energize the RV in heating. You are obviously getting 24V on Y with a cooling call if the OD unit is running.

FYI the D terminal on the heatpump board is for the backup heat connection to ID unit for defrost, then you also have R for power and C common.

Depending on the model the Rheem defrost board may have two red LED's for troubleshooting. There is also a two pin test header you can short with a screw driver to force a defrost, but this typically requires it to be below about 32F outside.

I'd pull the tstat off the wall and verify wiring, then do same at OD unit. Tstat wiring at OD unit can also get damaged by weedwackers, mice chewing thru etc. Need to work thru a few simple checks to narrow down the possibilities.

 

[AllDodge]

Well this was wired up by the local guy, and I'll just say jack leg. He installed my last one and I fixed some of his issues. He ran romex thru the vent because he didn't want to go get some more flex conduit.

In any case he used 2 each 3 conductor cables going from stat to ID and 2 others going from ID to OD. If I don't get it figured out my friend plans to come down this Friday to fix it

 

[Falcon67]

Agree on the 2 degree - the Honeywell stat on our Ruud heat pump turns on Aux heat anytime the temp differential between ambient and setting is more than 2 degrees. We shorted up our setbacks to avoid it. Another reason we will be ditching the Honeywell for a Ecobee - the Ecobee has settings to avoid such issues. As I recall, you can even disable emergency heat on the Ecobee.

 

[AllDodge]

It either got confused or just doing the way I did it, made it happen. Right now its appears to be working. I did go and hand twist all the wire nuts and buttoned it ID unit back up.

Turned heat on, increase to one degree above where it was and heat came on without the AUX light. Outside the unit was running. Let it run until it shut it self off, which was 1 degree higher then I had it set.

Turned the stat down to 58 and will watch it for a day or so. If it continues to be OK I'll turn the water on and check for leaks

And thanks for the flashing led's. They do flash and according to the label everything is ok

 

[Done That]

The Rheem board has a built in short cycle delay timer, so if you turn it on and off rapidly you have to wait 3 minutes before it will start, just FYI. With normal operation the timer will expire during routine off time and it appears to start right up. Hope that makes sense, and just an FYI. The lights on the outdoor board will blink indicating it's in a delay.