Basement heat pump not providing heat 2003 Ultimate Advantage

[jeb-WO]

We have an '03 Ultimate Advantage. Owned basically since new. We do not live in it, and I do all the maintenance I can on it. It is well maintained, IMO, and has been a good rig for us.

Basement HVAC has been working well since new. But it no longer produces heat. I've read that the #2 compressor must run for the heat function to work, and both do run. You can hear the small pause/restart when the 2nd one kicks in in AC mode, and the amp draw jumps to 25-26. It's not a huge bother since both the LP heaters work well, but I would like to get this fixed if it's something that does not require an R&R. So any pointers appreciated.

 

[Shade Tree-WO]

Jeb, I have done some repair on my Coleman basement unit in my 2004 Itasca Horizon and compared the amps in a/c mode, replaced fans and motors. From what I understand your amp draw no matter the mode should not be more than 3-4 amp difference between compressors and maybe not as high as you described.

With all that said, I am no expert but have consulted with Steve SHELBURNE from SHELBURNE RV out of Cleveland TN on mine. He was very helpful and has numerous YouTube videos concerning the basement units. He is has added a shop in Florida recently. His contact is 423-290-8367, website is Shelburnerv.com with links to his YouTube videos.

Hope this helps!
Mike

 

[DancinCampers]

You can turn off the breaker to the #2 compressor and the #1 compressor should run in the electric heat mode. It is true that in the electric heat mode the basement PC board will activate both compressors. If using only the #1 compressor and the unit is not heating, I would suspect the reversing valve circuit.

 

[RayIN]

Try the easy thing first. Turn on the RVP unit in air conditioning mode and run for a short while, then turn off and immediately switch to heat pump mode. Sometimes the reversing valve gets stuck if not used for a long time. Then again it can be corroded electric connections on the reversing valve.

I assume you're on a 50A service, otherwise the Winnebago-specific EMS/energy management system will keep #2 compressor from operating on 30A service unless it has been disconnected.
If you are familiar with working with 120VAC, you can switch the wires in the relays for both compressors and swap #1 with #1 compressors without any issue.(wiring diagram on back of electrical panel door) Those 2 compressor relays are located in the top right of the electrical box. The top one is #1 from the factory, but it makes no difference in operation.
I assume you have downloaded the RVP basement unit service manual, it has an excellent troubleshooting section. The service manuals differ slightly so it's best to download the one for your model#.
BTW, what is your model#? I've overhauled mine and can address problems with the 6535 model best. You model# will be found on the sticker on the left end of the cabinet, hard to see since it's so close to the rear cap. I have to use a mirror and flashlight to read.
Your amp-draw is correct when both compressors are operating because all components are operating; both compressors, indoor fan, outdoor fan, and thermostat; all are connected to the electrical panel.