Community Forums

cpd520 · 04-01-2020, 03:37 PM

Hi all, here's my issue. 2014 Phaeton MH.

Two roof AC's (Airxcel units). For a while I noticed rear unit ac and electric heat were hit and miss starting, very random. Initially it was so occasional that I thought I was imagining. Now it won't start on AC or electric heat. The fan still comes on when set to Fan Mode "on" position and propane heat comes on. The fan didn't bog or slow down when it did decided to work.

Physical inspection on roof didn't show any obvious issues.

It's getting warm here in Casa Grande, AZ. I need to troubleshoot this and get it fixed or call a repairman in.

Any AC guys on here to give me some diagnosing advice??

okcnewbie · 04-01-2020, 03:41 PM

If it's just the compressor that's not coming on than maybe it's the starting/run Cap. Often you can actually see a bulge in the capacitor when you do a visual inspection.

cpd520 · 04-01-2020, 03:47 PM

Quote:

Originally Posted by okcnewbie

If it's just the compressor that's not coming on than maybe it's the starting/run Cap. Often you can actually see a bulge in the capacitor when you do a visual inspection.

Thx okcnewbie. The fan does not come on when trying AC/electric heat. It does come on in fan only mode.

Would a bad start capacitor cause the fan not to come on if compressor doesn't come on?

okcnewbie · 04-01-2020, 03:55 PM

My experience has been that the fan still comes on even if the compressor doesn't come on. At least that's what I think I remember.
When you say electric do you mean heating element? If it's a heating element than I would start to think it's the thermostat.

Do you have two thermostats or just one? I'm not familiar with MH's with more than one AC unit. If you can swap them and see if the problem moves than I'd do that.

Deep Water D · 04-01-2020, 04:13 PM

First thing to do is reset the thermostat. Google up the thermostat instructions for the procedure. It's different than simply pulling the thermostat fuse, although you might try that as well. Sometimes that works.

RonaldNC · 04-01-2020, 05:20 PM

I had the same problem with my Carrier unit (which may or may not be same as your's). It was the start/run capacitor, which came out being a dual capacitor that also operates the fan. You can google the procedure for testing the capacitor... not too tough to do. Replacing was also easy, once I found the capacitor.

Ron

mchero · 04-01-2020, 05:45 PM

What model thermostat? I assume you have a zone 1 (front) zone 2 (rear) ?

OP has AC/ heat pumps

cpd520 · 04-02-2020, 07:28 PM

Quote:

Originally Posted by mchero

What model thermostat? I assume you have a zone 1 (front) zone 2 (rear) ?

OP has AC/ heat pumps

Yep, 2 thermostats. Thet are marked RVComfort.HP

cpd520 · 04-02-2020, 07:30 PM

I will try flopping the thermostats tomorrow.

Xmcdog · 04-02-2020, 07:49 PM

Shopping the stats is a good start.

Capacitors are cheap, easy to check. Usually they work or not and as stated a bulge is the physical sign it is toast. If there is any oil on it then use gloves and place it in a plastic bag. The older ones used a PCB laced oil. Dispose of it in an appropriate manner.

In addition to the start/run capacitor there will usually be a starting relay.
Depending on the type of compressor. Intermittent compressor starting is usually the relay. Change all three components. Including the overload. They are cheap.

Please turn the power off before you start. Remember the left had rule!
Work safe.

Ray,IN · 04-02-2020, 10:18 PM

Quote:

Originally Posted by Xmcdog

Shopping the stats is a good start.

Capacitors are cheap, easy to check. Usually they work or not and as stated a bulge is the physical sign it is toast. If there is any oil on it then use gloves and place it in a plastic bag. The older ones used a PCB laced oil. Dispose of it in an appropriate manner.

In addition to the start/run capacitor there will usually be a starting relay.
Depending on the type of compressor. Intermittent compressor starting is usually the relay. Change all three components. Including the overload. They are cheap.

Please turn the power off before you start. Remember the left had rule!
Work safe.

Changing a cap can be a shocking experience if you don't use a screwdriver to short between terminals first.