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Topic: Roof air mystery (Read 547 times) previous topic - next topic

Roof air mystery

For the first time the front air stops running the compressor when both airs are on. It runs fine by itself but the compressor shuts down when the rear is added. This appears to be generator related as both have worked on shore power since we left home. The two legs show 119 and 120 at the display. I switched the order and it always the front that drops out when both are on. It will cool for about 2 minutes after it is started while the rear is on before dropping the compressor. I have thought about adjusting the regulator up to 125 to see if it helps but checking here to see if it has happened to anyone else before
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Roof air mystery

Reply #1 –
Chuck,

Check the compressor side of the run capacitor if your unit is equipped with a double run capacitor. That is one side for the fan the other side for the compressor.  Seems like it is a 25/10 uf with the 25 side for the compressor. Sounds like the start capacitor is functioning.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Roof air mystery

Reply #2 –
After hunting around I found this. It should be what you are looking for or close to it. It/they (start & run capacitors) are located behind a removable cover passengers side after you remove the outside cover.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Roof air mystery

Reply #3 –
Thanks Mike,
 If I am going to throw parts at this that would be the first to try.

1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Roof air mystery

Reply #4 –
There is no need to spend the extra $ for a roof A/C specific capacitor.  A standard double run capacitor can be bought for ~$8-10 at most any HVAC store.  As another option you can get 2 singles and wire them in also as there is enough room for this option also.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Roof air mystery

Reply #5 –
Thanks Mike, I knew that the capacitor was not rv specific. I am in Redmond Or. and not much luck on local supply houses and HD and Lowes don't carry it. Back at home Johnstone Supply, that I have an account with is where I usually buy A/C components. This is not a trip breaker as one air will work until I get somewhere where the capacitor is available. Amazon has it but delivery is the problem.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Roof air mystery

Reply #6 –
Old trick I learned long ago. Replace capacitors every ten years. Prevents service calls to replace them.
I just loaned out my replacement sent to a neighbor and got replacements yesterday. Definitely time to change for me.
Scott
https://www.supplyhouse.com/Hartland-Controls-CAP-20-10-440R-20-10-MFD-Round-Dual-Motor-Run-Capacitor-370-440V
https://www.supplyhouse.com/MARS-11963-108-130-MFD-Round-Start-Capacitor-330V
$4.70 each

Re: Roof air mystery

Reply #7 –
I'll pick up some spares at home. Have an oval replacement going to the stop after next in La Grande Or.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Roof air mystery

Reply #8 –
Would this capacitor, not functioning properly, cause the blower motor to shut off prematurely?  My front A/C blower motor continues to run for several minutes after the compressor shuts off, the rear unit blower motor just recently started to shut down at the same time the compressor shuts down... ::)  ::)
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Gerry & Brenda
CHARLOTTE HARBOR, FL
1994 Grand Villa - # 4466
U300 Unihome - 6V92 Detroit
4 speed Allison - Jake Brake

Re: Roof air mystery

Reply #9 –
Quote from: dsd –
Old trick I learned long ago. Replace capacitors every ten years. Prevents service calls to replace them.
I just loaned out my replacement sent to a neighbor and got replacements yesterday. Definitely time to change for me.
Scott
https://www.supplyhouse.com/Hartland-Controls-CAP-20-10-440R-20-10-MFD-Round-Dual-Motor-Run-Capacitor-370-440V
https://www.supplyhouse.com/MARS-11963-108-130-MFD-Round-Start-Capacitor-330V
$4.70 each


Thanks for the links and suggestions. I have a pro account with supply house so I just ordered up some spares! Now I won't ever have any issues with my air 😂