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Automatic Transfer Switch problem

Alraz24
Explorer
Explorer
My Ac will not run off generator. It runs fine off shore power. When trying to run off generator the AC will try to come on and then shut down to only fan working. Generator will still run, but produce no power and AC fan will run, but no compressor(just warm air)then later it will produce 120 volts again but, no ac compressor. Thought it might be automatic transfer switch so I wired a female plug end to the out put of the generator and plugged my shore power line in to it. AC and generator all runs fine. Do I need a new transfer switch?

Thanks

Mike
9 REPLIES 9

opnspaces
Navigator II
Navigator II
It kind of sounds like a ATS problem. But I would try hooking the generator back up to the the ATS and check again. When the AC stops cooling don't turn anything off. Leave the AC on and the generator running. Flip both generator circuit breakers off. Make sure they are fully off, you might have to push extra hard in the off direction on one or both of the breakers. Then flip the breakers back on and see if the AC comes back on.
.
2001 Suburban 4x4. 6.0L, 4.10 3/4 ton **** 2005 Jayco Jay Flight 27BH **** 1986 Coleman Columbia Popup

3_tons
Explorer III
Explorer III
Alraz24 wrote:
My Ac will not run off generator. It runs fine off shore power. When trying to run off generator the AC will try to come on and then shut down to only fan working. Generator will still run, but produce no power and AC fan will run, but no compressor(just warm air)then later it will produce 120 volts again but, no ac compressor. Thought it might be automatic transfer switch so I wired a female plug end to the out put of the generator and plugged my shore power line in to it. AC and generator all runs fine. Do I need a new transfer switch?

Thanks

Mike


If you have a pass-thru type inverter, it may be (as it’s designed) disqualifying the generator power (seeing the generator source as substandard), but only when the heavier load compressor attempts to start, this while the air conditioner fan remains operable…

3 tons -

MrWizard
Moderator
Moderator
You have a 30amp rv,
But what is the wattage rating of the generator, make and model # would be helpful, if its over 4000w, and built in, it has (2) circuit breakers on the generator and is wired to the second lesser rsted 20 smp breaker, you are bypassing that breaker snd powering everything from the breaker meant for just the appliances and outlets
Just because you can't see it, doesn't mean it isn't tripped,you should manually reset both breakers that are on the generator, posting make model and year of the RV might help, someone will know if there is switch you missed, hidden in a closet, or under a cabinet, maybe in the bedroom,
I once had a Komfort Brand motorhome with a switch in the bedroom Closet to change the a/c from shore power to generator power
I can explain it to you.
But I Can Not understand it for you !

....

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1997 F53 Bounder 36s

Alraz24
Explorer
Explorer
wa8yxm
It is a 30 amp. Can't see where it has tripped any breakers. When the ac wont run on generator when going through the transfer switch and then I plug it into the plug I wired to the generator out put and did nothing else, such as reset any breakers, it would seem to eliminate any breaker problem.

wa8yxm
Explorer III
Explorer III
30 or 50 amp RV
On a 30 the generator often has TWO circuit breakers one 20 amp one 30 amp

The 20 is for the AC and nothing else.
Home was where I park it. but alas the.
2005 Damon Intruder 377 Alas declared a total loss
after a semi "nicked" it. Still have the radios
Kenwood TS-2000, ICOM ID-5100, ID-51A+2, ID-880 REF030C most times

Bobbo
Explorer II
Explorer II
Alraz24 wrote:
Generator will still run, but produce no power

This statement is saying that the air conditioner has tripped the generator's breaker by drawing too much current. You have too much air conditioner and not enough generator. Adding an Easy Start to the air conditioner MAY help. Then again, it may not, depending on the size of the air conditioner and the size of the generator. My Honda EU2000i generator runs my 13,500 btu air conditioner with Easy Start installed near sea level just fine, but at altitude, it still fails.
Bobbo and Lin
2017 F-150 XLT 4x4 SuperCab w/Max Tow Package 3.5l EcoBoost V6
2017 Airstream Flying Cloud 23FB

arhayes
Explorer
Explorer
The breakers was also my first thought, but since you bypassed the AT switch and it worked, that’s probably not it. I’m assuming your Genny puts out 44amps and you’re not exceeding capacity? Mine will only run 2 of my 3 AC’s. If you’re comfortable digging into the ATS, you can cut off power and look at the Genny side solenoids to make sure the contacts are clean. Barring that, it’ll need replacement. I had to replace mine 2 yrs ago (rig was 6 yrs old) got the same one installed in my rig off Amazon. Pretty straightforward replacement.
Alan and Kathleen
2015 Grand Design Momentum 380TH (RVD2)
2014 F350 6.7L Diesel DRW (Stormtrooper)
2012 Honda Goldwing NAVI/ABS (Land Speeder)

Y-Guy
Moderator
Moderator
Which generator do you have? Just checking to see if you have you checked that both breakers on in the ON position no your generator?


Two Wire Fox Terriers; Sarge & Sully

2007 Winnebago Sightseer 35J

2020 Jeep Gladiator Rubicon

CA_Traveler
Explorer III
Explorer III
Open the ATS and check for burnt contacts, wiring etc. To be really sure wire nut the gen wires to the CB panel wires at the ATS and check the A/C.
2009 Holiday Rambler 42' Scepter with ISL 400 Cummins
750 Watts Solar Morningstar MPPT 60 Controller
2014 Grand Cherokee Overland

Bob