Dometic AC on Generator

[Jagspe]

Good Afternoon Everyone,

I came into a problem the last time I used my AC on the generator. The generator runs fine when the AC is off. That includes me using the microwave over. Moments after I turn the AC on, the generator stalls and turns off. I get a warning light that says that there is not enough power to run the AC. I don't have anything else running in the RV so I don't know how that would happen.

Any ideas?

[TURBS]

What size generator?

2500 watts is the very minimum 3000 + would be better.

What are you plugging into on your generator?

Your converter is always running, 2-8 amps


2015 Columbus 320RS
2008 2500HD Duramax
2015 nights camped "34"
2016 nights camped "10"

[Flybob]

Need more information, What is the unit? Is this an external generator or a built in? There are most likely other things running, converter, etc. What size / manufacturer generator?

[SeaDog]

Its best when stating a problem that you give some background ie: Type of rig, size of generator.

What it actually sounds to me is your AC is pulling more amps on startup then your generator can handle. Some folks myself included have added a hard start kit to the AC to assist in faster start with less amp pull so that the generator can handle the startup.

[SeaDog]

You guys are to fast for me there were no reply when I started typing my response

[Jagspe]

Sorry guys. I have a 2013 Sunseeker 3170 DS. I have a built in Onan RV 4000.

[Bama Rambler]

There have been a few reports lately of those gennys having problems running the A/C. I'm not sure what the outcome is, but do a little searching for the same problem and you may get some help with things to try.

[RubberNail]

I have a 2013 Sunseeker 2300. I have experienced problem with cold generator handling dometic frig, inverter and A/C when it cuts on, particularly at elevations above 5000 feet. Generally after it runs for a few minutes, handles load okay. BIGGEST problem with MH generators is running them enough that the carb don't clog up. Mine is running good now, but went through 3 days of boondocking with 24/7 running A/Cs, microwaves, coffee pots, etc - not all at the same time. Think that cleaned up the carb.

MH genny has worst of all worlds - ethanol in gasoline and usually low usage. Keep in mind that unit from factory may sit on lot for several months and you may have a problem before it's driven out of the lot.

[Threegaleh]

I have had the same problem and a guy who repairs small engines says it's not big enough to run the air. Your post could have been wrote by me it's so similar.

[KatanaPilot]

A 4000 watt generator should be able to handle a 15K BTU air conditioner. My 3200 watt diesel generator runs my Atwood 15K A/C without any issues.

The problem with the newer Dometics is that they may have eliminated the start capacitor - which greatly increases the starting load. So I would check for the presence of a start capacitor, check the run capacitor as well and add a hard start kit (which is a start capacitor) if one is not present.

[zuterbru]

I would try running the AC with everything else off. I would pop the breakers for everything but the main and AC. Let the generator run for a few minutes and try it then. The converter can take quite a bit of power if the batteries are low. Another thing I thought of, you might have a spark arrester on the muffler. Take that out and clean it, often. I had mine plug up on my portable, it would barely start it was so bad.

[ethacker]

I am having similar issues. I can run the front or back AC but not both. Also one of the 20 amp breakers tripped and will not reset. I have an appointment with the Cummins Dealer on 7/18.
2016 Georgetown 378XL with a 5500 Cummins gas genset with less than 30 hours.
Will post what I find out from the dealer.

Old Fart in Katy, TX

[Utah Traveler]

I have two yamaha ef2000 v2is inverter/generators paired. in SLC Utah at 4200' elevation I can only run my fridge and 1350Watt Coleman roof A/C.
If I dry camp (usually do)at 5600' to 6900' With fridge on propane and A/C on the A/C proves too much after about 35 seconds the gens cut producing power to protect itself and the appliance.
Yamaha service center says stock Carb. jet is designed for sea level to 4000 feet elevation. getting too much gas and not enough air. I need to install a high altitude kit that will have a jet that is two sizes smaller.
also a hard start capacitor on a
A/C unit would also help.

[aviator42]

I just tracked down the same problem. I didn't realize I had the Electric hot water switch on (it's outside).
Still should not have been a problem with my new Champion 3200 generator except I happen to be in an area where ethanol gas it quite popular. I did something unusual for me ... I read the gen. manual. It said not to use octane levels of gas below 85 or more than 10 percent ethanol. I used 87 and I don't know the content of ethanol but I must have had a reduced HP output. When I turned on the AC with hw engaged ... bingo ... killed the generator.
I turned off the 'outside' hw elec. switch got high octane gas and ran the generator and AC all night last night with no problems.

aviator42

[Jagspe]

Looks like fuel pump is ok. I am currently running the generator for a half an hour. Seeing if that will help prior to me turning on the AC.

[Jagspe]

Does anyone know if this can be an AC issue? If so is there a way to troubleshoot.

[lgray]

Originally Posted by Jagspe

Does anyone know if this can be an AC issue? If so is there a way to troubleshoot.

If the AC is running on shore power not likely the AC. Your 4000 Onan is more than enough to run a 15,000 BTU AC.
My brother has a 2013 Onan 5500 in his Toy Hauler, his issue was that it would run fine when running a load (AC), but would stall as soon as not under a load. He tried everything, including removal of the carburetor. He finally took it to an authorized repair shop.They replaced the carburetor and runs fine now.Per the shop not worth the cost to rebuild…shop also said they have recently seen some with similar issues.

[Jagspe]

I can run the microwave with no issue on the generator.

[lgray]

Originally Posted by Jagspe

I can run the microwave with no issue on the generator.

A 15,000 btu, AC takes between 3300-3500 at start and 1300-1800W to run.

[TURBS]

15k btu a/c takes closer to 2500 watts to start and about 1800 to run.


2015 Columbus 320RS
2008 2500HD Duramax
2015 nights camped "34"
2016 nights camped "14"