Community Forums

Onrecess · 10-29-2020, 08:02 PM

I bought a 2003 Signature commander. The gen, is 12.5 kw.
When I was driving, the single AC (the middle, a 1300 the former owner had replaced) ran on inverter. T started the generator, and the gennie would die after 2 minutes. The original owner told me you can't run all 3 at once. I ran the single, and it ran fine, though I haven't had it running more than an hour yet. The other 2,1100s, rear and front ,(I think), ran (without the single) for about 20 minutes and the gen died. That's when I went to the single.
I can't believe my old 4400kw in my gasser ran 2 AC, but this monster can only run one.
Any ideas?

Ivylog · 10-29-2020, 08:26 PM

I can run three 15K on a 10KW generator. My educated guess is the fan belt is loose...needs replacing. You should be able to retrieve some codes.

Mr.Mark · 10-29-2020, 08:33 PM

I could run all three air units on my '08 Dynasty with the 10K genny.

With the current coach, I can run all four with my 20k genny

Safe travels,
Mark

twinboat · 10-29-2020, 08:34 PM

Have you had the fuel filters changed lately ?

A standard 50 amp RV park service is 12,000 watts, a tiny bit LESS then your generator. Your generator should run everything and then some in your RV.

Onrecess · 10-30-2020, 07:16 AM

Thanks, I'll look at the belt. If I need one, is it a standard belt from an auto parts or do I need to order one from??
As far as codes, It appeared to flash 1, I pushed down again, like my old gas one, thinking that brings up the actual code, but it just stopped flashing. So, I guess that is overtemp and likely the belt. I thought I wasn't getting the code. Someone said push down for 5 seconds to get codes, or 3 , depending on which post I read.

geordi · 10-30-2020, 02:27 PM

Fuel starvation is a real potential - the Onan fuel filter is comically small. I ended up building a "remote mount" for both my fuel and oil filters, now they are both spin-on filters mounted to the front wall and MUCH larger. If you choose to do this, the fuel filter (on my QD7500 at least) had a flared end on one of the connections to the filter. Cut that off and shove fuel hose over the copper and clamp in place. The other side on mine was flexible. Then just bring it out to the front wall and connect to a filter base. Don't forget to pre-fill the filter before installing it, I always use diesel-kleen in the silver bottle.

The belt.... IF it's like my QD7500, the fan is direct-drive but the water pump is NOT. That water pump is driven by the only belt, and needs to be replaced according to the maintenance schedule every 1000 hours. I will say that at 3k hours, the belt on mine was indistinguishable from the new one I installed, but getting to the thing was a fight b/c Onan in their intelligence didn't design an access door for it! Rather than remove the entire generator from the coach, I got creative with a grinder and made my own access door. Wouldn't suggest it unless you are comfortable with the tools, but it is an option.

Loren Rice · 10-31-2020, 12:06 PM

Another possibility is that the generator has a center tap. that's the neutral. so from neutral to either hot will be 120v. v Maybe you have two generators on one side of generator, overloading it. I don't know if they provide for running three AC's on a smaller generator. I could see perhaps running the front two especially while traveling or spending time in the main solon.
So a 10kw gen is really two 5ks. you can run 80% constantly of that with out shut down at sea level. so 80% of 5kw is about 33 amps . If you have two ac drawing 15 amps apeace and you turn on a micro wave or if you turn on anything else that happens to be on that side of the generator it will shut down. so that could be why it seems to be shutting down at different unpredictable times.
so look to see what else is on drawing power. An example would be, you can shut off one AC till food prep in micro is done, then back on with AC.

Ideally one generator, on each side of the generator windings to Keep it balanced load wise. If the micro wave isn't too big --- over 15 amps you should get by with no shut down, but if the tv is on, and you throw two 15 amp loads on might just hold on cooler day, but then someone turns one more thing on, like my battery charger draws a lot of current when battery's are a little low --- no way can a charger and two acs run at once.
Hope this helps
Loren

twinboat · 10-31-2020, 12:37 PM

Quote:

Originally Posted by Loren Rice

Another possibility is that the generator has a center tap. that's the neutral. so from neutral to either hot will be 120v. v Maybe you have two generators on one side of generator, overloading it. I don't know if they provide for running three AC's on a smaller generator. I could see perhaps running the front two especially while traveling or spending time in the main solon.
So a 10kw gen is really two 5ks. you can run 80% constantly of that with out shut down at sea level. so 80% of 5kw is about 33 amps . If you have two ac drawing 15 amps apeace and you turn on a micro wave or if you turn on anything else that happens to be on that side of the generator it will shut down. so that could be why it seems to be shutting down at different unpredictable times.
so look to see what else is on drawing power. An example would be, you can shut off one AC till food prep in micro is done, then back on with AC.

Ideally one generator, on each side of the generator windings to Keep it balanced load wise. If the micro wave isn't too big --- over 15 amps you should get by with no shut down, but if the tv is on, and you throw two 15 amp loads on might just hold on cooler day, but then someone turns one more thing on, like my battery charger draws a lot of current when battery's are a little low --- no way can a charger and two acs run at once.
Hope this helps
Loren

The OP stated that he has a 12.5 KW generator.

12,500 watts = 104 amps, or 52 amps per leg.

96 Wideglide · 10-31-2020, 01:22 PM

It appears a previous owner has done some of his own wiring.

Don't think any of the Monaco line came wired to run an A/C thru the inverter.

super_rep · 11-01-2020, 09:01 AM

We have an 04 Signature Castle IV. We almost always are running with all 3 AC turned on. We hate to arrive at a campground and have the back of the coach hot. The fuel filter on you generator is a real B***h to replace. But it sounds like you sure need to do so. Get the manual for the 12.5 KW generator and order a fuel filter from Amazon.