120v and generator…

[modrob]

I would check gen output at the gen. The issue with many Onan generators is the field compensation circuit. This circuit changes the field voltage to manage voltage sag. Although its been some time, as I recall it has brushes. You might check them for possible replacement next.

Whew! By the time I get this coach in shape, I’ll be a full-fledged tech! LOL Problem is I have other major projects going on and I have to squeeze the RV in when I can…I guess I have to finally admit to myself I got taken pretty good on this coach. I’m about sick with all I’ve found and more to come I’m sure…totally my fault by not doing a thorough inspection and trusting the old couple sellers.
Thanks for your help and guidance.

 

[Kevin D Pem]

Whew! By the time I get this coach in shape, I’ll be a full-fledged tech! LOL Problem is I have other major projects going on and I have to squeeze the RV in when I can…I guess I have to finally admit to myself I got taken pretty good on this coach. I’m about sick with all I’ve found and more to come I’m sure…totally my fault by not doing a thorough inspection and trusting the old couple sellers.
Thanks for your help and guidance.

My mom used to say as people age they become worse images of what they were when young!!! Just because you see white hair doesn't mean they can be trusted!!! Till the day she passed, she had a mellow soul, she must have been a joy to raise!!!

Oh if no brushes the excitation coil in the field would be my diagnosis.

 

[modrob]

UPDATE:
Finally got around to looking deeper. There are only two breakers on this unit, on left side, to the right of the Start/Stop rocker switch. Evidently I couldn’t read the labels clearly and had them OFF instead of ON. Corrected that, and voila! 120 volts now showing up inside. Curiously, I turned on the FAN switches on the overhead AC units, but nothing. Hmmmm…

 

[TheLooks]

Put up a pic of the AC unit and thermostat. By pic I mean the inside cover on the ceiling and any lettering on it.

 

[modrob]

Put up a pic of the AC unit and thermostat. By pic I mean the inside cover on the ceiling and any lettering on it.

I’ll have to get a pic of the thermostats soon…but here are the labels inside both roof units.

 

[TheLooks]

My guess is if you turn on the AC or heat unit and nothing happens it is either in the control box in the AC unit or the thermostat.

 

[modrob]

My guess is if you turn on the AC or heat unit and nothing happens it is either in the control box in the AC unit or the thermostat.

A few weeks back (warm weather) I had both units working fine (cooling) but was on shore power…

 

[TheLooks]

Shore power or 120 vac is necessary for the AC unit to run, but it still is controlled by 12 vdc. The furnace only runs on 12 vdc so unless the battery is dead and the convertor is dead, it will run without 120 vac. The fans on the AC units need 120 vac to run but are TOLD to run by a relay controlled by 12 vdc.(thermostat and control box in ceiling AC unit) Check your voltage with a meter and check the fuses.

 

[modrob]

Shore power or 120 vac is necessary for the AC unit to run, but it still is controlled by 12 vdc. The furnace only runs on 12 vdc so unless the battery is dead and the convertor is dead, it will run without 120 vac. The fans on the AC units need 120 vac to run but are TOLD to run by a relay controlled by 12 vdc.(thermostat and control box in ceiling AC unit) Check your voltage with a meter and check the fuses.

Yes sir, I understand. The furnace part I haven’t started to look into yet—propane is empty anyway…but I’m sure like everything else I’ve been finding, it’ll have issues as well…
All batteries are new and charged…(2 coach and 1 chassis)
I’m just confused for the time being on why AC units/fans would work on shore power, but not with genset running…all breakers/fuses appear to be good so far too.
I’ll keep reading your reply a few more times—I may be missing something…

 

[TheLooks]

Nope, you got it. I would check the transfer switch now. It is supposed to automatically go to generator when the shore power is removed.....or if you have an old system, you have to plug the generator in manually in the electric bay.

 

[Kevin D Pem]

I was just thinking!
Your system was working during the summer right? So is the temperature warm enough for the A/C to kick in?

 

[modrob]

Nope, you got it. I would check the transfer switch now. It is supposed to automatically go to generator when the shore power is removed.....or if you have an old system, you have to plug the generator in manually in the electric bay.

Yes, the auto switch is working but…are you saying I could possibly have the generator running, as well as the shore power plugged in, then I can unplug and the generator will then switch and supply the power? I was afraid to try that with both sources running at the same time…

 

[modrob]

I was just thinking!
Your system was working during the summer right? So is the temperature warm enough for the A/C to kick in?

Yes, AC units were working fine in the heat. (I did have to put in new caps in the rear unit but they both worked fine after that.

 

[TheLooks]

If you have an automatic transfer switch, it will chose the source. It will always go with shore power if it is available. Some units, mostly 30 amp, will have a male plug coming out of the generator and a female plug near it. You must plug the generator in to use it. It makes you the transfer switch.

 

[TheLooks]

If you have 2 AC units you probably have a 50 amp unit but I have seen 30 amp units with a switch where you select which AC is going to run.

 

[Kevin D Pem]

If you have 2 AC units you probably have a 50 amp unit but I have seen 30 amp units with a switch where you select which AC is going to run.

My Winnebago had 2 ac units, and 30 amp service, where both could be turned on at the same time. First thing I had to do was replace the cord cap on the ambilical cord. Because the vents were factory, I assumed that was a Winnebago blunder.

 

[TheLooks]

They must have been less then 13,500 units. I can't turn on anything in my camper that takes any power if the AC is running. That is microwave, hot water heater.

 

[modrob]

Yep mine is set up for 50 amp service, but I was only able to wire up an outlet for 30 amps. (Logistical concerns) I know that I can only use one unit at a time, and that shouldn’t be a problem here at home. (What time I’ve spent in it since buying has been repairing!)
Also, I’m familiar with the gensets that had the male plug that had to be plugged into the female outlet on board—I had two 80s units a few years ago…

 

[Kevin D Pem]

They must have been less then 13,500 units. I can't turn on anything in my camper that takes any power if the AC is running. That is microwave, hot water heater.

I wouldn't have a clue! I always traveled with it to follow the temperature! As I recall I seldom turned them on. I was always off grid! Did run the generator if needed, but at 2hrs a gallon, the economics turned me off completely!!!