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Topic: Switch from coach Onan gen to portable gen? (Read 551 times) previous topic - next topic

Switch from coach Onan gen to portable gen?

Just got to ask.
As almost anyone knows, the onboard 1989 Onan air cooled propane fired onboard generator is noisy as he**.
We bought a portable 2500W inverter generator for Christmas just so we could keep the batteries charged while boondocking.
So here is my question: If I start the onboard Onan generator and let it run long enough that I can turn on one roof AC, then while it is running, could I fire up the portable generator (hooked up to the shore power cord) and then turn off the Onan? Would the AC keep running?
And don't say we should buy a "soft Start" Coach is too old, we are too old, our time with the coach is counting down so payback doesn't compute.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Switch from coach Onan gen to portable gen?

Reply #1 –
Quote from: nitehawk –
So here is my question: If I start the onboard Onan generator and let it run long enough that I can turn on one roof AC, then while it is running, could I fire up the portable generator (hooked up to the shore power cord) and then turn off the Onan? Would the AC keep running?
Does the compressor on your A/C unit cycle on and off (to control the set temp)?  If so, it won't matter if you start the A/C on the Onan and then switch to portable, or just start out from scratch on the portable.  Every time the compressor cycles off and then back on the portable generator will need to support the max lock rotor amp (LRA) load.

2500w is about 20 amps at 120 volts.  You should be able to look up the rated LRA draw of the A/C unit somewhere.  More than 20 amps?  Anything else (120v powered) running at the same time?

What I would do: try it and see what happens.  Either it will work, or it won't.  Probably pop the circuit breaker on the portable generator if too much load.  Not likely to let smoke out.  You hope.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Switch from coach Onan gen to portable gen?

Reply #2 –
Not likely your AC keep running, just not quick enough change over. 2500 watts likely will but start your ac. One way to find out give it a try, won't hurt anything.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Switch from coach Onan gen to portable gen?

Reply #3 –
I'm not sure what size AC units you have but if I recall correctly, a Honda EU2200 that is properly jetted for it's elevation will get a 13k BTU going without a soft start. I have heard that the Hondas and Yamahas reach a higher true output than some of the cheaper generators though so take that for what little it's worth. I agree with bbeane, give it a try and see what happens.
1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.

Re: Switch from coach Onan gen to portable gen?

Reply #4 –
Last year we were running our roof ac on the Honda 2200  BUT batteries had to be charged.  If I started the ac and much of anything and I mean anything else was drawing power it would kick out. 
  I had to make sure the batteries were charged but if they were mostly charged the Honda would run the ac and keep up.    No microwaving or hair drying either.

  What I really wanted to do was hard plumb the Honda into the nose of the GV but ended up getting solar panels and lithium instead.  Batteries always up now.
Robert and Susan
 1995 36' 280 WTBI 8.3 3060r
 1200 watts on the roof, 720 Ah of lithium's
 Build # 4637. Motorcade # 17599
        FMCA  # 451505
        18  Wrangler JLUR

Re: Switch from coach Onan gen to portable gen?

Reply #5 –
Guess I am going to have to wait until we get the coach home to try it.
First--cataract surgery.
Then L4 back epidural treatment.
Then--right eye cataract surgery.
Thanks everyone for the suggestions and recommendations.
I am sure looking forward to giving them a try.
When we are the only ones up north in a deserted CG I still hate to hear that Onan howling three city blocks away thru the woods.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Switch from coach Onan gen to portable gen?

Reply #6 –
I know that feeling. I can step out of a building a hundred yards away from our coach and know if the DW has started the geny.  It has a particular hum/growl.  And that is when there's a few other genys running also.
Robert and Susan
 1995 36' 280 WTBI 8.3 3060r
 1200 watts on the roof, 720 Ah of lithium's
 Build # 4637. Motorcade # 17599
        FMCA  # 451505
        18  Wrangler JLUR

Re: Switch from coach Onan gen to portable gen?

Reply #7 –
It won't switch fast enough not to initiate a start load and with air conditioning the load may possibly be even higher than a normal start do to head pressure. Modern air conditioning units if they see a power loss will lock out for a minute before they restart just for that reason.
Scott

Re: Switch from coach Onan gen to portable gen?

Reply #8 –
 My 5.5 is quiet . It is marked as  Cummins- Onan RV QG.  it is in a sound reducing case .  Very nice . I'm guessing that it is about 2010 vintage as most of the systems were updated then . 
 Maybe you can retrofit the enclosure .

Re: Switch from coach Onan gen to portable gen?

Reply #9 –
It is NOT the enclosure. I tore out the old sound insulation and replaced it with newer stuff. The noise comes from the air intake for cooling. Just plain loud.
I heard Triple Nickel's 1989 Foretravel GV generator (same as mine) and it is just as loud.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Switch from coach Onan gen to portable gen?

Reply #10 –
Quote from: Protech Racing –
My 5.5 is quiet . It is marked as  Cummins- Onan RV QG.  it is in a sound reducing case .  Very nice . I'm guessing that it is about 2010 vintage as most of the systems were updated then . 
 Maybe you can retrofit the enclosure .

Apples versus Oranges.  When the Onan Emerald* series were produced, they were fantastically quiet, at 30 feet the loudest thing you could hear was the cooling air.  Right now we're doing our monthly 1-hour run and with the front air-conditioner on high, Lynn asked "Are you still running the generator?"  Compared to the latest and greatest, however, they're noisy.

*Onan opposed 2-cylinder air-cooled engines, driving Onan alternators, with Onan electronics.  Lots of room for improvement.
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.
 

Re: Switch from coach Onan gen to portable gen?

Reply #12 –
OH no! more like this one
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD