Air conditioner & generator

[triplewide]

A clamp on amp meter used at each circuit in your distribution panel will tell you where the amps are being used. You can also test total amps to distribution panel from generator.

At this point you don't know if the the issue is your generator's output/performance or if you have an appliance/load using too much.

The amp meter will tell you which side of the system, input/output, is the issue.

[ladytj1754]

Thank you, everyone, for your thoughts on this issue! Having read all the replies, we decided to troubleshoot all the appliances with the generator, including air conditioner.

We started the generator with no appliances on, let it run for about 10 minutes, then started turning on various things like the microwave, the TV, the fireplace, etc. the generator never missed a beat! Finally, we turned on the front air conditioner and left the back one off. Ran like a charm for over 30 minutes!

Conclusion: start the generator with it in the ‘out’ position on the front of the coach, with everything off. Let it run for about 5-10 minutes. Then turn on only the front air conditioner and leave the back one off. Seemed to make all the difference! Did not add the back air during this test.

Marilyn & Jim Godfrey
2007 - 34DDS

[RVPioneer]

Originally Posted by ladytj1754

Thank you, everyone, for your thoughts on this issue! Having read all the replies, we decided to troubleshoot all the appliances with the generator, including air conditioner.

We started the generator with no appliances on, let it run for about 10 minutes, then started turning on various things like the microwave, the TV, the fireplace, etc. the generator never missed a beat! Finally, we turned on the front air conditioner and left the back one off. Ran like a charm for over 30 minutes!

Conclusion: start the generator with it in the ‘out’ position on the front of the coach, with everything off. Let it run for about 5-10 minutes. Then turn on only the front air conditioner and leave the back one off. Seemed to make all the difference! Did not add the back air during this test.

Marilyn & Jim Godfrey
2007 - 34DDS

Your results are inconclusive. As suggested by triplewide, metering each device will provide valuable information. You have not recreated the condition which was causing the generator to shut down. Therefore, the "problem" remains undiagnosed. It could be the charger running at "max charge" (17-20A) in combination with one AC unit at (11A). It could be an appliance drawing more Amps than it should if it were functioning properly. It could be a loose or corroded electrical connection.



I would certainly want to know that there is not a hidden electrical problem somewhere in the coach. Realistically, with the generator, you should be able to run both AC units and the charger with the power share setting at 15A.


Finally, starting the generator with the slide out would have no effect on its performance.

[Parkereng]

Originally Posted by Wil Rathke

This condition is well documented. It is a conflict between the engine alternator and the Onan generator charging the house batteries. The work around is to: before starting the engine, start the Onan gen, then turn off the Xantrex charge function on the control panel, then start the engine. The generator should continue to run. The house batteries will be charged from the engine alternator.

My brother has a 2008 34fdds and had the same problem. This was the fix for him also.

[vsheetz]

Originally Posted by Barbaraok

I can turn off the charge function at the remote panel - and do so when we are running down the road.

On my Xantrex one can only turn off the inverter. But not the charger. Charger is always active with shore or genny power applied.

[TheKassman]

I have done the same. On a trip now and have been running the 7500 QD 12-17 hours a day while driving and parked and so far no issue.

[Yankeebelle]

Would having it overloaded also create a condition where in the switch box (the one that has contactors that goes from shore power to gen power) would make the contactors chatter and not engage. When we first got this one, we had tried to run the gen with both AC's and it would do that chattering with the contactors and the gen engine would race up and die. When we cut it to just the front AC it would do fine. We've never tried it again. But had another motorhome in the past I could always run both AC's with it, but did not have as many options to it back then. After reading all these posts will have to look at the charger and see if turning it down or off makes a difference.

thanks
Bruce

[DrDaveMA]

There are a couple of known issues that have been discussed in prior threads being covered in the above postings.

First WRV had problems with the terminations in the AC line junction box mounted on the ceiling about 3/4 of the way back in the generator compartment. It was either loose connectors (wire nuts) or just poor connections. Open the box with the generator shut off and check these connections (take them apart and twist them back together with new wire nuts of the proper size for the conductors).

The second issue is the ATS (Automatic Transfer Switch), the default is to the generator, that is why about 15 seconds after you plug into shore power you hear a loud thunk, you should never operate the ATS under load (shut off the A/C or other large loads before you switch from shore power to genny or vice versa) the 30 plus amps that could be running through the ATS contacts when the A/C’s (or microwave) are running will burn and pit them. If your ATS is chattering change it, the coil is probably weak and the contacts have become pitted, the chattering will stop, unless there are other issues like the bad connections in the generator compartment mentioned above.

[Yankeebelle]

Thanks Dave. I'll have to check the box out near the generator. Easy enough to check that out.

Will also make a point to make sure everything is turned off before I start the gen. Know the ATS is fairly new. The PO said it had been replaced and the old one was still sitting on the floor in the storage bay. It only did that chattering once and think I had too much on at the same time for it. I'll start the AC's one at a time and also check out the battery charger to make sure it's turned off or down. Another item to add to my preflight checklist. Growing everyday it seems

Bruce

[DrDaveMA]

Originally Posted by Yankeebelle

Thanks Dave. I'll have to check the box out near the generator. Easy enough to check that out.



Will also make a point to make sure everything is turned off before I start the gen. Know the ATS is fairly new. The PO said it had been replaced and the old one was still sitting on the floor in the storage bay. It only did that chattering once and think I had too much on at the same time for it. I'll start the AC's one at a time and also check out the battery charger to make sure it's turned off or down. Another item to add to my preflight checklist. Growing everyday it seems



Bruce

Just be sure to manage the A/C units, the charger is ok to leave on.

[Dudley do-right]

There are two "don'ts" to follow for any generator use: Don't start 'em loaded, and don't shut 'em off loaded.
Dudley Do-Right, '06Apex40MDTS