Foretravel Owners' Forum For owners and Fans of Foretravel Motorcoaches September 11, 2025 ...

generator and air conditioning

April 27, 2017, 02:12:48 pm

When I turned on the gen set it seems to do some funny things when I try to run the A/C.
At first under no load the board shows a rapid fluctuation between 13.5 and 14 DCV
It also shows fluctuations between 10 and 20 DC amps.
VAC shows fairly constant between 119 and 122.
What spooks me is when the A/C kicks in the voltage will drop down to 110 volts for just a second then pick back up.
Should I be concerned, or is this standard operating procedure?
Thanks,
Len

Quote Selected

Re: generator and air conditioning

Reply #1 – April 28, 2017, 01:36:11 pm

An additional post now that we have data connection available (parts of TN are a no go)

The numbers I was quoting were off my Freedom Heart interface and the power watch meter.
The only additional things I can add are that when I was running the A/C off the generator in a Walmart parking lot, at one point it kicked off the heart interface entirely and then kicked back in after a few seconds (before I could get to the gen set off switch).

Again, we have been living power post to power post and are wanting to be able to get off grid a little, but don't want to fry something by powering up the gen set.

Any help would be greatly appreciated.

Len & Deb

Quote Selected

Re: generator and air conditioning

Reply #2 – April 28, 2017, 02:51:25 pm

I can't comment on the Heart interface but when we turn on the AC, there is a built in delay for a minute or so and when the AC compressor comes on, the AC voltage does drop down during the startup load and then returns to normal.

Pierce

Quote Selected

Re: generator and air conditioning

Reply #3 – April 28, 2017, 03:12:31 pm

Our Powerwatch bounces as well.  The digital meter shows very small variations.  I was told this is normal for the genset with the AC because of cycle difference.  I don't know enough to say more than that.  We never had the issue you describe with the Heart before we changed it out and none with the Victron.  On the post there is no needle bouncing and with the genset no bouncing except with AC running. 

Quote Selected

Re: generator and air conditioning

Reply #4 – April 28, 2017, 05:01:53 pm

x2 Pierce.

It is normal for a gen set to "load up" when load comes on line like your ac.

Even at your home when a load comes on, your voltage will drop a few volts

and will recover. When a load is applied to your generator it takes a moment

for the generator to react. The gen then increases the fuel to compensate for

the added load.

Have fun away from the power  post,

Carter-

Quote Selected

Re: generator and air conditioning

Reply #5 – April 28, 2017, 06:02:17 pm

The bounce is continuous.  Expect the drop when it kicks but it reverts to a smaller range and just keeps wagging.

Quote Selected

Re: generator and air conditioning

Reply #6 – April 29, 2017, 01:07:46 am

My gauge bounce was bad fuel lines

Quote Selected

Re: generator and air conditioning

Reply #7 – April 29, 2017, 08:39:13 am

Bob,
When you say your bounce was due to fuel line issues, once those were corrected did it go to rock steady on the voltage gauge?

While I am at it, thanks to all for your input. I had never run the gen set while I was sitting there staring at the board, so I had no idea what to really expect.

Hope you are all having a great Saturday. We are off today to see the Jack Daniels distillery. Being a "Tennessee Squire" it is like a pilgrimage. I wonder if anyone else on the forum is a Tennessee Squire.

Len

Quote Selected

Re: generator and air conditioning

Reply #8 – April 29, 2017, 09:46:22 am

Quote from: Caflashbob – April 29, 2017, 01:07:46 am

My gauge bounce was bad fuel lines

If bad fuel lines were your problem, you should have heard the gen set surging.

Quote Selected

Re: generator and air conditioning

Reply #9 – April 29, 2017, 08:15:44 pm

Len,

Gen sets can fluctuate some. You have a very accurate power measuring device.

What would never be seen on older coaches. Sometime TMI is not good.

Carter-

Quote Selected

Re: generator and air conditioning

Reply #10 – April 29, 2017, 08:42:08 pm

Yes bounce stopped you would have thought you could hear it but not that I could tell.

Quote Selected