Power Problems with HVAC on Generator

[zigzag930]

Not to hijack RyanB's thread on Power Problems with AC, I have created this separate thread on an issue I discovered this weekend.

I have never attempted to run our 16KBTH 220V HVAC system or any of the HVAC systems on my Northern Lights 6K genset as I've always just run off our large Genset.

This weekend I decided to try the smaller Genset as our larger unit is running hot and needs my attention to clean the heat exchanger (which will happen in the next few days).

Anyway, the 16KBTU system ran perfectly all day (about 8 hours) along with some refrigeration and other electronics (TV, etc). For some reason after running all day, all AC power went out on us. No breakers tripped on the Genrator or on the main ships panels. The red AC voltage light on the ships panel was very dim. I turned of the HVAC system and all the power came back on. I didn't reset any breakers or any other devices. Just turned off the HVAC system.

I decided to try this again today and the same issue happened after about 2 hours of running. All AC power (lamps, TV, etc along with the HVAC) went out again. As soon as I turn off the HVAC system, all power is restored.

I sent a message to N. Lights to ask if there is any sort of thermal reset on the generators and was told there is not.

I don't really know where to look at this point because nothing is "tripping" anywhere. Could this be a voltage regulator overheating?

 

[carolinacoast]

The experts will chime in why, but our #2 does the same thing. 3 things cause this on ours. Reduced fuel flow (filter), overheat, or overload will take the power generation offline. We added an air handler for the salon that spools up to reduce the amp draw on startup. I would not have thought that a 6kw could run your size AC, though. Our #2 is a 12.5kw. We have to shutdown and restart to restore power, and no breakers are tripped. The #1 runs everything without a concern on the loading.

 

[Pascal]

When power went out, did it go suddenly or did the lights dim for a moment?
Did you hear the gen struggling and loosing RPM due to the load?
What were the voltage and frequency readings after it went out?

 

[zigzag930]

I did not hear the genset struggling or sounding like it was loaded down. Lights may have dimmed for 1/2 second, but hard to say. Power went off and as soon as I turned the HVAC off it all came back on.

I need to verify the voltage on the ships panel next time I lose power with this issue.

Will report what I find.

 

[Pascal]

So it’s not a mechanical issue like fuel restriction.

Do you have to turn off and restart the gen or does just turning off the AC fix the issue ?

It sounds like something on the generator is taking it off line when load is too high but then it self resets

Have you try loading up the gen with other loads but not that air con? Like water heater, oven, burners... and see if the same thing happens.

 

[zigzag930]

I don't think it's mechanical as in breakers, etc.

I don't have to stop and restart the generator. All I have to do is turn of the this particular HVAC.

I have run lots of other appliances without seeing this issue, but none are 220V. I have tripped breakers on the 110V side when drawing too much on a leg, so I know the breakers work.

You are correct in saying "something is taking the generator off line, then resetting automatically when the HVAC is turned off"