Converter shutdown due to thermal protection circuit

JamesDow

I have an issue when desert camping (108 degrees) and my converter shutting down after a few minutes when attempting to use the air conditioner. The converter fan does work as anticipated. The shut-down is apparently due to the thermal protection circuit. All is fine and is reset automatically when the outside temperature drops down.

Has anyone else experienced this issue. (I would call it a problem when you can not use the air conditioner when it is 108 degrees). I my mind I thought I read somewhere that the thermal protection kicks in at >140.

Is there a way to cool the circuit down besides the internal fan?
Do I have an issue with my thermal protection circuit?

LuckyJ

@JamesDow This is weird, some how, I think I just did answer a similar tread. Anyhow, here are my tought on this.

Did you run the AC vent fan? I know the inverter is not situated at the same place as the AC cooling plenum, but I did notice that when using the AC w/o the AC vent fan on, the back wall (feet wall) would warm up so much that my feet would feel the heat and wake me up. That is when I knew that my feet would have turn the fan switch to off. Turning it on, would quickly rduce the wall temp down, even the part under the Jensen radio with is not alight with the AC vent.

So it could help cool down the inverter as well.

Luc

JamesDow

Yes the AC vent fan was in use. The trailer was in direct sunlight for a good part of the day (could not be helped), with windows and vent open. With outside air temp at 108, I could see the inside reaching near a thermal cutoff point and when the ac is put on and the watts increase as does the ac on (reverse of typical turn on power surge), I can see how temps could get hot enough to trip a protection circuit. Bottom line, the cutoff occurs when you need the ac the most.

LuckyJ

I d not know the ins and out of the jensen, but this is weird, since I would beleive that the Jensen do not do much with the AC current, but supply a braker switch.

Were you using anything esle 12V but the fridge and the AC fan vent?

JamesDow

The only power usage was the 1. Converter 2. AC fan 3. AC.

Nu-Camp has instructed me to contact dealer and have it checked out.

I believe it is related to thermal protection circuitry associated with the converter or a fault in the circuitry associated with high temperature. As it was 108 degrees and the back and top of the trailer was in the sun, I could assume temps at the converter were 30-40 degrees warmer. Keep in mind things worked for about 10 minutes before shut down. Resumed fine by morning after things coold down to mid 70s.

JamesDow

I just realized that I did not mention the Jensen Stereo. That has nothing to do with the converter or the issue. It was off. The only draw from the Jensen while off is the clock, which I set so it does not display. The draw would be like a watch battery. (next to nothing).
For some additional information see the link below: -

https://littleguytrailers.com/power-management/

JamesDow

Update: I contacted WFCO - 877.294.8997 (Maker of the MF-8725 converter) and discussed the issue. They did indicate that the unit has a heat sink which kicks in when the temp reaches 200 degrees. They advised blowing a fan into the unit prior to use when in the extreme heat conditions I was in. -- BUT -- they indicated that that should have nothing to do with the 110 AC, so it would not be the problem and to contact an electrician.
Since none of the circuit breakers trip or fuses blown, my next thought could be the wiring or contact to the main 30 amp breaker. I will likely visually inspect and maybe pull the breaker.
I will provide an update if I find something.
My problem is recreating the problem when I am not already in the desert.

willbingham1

James, last August I was at Lost Dutchman State Park outside Apache Junction, ,AZ, in a steady daily temp of 104 for two days without any issues with charger/converter and AC blowing full time and no shade on trailer. Certainly sounds like defect in unit and probably thermal related. Definitely a warranty issue with unit IF it can be replicated. Try hair dryer at low temp blowing on the unit, up to a point, seeing if you can get it to kick out. Just a thought. Bill

JamesDow

Thanks Bill, I may try the hair dryer, but I also think it is past the warranty period offered by WFCO. (2 yrs)