Comfort Pro Apu Issues (solved)

Looking to install a used 2018 comfort pro. Does it have a fuse on the positive to the batteries like Thermo king units? Didn’t come with one.

 

Nothing in a Comfort Pro runs off of the truck batteries. The APU only charges them. The 120 volt AC, the air compressor, and the heating elements all are powered by a big generator in the APU. That does have a circuit breaker on it.

 

Thanks for the quick reply. Can the 120 volt AC handle a microwave safely or having an inverter the way to go?

 

As long as it is a small wattage microwave you're OK. Mine is 700 watts and it has never given my APU any trouble.

 

You should check the voltage at the outlet with a multimeter, it should be 110-130vac at 60hz. If you’re running the hvac or the heater it will draw more voltage, so you may want to turn them off while you’re using the microwave.

 

Check the alternator output. The board runs off the 12vdc from the app alternator, so if that isn’t working you won’t get anything. Sometimes fixing them is as simple as unplugging the voltage regulator at the back and cleaning the contacts out, they get corroded a lot and it doesn’t take much to mess with the signal voltage.

 

There will be cables to the starter and I think a small wire to the board to power the control panel. Pretty sure it should have a fuse but I’m not sure what amperage. Probably 5 but I would check the manual.

 

Lots of good information here!!!

 

Getting warm air during AC cycle. The fan on the rear of the truck isn't coming on either. I tried recharging the refrigerant but it was already over filled. The APU runs like a top. Heater works great. 110 outlets work as intended. Think the condenser is fried? It's not icing up under the bunk. I'd like to repair or replace any parts myself if y'all got any ideas of what my issue is. Thank ya!

 

Replace the condensor fan, it's the fan on the back of the truck