Chinook RV

I was trying to do the monthly exercise for the gen set this afternoon by using the rooftop AC (it is California here), but it did not make any noise. I then turn the thermostat all the way down, still nothing. Finally, I change the mode to Fan Only, and not even the fan blows air. It is going to be raining for next few days (not typical of California), so I don't know when I am going to try it again, but I will keep you guys informed if I learn anything from this.

Edit:
Correct misspelling of "roof"

I'm no expert by any means, but I would plug the rig into shore power to make sure the AC still works that way, sort of like a process of elimination.
If it still doesn't turn on while plugged in, I would have no way of knowing if the AC is damaged or if there's something wrong with the electrical path to the AC via generator and or shore power.
But if it does work, then I would know it might have something to do with the gen to AC path.
That's how my limited electrical mind would work. Then I'd take it to a shop and overpay someone to fix it for me, only to find out later that it was only a fuse (like the thermostat)!

Hi Ching,

Bummer about the AC. Mine is working, but for some reason lately, it has been taking a long time to kick in. There is a fuse inside of the AC unit itself, which you might look at. It is a very low rating (2.5A I think), to protect the electronics related to the thermostat. I know because I blew it when I was working on some wiring related to the old phone wire. I replaced it with a 5Amp because it was the smallest I had, but it did bring the AC and thermostat back to life.

Another elimination thing:

The ATS (automatic transfer switch) is an item known to fail. If so, it might not switch over to generator but might stick on shorepower as the source (and not "see" the generator). So, what happens if you run the generator (NOT plugged in to shorepower) and try to run something *else* that would need AC power, such as an electric heater (or anything plugged in to a household outlet, really). If that also doesn't work, I might suspect the ATS. (Obviously if you have an inverter, have it turned off so that doesn't confuse things.)

If you do need to replace the ATS, I can post some tips.

That’s a great process of elimination.
I didn’t know about this and I just learned!
So if my coffee maker, microwave, plug in heater, or anything else 110 doesn’t work with the generator on, then it could be that AT switch.
Good To keep in mind if needed in future!

For my case, it is definitely not the ATS because the outside 110 AC plugs still work while the AC is not. It has been raining all day, so I will take a look later next week. Tomorrow will be another wet day.

Well darn, but only sort of, because the ATS is kind of a bear to get to in order to replace.

Next...

Blue, I don't think the ATS is a difficult thing to replace. I got it pull out together with the brown box when I was redoing the shore power cable, and it is pretty easy modular unit to replace. Two sets of input, one set of output. It will be great if you are right, but instead, I feel that I may have to stand on the roof top and take the cover off, check the capacitors, fuses, and wiring.

Right, it is easy to replace, but kind of a bear to access (at least in my Concourse). Reason I say that is not that I actually replaced it, but I did remove the brown box (first step in replacing ATS) and the wiring supplying it was SO SHORT that it was a huge pain to get out of the cabinet. I had to pull it out like 1/2" and then blindly shove a screwdriver in there to disconnect the AC wires. Then I could pull it out and it would have been simple to replace the ATS at that point.

With the gen set off, and connected to shore power, the fan hums but no air movement. I guess it is time for me to check the capacitor and see if that will solve the problem. It is wet on the roof, so I will taking the cover apart later this week.... I assume the capacitor is in there and not accessible from below.