Welcome to the CRVL Forum
Your ability with restoring musical instruments could serve you well out there on the road.
It shouldn't be too difficult for you to learn to trouble shoot or even repair the furnace or generator in your
rig.
A friend of mine who passed away a little over a year ago used to do a lot of repairs on RV Generators. He owned
a 3 phase electric motor shop and repaired generators, motors, welding equipment. He explained to me that if the motor was running but the generator wasn't putting out it was usually a commutator/brush issue. He had this tool that was a special stone on the end of a plastic handle. While the generator was turning (motor running) he would touch this to the commutator and pull it across to clean the commutator. And that would restore the out put in a lot of cases. He said it was similar with welding machines. Often these things sit around and oxidize and if it is the case it is easy to fix.
As for the furnace there are some youtube videos I've seen for the maintenance, repair, and even "ticks"
one can use for their furnace, absorption refrigeration, or generators.
A $20 commutator cleaning stone is lightly drawn across the commutator to clean it to restore it to output.
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