I have two furnaces in my RV--one up front and one smaller one under my bed that heats the back part of the unit. Last week, I left the vehicle parked for four days while visiting my aunt and uncle in Georgia. I had no hookups so was entirely on battery. Because it was below freezing a couple of nights, I left both furnaces on low.
I did not notice anything, but early one morning drove to my next stop. That night, I noticed that there was a hum from some kind of electric motor coming from under my bed, even though the furnace was shut off by then. (The furnace does work when I turn it on, however.) I was worried about burning something up, so I shut off the fuse that controls that motor and furnace. Whatever this motor is, it does NOT sound like the furnace blower because it is a lot quieter. It has been fairly warm here so I have not needed the heat.
I keep forgetting to call the factory customer service, but this afternoon, I experienced a brownout--meaning that my refrigerator light was off andmy ceiling lights were dim, even though I am now connected to outside power. I went across the street to ask some people if they also were having a brownout. The answer was no, but the guy came over and looked at my panel. He said it was probably a sine wave inverter (or something) and said it was charging my batteries so to turn the circuit breaker back on. As soon as I did, the lights brightened and the refrigerator light worked.
So it has been several hours and I can still hear that mystery motor running. I cannot get into the area because there is a plywood panel covering it all up.
I am going to call first thing in the morning, but does anyone have any idea what this motor is and why it is still running??? Does what he said make sense?? (He is apparently a retired mechanical engineer, not an electrical one, but seemed to know what he was talking about.)
To make things more fun, I also had a leak under my sink tonight, whihc I think I fixed. The drain pipe from one side came loose and was dumping water under my sink, which of course is lined with some sort of carpeting!!! I have screwed the pipes together and taken everything out so it can dry. Why would anyone put carpeting under a sink, by the way????