Due to a SPUT on my part today, I manage to fry our furnace.
The thermostat decided to stop working, so I removed it, planning to replace it (with one with no moving parts, if possible). It is basically a simple switch that closes the contacts on two wires running to the furnace. Since we didn't have a thermostat, I simply removed it and left the two exposed wires. When we wanted the heater turned on, we just twisted them together, and it worked fine.
When we were getting ready to leave, for reasons that I won't go into, I grounded one of the wires to the door frame of the camper. A very brief "squeak" sound was heard from the heater, and after that, the heater was no longer working (nothing happened when I twisted the wires together again). So obviously, I let the smoke out of one of the components inside the furnace, and of course, the smoke inside is what causes electronic devices to work.
The schematic that is supplied with the furnace isn't very helpful, since it just shows the two thermostat wires going to something called the "module board". This is a PC board apparently with a full name of "fan control module board". It is identified as one part, and the instructions state that individual parts can't be repaired, only replaced.
The only glimmer of hope is that the schematic does show a single fuse for the furnace.
Here are my questions:
1. Does anyone know where that fuse is located, or whether there is another fuse in there that's not shown on the diagram? We were in a hurry to pack up and get home, and so far, I haven't really taken a look.
2. Is replacing the "module board" something I can do myself? If the board is readily accessible, I'm comfortable taking it out and putting in a new one. In fact, if I had a schematic of the board itself (which I realize is probably not available), I could probably repair the damage. However, I am not comfortable removing mechanical components in order to get at it. I know my limitations, and if I have to unscrew too many pieces to get it it, I won't be able to put it back together (or after putting it back together, there will be the dreaded leftover parts).
From the blow up diagram that came with it, it looks like it's in the middle, but I really can't tell. Does anyone know if that's something I can get at without much difficulty?
The furnace is Suburban model DD-17DSI, and the "module board" is part # 520820. It is part #32 on this diagram:http://www.laurelhurstdistributors.com/parts/furnaces/Suburban_DD17DSI.html
For some reason, the fuse holder is not shown on the diagram. To me, part #32 looks hopelessly buried on this picture, but maybe someone here can give me some moral support.