o1xtrem
Pontotoc, MS
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I tried to use my furnace for the first time since owning my 2000 Coachman this past weekend. I tried 2 times, and it blew the 15 amp furnace fuse in the fuse panel both times. I am assuming this fuse has something to do with the thermostat on the wall because it would blow the fuse, then the Air conditioning wouldn't turn on either. I could replace the fuse, air ran fine. Tried the heat again, it blew the fuse. I'm thinking there has to be a short or something somewhere. My question is, how do I go about finding it?
Any help would be greatly appreciated.
Thanks.
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Artum Snowbird
Campbell River, B.C., Canada
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Joined: 05/28/2004
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Furnaces are usually plugged in. If you can find the plug in place, get an electrical cord that goes to a breaker and plug the furnace into that. Did it blow...then it's inside the furnace. Did it not? Then it's inside the wiring in the Coachman.
I presume you are checking the furnace with the A/C off. Both on might cause an overload. Did you replace the fuse, then try only the furnace? Then add the A/C...then did it blow?
A sudden blow usually means a dead short, a slower blow...even a couple of seconds or more after applying power means an overload.
Mike and Carole
2006 Triple E Regency 27 foot SXL
2005 16.6 Double Eagle
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Dr Quick
M'boro, Tn
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Most newer thermostats that combine heat and cool have two circuits to furnace for heating. One sends power to furnace and the second controls calling for heat.
Did it blow as soon as you turned thermostat switch to furnace? Then problem is probably in wiring to turn furnace on. If it blew when furnace tried to cycle then problem is in that wire. If it blew a few seconds after heat was turned on, then problem is probably in furnace.
I once had a mud dauber get in my furnace combustion air intake and it built a nest on the combustion fan wheel, and when nest came loose it locked up fan. Fortunately the blower motor had a overload and it cut blower motor off.
If problem appears to be in wires I would disconnect wires at each end, mark first, then check for a short between wires. I have heard where a nail or screw has penetrated wires.
If problem is in furnace you will need a wiring diagram to trace out circuits for a short.
Hope this helps.
Dr quick
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just me
Salt Lake City Utah USA
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Maybe you have a hornets nest in there and the fan can not come on, or something, causing the malfunction.
95 Dodge CC #5 TST plate Flame Red/Silver
not totaly stock
2007 fiver
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big dave
Soldotna, Alaska, USA
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Most likely something preventing the blower motor from turning. It could be dry bearings, but as already stated, it could be a nest of some kind. Either way, it needs to come apart.
Dave & Rose C
90 Safari Ivory 34' DP
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o1xtrem
Pontotoc, MS
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Thanks for the help, I'll check tomorrow to see if I can find a next of somekind. I took the cover off outside, and it looks clean in there. But I didn't check the fan or anything. Didn't want to mess anything up.
There is no plug in for this furnace, my thermostat has heat an air on the same control, so there is not way to run the air and heat at the same time.
As far as it blowing the fuse, I turn then switch to heat, and then heard a click, which I thought it was trying to light, but come to find out it was the fuse blowing.
I'll check more into things tomorrow and let you guys know what I find. Thanks again.
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stevesandidge
kingsport tn
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its dc, not ac, with gas doin the work. if this is the 1st time you have used it, the nest thing is probable. if you have used this frunace much, it is most likely bearings in the motor was it making noise when it tried to run before?
steve
steve sandidge
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91 holiday rambler imperial 37'
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o1xtrem
Pontotoc, MS
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Well I checked it out today, and seems there are some nest in the fan in there causing the fan to not spin freely. Question I have is how do I get in there to get them out? Its very tight, and the fan has covers over it and I don't see anyway to get the cover off so I can get the nest out. Can I use water or air? Only way I can think of....
I have never used the furnace. I puchased it used back in April, and I haven't had to use it at all since I purchased it. Seems to be a nest issue, just got to figure out how to get them out. Any help would be appreciated.
Thanks
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tafische
Memphis
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Joined: 10/14/2009
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Probably the only way you are truly going to get it out is to pull it. Blowing it with air is probably going to push it elsewhere...water? sounds like a bad idea!
If you have the model number, you should be able to find an install manual online. That should help show you how it is put together. Usually it is a tricky puzzle, but once you figure it out - not so bad 
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