I got Heater Problems. Any ideas??

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On The Road Again

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Apr 29, 2006
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Location
Everett, Washington
OK, it is a 2002 Fleetwood Southwind V32
I can turn on the Coach heater. The blower comes on. It will fire off for about 3 seconds. The flame shuts off. You can hear a click at a (i guess) a relay? after about 5 sec, it comes back on and all this time the blower keeps running. Again, the burner shuts off after 3 seconds. Then back on again. Off in 3 seconds, then the blower will shut off and unless you shut the Thermostat off then back on, and the whole thing starts over again. Now, looking inside the heater box from the outside, on a printed Curcuit board there is a little lite. Maybe an led. When the 3rd cycle shuts off, that little red lite starts blinking for 3 times, then a pause, then 3 times, etc. The stove and refer works fine.  Anyone have any ideas.. I kinda ruled out the cob web thing since the burner will come on. Any info will help. Thanks, its starting to get cold here. *S* Bud ???
 
Sorry I'm not any kind of expert but I thought I'd bump this so maybe it will get
noticed, by chance does your furnace have a seperate valve to shut off the propane?
 
I would have 3 suspects

Suspect number one is Preventive Maintenance, When was the last time you performed it, Solution: Perform it

Suspect Number two is called a "Flame Sensor" this is a thermocouple that sits in the flame and detects that the burner has, in fact, lit.  It may be covered with enough soot to insulate it and may be non-functional  Cleaning it and making sure it is properly positioned may be enough to "Fix" it  Also check any and all connecitons between it and the mother board

Suspect number 3 is the control system (Mother board)

If there were to be a #4 on my list it would be the high temp-cut out.. but I suspect the cause of a problem there is the first item on the list. 

PM involves, among other things, checking for insect nests in the exhaust flu
 
I'd suggest you dig out the manual to see what the 3 flashes mean.  Usually there is a list of trouble shooting hints, and the 3 flashes might be amongst them  If you daon't have the hard copy, I would suggest you google the make and model of the furnace, or come back in with the specifics, and likely someone here will have the info
 
I have seen similar symtoms a couple years ago when a guy came by asking if I could help.  We found that mud daubers had set up house keeping in the furnace vents outside where the combustion air enters and exhaustsfrom the furnace.  We used a metal coat hanger to clean out the duct and all came good.
 
There are multiple safety cut-outs in the furnace and most likely one of them is shutting the gas supply off. The gas will go off if the flame sensor does not detect a flame in the burner (that can happen even if the flame is in fact burning) or if internal temperature gets too high. The latter is unlikely in a few seconds, so the flame sensor is the most probable explanation.
 
What you described is normal for an abnormal condition - Got that? The flashing light tells you that it's done trying to light the furnace for safety reasons, and has gone into lock-out mode. Turning off the thermostat and turning it back on restarts the cycle of 'three strikes and you're out".

With you outside the coach and someone inside, look into the burner tube. Locate the ignitor spark wire - it will be connected to the control board, probably clipped or screwed to the top of a small, round plastic thingy. That's your spark coil. Now have that person inside turn the furnace on. Is the tip of the ignitor wire directly in the flame? It should be. It also serves as the flame sensor and if it isn't IN the flame, it won't work properly. If necessary, loosen the attaching screw and position it properly. Be careful not to break the porcelain insulator that it's mounted in. Also make sure the other end of the wire is securely attached to the spark coil. A loose or dirty connection there can block the flow of the very small sense current while still allowing the much higher voltage spark to ignite the furnace.  Check the flame to make sure it is a clean, blue color. If yellow, that almost surely indicates some kind of blockage in the burner tube or exhaust, or the sleeve that controls the fuel/air mixture has somehow been moved; not likely, but possible.
If none of that does the trick, you're most likely faced with replacing the control board.
 
THANKS everyone for your help. Well, I do the preventive maintenance on it every spring along with everything else. . Maybe it is time to do it again. It worked fine about a week before as I had it all all night because of the cold weather. It does not have a seperate shut off that I can find. It is suppose to be nice here the next few days, sun and low 40's so I will start taking things apart and see twhat I can find. If I find it, I will report back on this tread with my solution. Thanks again, Bud
 
I had a furnace that was acting funny and just took it into the shop and they said that something on the circuit board had gone bad and they had to replace the whole circuit board.  That may be  your last resort but that may also be your answer.
 
;D Once again, thanks for all the help. I love this site and the people who so kindly give their time and experience to help others. I pulled it all apart. As usual, not a trace of soot. It was as clean as sould be. The burner had a bit of rust from Condensation so I got it all cleaned and blown out. Cleaned Orfice and put it back together. The exhaust was clean, but cleaned it again. Checked out all wireing and removed the harness from the circuit board, cleaned both. Put it all back together. Kicked it on and it ran for a few seconds then shut off, then came back on and stayed on. I started it at 50 degrees, then after it reached that temp and shut off, I went up to 55. Then 60, now it is at 70 degrees. It is holding the heat at the temp I set it at. I think the reason that it shut off at the first cycle, was because it was looking for gas after removing the gas line.  Oh, this is an Atwood 8500-IV if anyone is interested. My fingers, legs and eyes are crossed. If this does not continue to work, then it goes to the shop.  Or, I will buy a new curcuit board on-line and give that a try. If you do not hear back from me, you will know that the problem is solved. Thanks again and lets look for a great summer and LOW gas and Diesol Prices.  :D Bud n Ann  PS, I do not look for misspelled words. Its more fun that way. lol
 
Firefox has a speil clunker built in, so I hardly ever use the forum one cause firefox's one is good at finding miss steaks.

(No, that was intentional, both of them)

Recall that one of the possible suspects I mentioned was the connections to the mother board?

You cleaned them.  Cleaning the burner was a good idea too
 
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