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Does this happen when hot out?
Thanks...is ac on the unit?
In that case the only thing that can bring on the blower is part 7975-3281 blower switch.
It is apparently weak and making nuisance contact. It is 120 degree f switch with a 20 degreef differential. This switch is bad/weak.
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You are correct...same scenario but is logic board. 7990-320p
see here - http://www.mobilehomerepair.com/ColemanCheatSheet.html
Sorry, lost connection.
That is correct. The blower function on te circuit board is defective but it requires replacement of the whole board.
I will look for the schematic....but it is going to be of little help. Without cooling there is only one contact point to trun blower on....not the usual 2 or 3.
So if the blower is coming on it means that one contact point is closing. It cannot be blamed on anything else. I will look for the schematic for you.
That is the issue with schematics involving circuit boards. The blower operation is all done internally on the board. With ac there is an external signal. But no ac = all blower activity is controlled via a relay and timer on board....and circuit board diagrams are not present on schematics because they are not field serviceable.
I have checked for the DGAT schematic and have found it is not well supported with online documentation. The furnace is a builders grade that hits a affordable price point without too many features or options.
I apologize but I will not be able to supply a schematic....and even if I could it will not show circuit board detail.
I wish you luck!
That is what is terrific on this site. If a contractor came to your home and said the exact same thing, you cannot say "I dont think that is much of an answer" and not pay the bill.
The end result is the same no matter how it is addressed - The control needs to be replaced. Whether free forum or contractor or paid answer site - the answer is correct and does not change result.
I really dont know what could have been satisfactory...The relay on the circuit board is not even on schematics as the circuit board is shown as a component and not broken down in drawings. Plus you cannot repair just the relay on the board.
I thank you for your time and will opt out...and I wish you luck on replacing the circuit board.
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Comments - Answer provided, customer not satisfied.