Coleman Gas Furnace

[sboro123]

Model# DGAA070BDTA
The flash code is showing 3 flashes.
I have just paid $360.00 to have the booster motor assembly replaced, due to the motor was extremely load and vibrating so loud.
Now again there are 3 flashes, it seems to be combustion air switch.
The strange thing is sometime the furnace comes on and sometimes it does not.
Before I spend more money, can I fix this myself.
Yesterday, it was acting up in the morning, the Hvac guys came back and furnace was working fine, so they ran the furnace a few times and it was fine, again this morning no heat, and flashing 3 times again. As of this now it is now working,
Need help fast, it is cold!!

[Robert]

Hi,

Make sure booster motor air pipe is not clogged or damaged, tubes to pressure switch are not kinked, clogged, loose or damaged, 24vac to one wire at pressure switch, booster motor and wheel is clean and running strong.


IF all is ok, then pressure switch may be faulty.



Thanks,
Robert