Trane XE90 HELLLLLLPPPPP!!!! - http://www.hvacmechanic.com/ Forums

Original message

mollydodger

70.246.135.239

"Trane XE90 HELLLLLLPPPPP!!!!" , posted Wed 25 Oct 20:59

I have a Trane XE90 upflow natural gas furnace. I'm estimating ten to twelve years old. The burner is not coming on. The small blower motor in the exchanger section comes on, runs for several minutes and then the main blower comes on and they both keep running....but no ignition coil glowing and no burner on. I have cleaned all the condensate hoses, flushed them with hot water and the electronic air cleaner on the return side is spotless. Any help appreciated.

mollydodger

Replies:

mollydodger

70.246.135.239

"More info!!! Still need helllllppp!!" , posted Wed 25 Oct 21:24

I checked continuity on to switches. One is located low and looks like it goes into the heat exchanger. It has two yellow leads. I pulled the leads off and checked across the two poles. Good continuity.The other swtch is high and is directly above the glow igniter. It also has two yellow leads and tests good with the leads off of it. I checked voltage at the black and white wires going to the igniter. When the furnace first strts its cycle, I get 120 volts. Now heres the good part. I turned the unit on. The small blower is running. I took my gas grill lighter and held it where the igniter is and WALLA!!! the burner came on. Shortly afterwards the main blower came on and it has been running for about fiften minutes. I am guessing I have a bad igniter. Please let me know your thoughts.

mollydodger

acefurnacefxr

70.226.28.171

"Re(1):More info!!! Still need helllllppp!!" , posted Thu 26 Oct 07:00

You need a new ignitor, DO NOT LIGHT THE FURNACE WITH ANY DEVICE OTHER THEN WHAT ITS INTENTED TO BE LIT BY.

My spelling sucks thats why I am not a teacher.
22 years of running HVAC service calls Man I have seen it all.
I belong to a union
I also belong to a gym a campground and Triple A.

I may tell you whats wrong but its my job to fix it not yours.

mollydodger

70.246.135.239

"Re(2):More info!!! Still need helllllppp!!" , posted Sun 5 Nov 20:30

Thanks everyone. It was the igniter.

mollydodger

mollydodger

70.246.135.239

"Re(2):More info!!! Still need helllllppp!!" , posted Sun 5 Nov 20:29

mollydodger

mollydodger

70.246.135.239

"still more info please help!!" , posted Wed 25 Oct 22:01

After all the stuff in the above two posts the furnace ran until it reached the temp set on the digital thermostat. After being off a few minutes it started to cycle on. As it started up the small blower moter came on. After a few minutes the main blower came on. NO BURNER!!!! It continues to run, with both blowers on and no flame. The igniter never glows. All help appreciated!!

mollydodger

callmestu

24.3.190.28

"Re(1):still more info please help!!" , posted Wed 25 Oct 23:54

hi,
i'm not a seasoned expert, i've installed my own system but i'm also here looking for help.

however, i do work in a technical field and here we are looking at points of failure.
you have narrowed it down to the ignitor, so it must be either the ignitor itself (likely because of it's age) or the board that controls it, it the connections between them.

boards aren't supposed to go bad, and are expensive. test that the leads to the ignitor are energized when the furnace is on, this will be a 120v source.
if that's the case then go buy a new ignitor.

that's my thought.
googluck
chris