Trane XE90 Furnace Fails to Ignite

[Jefferson]

I have a Trane XE90 natural gas furnace. When heat is called for, the Power Vent Fan starts, the ignitor goes on and turns orange, I hear a click calling for the gas, but the furnace does not light. After the furnace fails to ignite, the unit continues to operate as though it had ignited and blows cold air throughout the house. However, if I gently blow toward the ignitor after it turns orange, the furnace lights up and warm air is forced through the system.

I attempted to troubleshoot the problem by performing the following steps. First, I removed the front metal panels and cleaned the inside of the furnace to remove any dust and other collected particles in the unit. Next, I replaced the air filter with a brand new filter. This failed to solve the issue. Next, I replaced the ignitor, but the unit still failed to ignite without the gentle blowing. I then checked the tubing going to the pressure switch and the entire exhaust line for obstructions. I was unable to find any obstructions in either line. Finally, I reset the entire unit following the instructions listed on the furnace panel. This too failed to solve the issue.

I do not want to run to my basement and blow through the grate in the furnace panel every time my thermostat calls for heat. Can you please help me resolve this issue.

 

[user 4883]

Not sure where you obtained a new ignitor, Trane parts are highly guarded and universal parts sometimes are not the best.
However, it does sound like you need to clean or replace the flame sensor. If the ignitor ohm'd out over 100 then it was bad otherwise your just guessing and that can get expensive.

 

[Jefferson]

I replaced the ignitor with an original Trane replacement. I cleaned the flame sensor and still no luck. Any other ideas?

 

[user 4883]

replace the flame sensor with OEM. Make sure it is in the path of the flame.

 

[Jefferson]

I replaced the flame sensor and this did not work. Then I replaced the gas valve and this did not work either. The only part left is the board. I will try that today. This is frustrating.

 

[Wuzzat?]

if I gently blow toward the ignitor after it turns orange, the furnace lights up and warm air is forced through the system.

At least one problem sounds like the ignitor is not in the way of the incoming gas. I guess you could use a narrow strip of tin foil hanging vertically to make the path of the gas visible.

The money you have spent is a 'sunk cost'. Try to avoid letting this spent money influence your future decisions about how to proceed with this furnace.

 

[AlexL]

Hello. I have exactly the same problem with this furnace. I replace igniter and sensor every season, but flame ignition fails regularly. I haven't replaced hte valve yet, think need to wait with it. What I noted that time from valve click to lockout is very short, nearly 1 second or less. Another words, the igniter turn orange and stays for a while 2 sec, then valve clicks. But by that time the igniter goes off, not leaving enough time for flame ignition. Can you suggest a fix? Is there an adjustment for igniter to stay on longer? Thank you

 

[AlexL]

At least one problem sounds like the ignitor is not in the way of the incoming gas. I guess you could use a narrow strip of tin foil hanging vertically to make the path of the gas visible.

The money you have spent is a 'sunk cost'. Try to avoid letting this spent money influence your future decisions about how to proceed with this furnace.

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  Today at 10:41 AM

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• #7

Hello. I have exactly the same problem with this furnace. I replace igniter and sensor every season, but flame ignition fails regularly. I haven't replaced hte valve yet, think need to wait with it. What I noted that time from valve click to lockout is very short, nearly 1 second or less. Another words, the igniter turn orange and stays for a while 2 sec, then valve clicks. But by that time the igniter goes off, not leaving enough time for flame ignition. Can you suggest a fix? Is there an adjustment for igniter to stay on longer? Thank you

 

[mark3885]

Pictures would help

 

[AlexL]

Pictures would help

I have a question , what is the function of this sensor exactly? It seems that it does not affect the length of time for igniter to run hot.
Thank you
Alex

 

[AlexL]

Hello. I have exactly the same problem with this furnace. I replace igniter and sensor every season, but flame ignition fails regularly. I haven't replaced hte valve yet, think need to wait with it. What I noted that time from valve click to lockout is very short, nearly 1 second or less. Another words, the igniter turn orange and stays for a while 2 sec, then valve clicks. But by that time the igniter goes off, not leaving enough time for flame ignition. Can you suggest a fix? Is there an adjustment for igniter to stay on longer? Thank you

Also if anyone can advise on exact function of this sensor. Does it senses the flame that already established or it affects the ignition process, that keeps failing. Usually on cold night (low gas pressure in the system?)

 

[mark3885]

When the power vent turns on, put a lit cigarette or something that has some smoke to see if draws the smoke in . Maybe a problem with the power vent not opening fully to pull the gas over the igniter