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Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 8769
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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I have a TRANE model number BLU080F924B1 furnace. The pilot

Customer Question

Hi. I have a TRANE model number BLU080F924B1 furnace. The pilot won't turn on at all. I hear the click when I turn it on but nothing happens.
Submitted: 2 years ago.
Category: HVAC
Expert:  Phil replied 2 years ago.


If you can take a well focused, well lit, close up photo of the wiring diagram glued inside the blower service door, I can mark it up with trouble shooting directions. Include a photo of the printed circuit card in the same compartment where the thermostat wires attach

You will need a multi meter do do a few tests.

Use the paper clip icon at the right end of the tool bar above to attach the pictures.

We can go from there.

Customer: replied 2 years ago.
Unfortunately I can see where said diagram was glued but no longer is.
Customer: replied 2 years ago.
There is also no circuit card
Expert:  Phil replied 2 years ago.

Hello again, tell me please about how old the furnace may be too old to have a printed circuit card in it, and also too told to have a wiring diagram available on the web.

Let me know about that, I will see what I can find on the web its not too old. There is another issue with old furnaces, they leak carbon monoxide in many cases, that can ruin a persons health and is even more damaging to children.

We can go from there.

Customer: replied 2 years ago.
It appears to have been manufactured in 1985
Expert:  Phil replied 2 years ago.

Thanks, ***** ***** about the time they began using printed circuit cards.

Look under the burners and use a long handled spoon to drag out the rust under each burner, tell me if there are any larger chunks of rust or a lot of rust and tell me if the flames in any of the burners change when the blower starts... look very very carefully for any change in the flames... that will tell us a lot.


Customer: replied 2 years ago.
There is no flame. Sorry I wasn't clear. The pilot won't light. When I turn the thermostat on. I hear the click but nothing happens.
Expert:  Phil replied 2 years ago.

Hello again,

The cause of failed ignition is generally a bad spark or glow plug igniiter module, or a bad gas valve. If you can follow the wires that attach to the pilot light back to where they came from, that will be the ignition module. It will have a brand name and model number on it in most cases.

Then there is a chance we can order you a new one... there is about a 50% chance that will work.

Without a wiring diagram I am at a loss on how to coach you any more effectively than that.


Important note:

It is common that older furnaces develop cracks in their heat exchangers, and that ruins the lives of many people... with older furnaces a few cursory checks are *vital... if you find large chunks of rust under the burners, the heat exchanger is most likely cracked or soon will be cracked and a serious hazard to your health... in that case you will not want to spend any money on repairs and will want to replace the furnace.