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TPA 841 No 36 - 40


TPA 841 No 36 - 40

Lennox Furnace Diagnostic Codes

I need some help figuring out these Lennox furnace diagonostic codes.

What is it you need help understanding? I always thought you were a whiz.

Of course I am. However, I don't get these error codes.

OK, lets get down to the basics. I assume at this point that you have seen the lights, which are located on the access panel.

Yes, I have seen them. There are two lights there.

These buttons are labled with diagnostic codes. There are red codes, that are labeled diagnostic codes one and two.

Go on, I am listening.

The buttons will tell you what is happening with your furnace. You should have a manual that will explain what the codes mean.

Push and hold the main red button, and if both buttons flash once, it means the furnace has normal operation.

Diag one flashing with diag 2 on, means that the limit switch is open. They are supposed to reset on an automatic basis.

OK, I am taking notes on this. You are such a help. Remind me to thank you some time.

No time like the present, but I know how you are, I'll take a raincheck.

Are there any other codes I need to be aware of?

Yes, the final codes that you should write down in your little schoolboy notebook there, is the fact when diag 1 is off, and diag 2 is flashing, it means that the switch controlling the pressure has failed. This is usually do to a blocked condensate drain.

If diag 1 flashes and then diag 2 flashes, this means a failure of the ignition.

The furnace will go into lockout mode. You can reset it by turning off the power.

OK, I think I lost the manual. So I am really happy to hear what the codes mean.

Yes, you were right to come to me. It is always nice to know what things mean.

Yes, from what you told me about Lennox furnace diagnostic codes, I think my furnace actually is operating normally.

Good to hear friend, now how about that reward?



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