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Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 6022
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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I have a Trane XE78. It started giving me problem, i.e., no

Customer Question

Customer: My name is***** have a Trane XE78. It started giving me problem, i.e., no heat, fan running. I called for repairman. He came and clean the sensor. After 18 hour, the problem came back. I called the serviceman. He said that I should turn off and on the electricity to the furnance, That worked for another 18 hours. When I called again, he said that the control board need to be replaced. He can get the board and install it for $525. I ordered the control board online and replaced it. The problem is not solved. What should I do? thank yo
JA: Thanks. Can you give me any more details about your issue?
Customer: When I turn the heater on, the spark turns a couple of time, but the furnance does not start, then the blower start working and giving cold air. Dring that time, I get "Flashig Fast" signal, but when the fan starts I get two flashes for a while and then nothing.
JA: OK got it. Last thing — JustAnswer charges a fee (generally around $18) to post your type of question to HVAC Experts (you only pay if satisfied). There are a couple customers ahead of you. Are you willing to wait a bit?
Customer: sre.
JA: OK. Now I'm going to take you to a page to place a secure deposit with JustAnswer. Don't worry, this chat is saved. After that, we will finish helping you.
Submitted: 1 year ago.
Category: HVAC
Expert:  airheatman replied 1 year ago.

Please give me complete model on furnace and tell me what exactly happens on call for heat.Also does fan run non stop when not calling for heat?

Customer: replied 1 year ago.
It is Trane XE78 Serial No TID100C948A1. Model no G39534650 . I replaced the original control board with model CNT03797.
Customer: replied 1 year ago.
When I turn the heater ob
Expert:  airheatman replied 1 year ago.

Let me see if I have access to wiring diagram on furnace

Customer: replied 1 year ago.
Let us woe
Customer: replied 1 year ago.
Let us work on line
Expert:  airheatman replied 1 year ago.

I can not find manual on the furnace so I am going to open to other experts who may be able to assist with better accuracy rather that just tell you to start changing parts which would be less than professional and a guess at best without doing some troubleshooting.Please wait to see if someone is available more familiar with your unit.Replying will send this back to my desk and delay the process of getting an answer to your question.

Customer: replied 1 year ago.
I will not wait 24 hours. You have asked me questions withot providing any answer. You are not going to charge me anything beyond the $5. Period.