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Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 6022
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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Replaced the AH control BOARD ON A M# NFCP3600A1, S# L9724

Customer Question

replaced the AH control BOARD ON A M# ***** S# ***** 14589. when i turn the disconnect on the blower comes on and will not turn off. removed all low voltage wiring from the LV terminals and it continues to run. checked the overlords on the HS and they are good. heat relay coils all ohm out at .530 ohms +- 5%. all heat strips cycle when called for. have replaced two boards and the same thing happens.
JA: Did you double-check the thermostat's settings? And what about the filters?
Customer: Replaced thermostat and filter. all low voltage has been removed from unit control board.
JA: Do you plan on doing the work yourself?
Customer: yes. i am a HVAC Tech of 40 years.
JA: Anything else we should know to help you best?
Customer: i have unplugged all the heat relays and tried it without any low voltage to the relays and the blower continues to run.
Submitted: 11 months ago.
Category: HVAC
Expert:  BillyHvac replied 11 months ago.

can you please tell me the board number you are using?

Customer: replied 11 months ago.
Customer: replied 11 months ago.
i sent my contact info but haVE NOT HEARD FROM BillyHvac
Customer: replied 11 months ago.
far i am not satisfied with what i have been charged for. Thought i was getting a phone call and now i have been pawned off to someone else and still do no shave an answer for my problem. so far not good service!