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I have a honeywell gas heater hanging from the ceiling in my shop Model # uhpa175ae-3 Serial # 6396j03508 The exhaust fan starts, the flame lights and finally the main fan kicks in. Quite often, as soon as the main fan begins to turn you can hear a relay begin to click and the fan surges and stops over and over again, until presumably the overlimit switch kicks in, turns off the flame and tries the process over again. Can you help me?

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HI clean the flame sensor check out the pressure switch jump this out to see if it lights clean sensor on fan control might be dirty clean heater with air line burners heat exchanger then it might be your limit switch but this help doing this other work first

Posted on Feb 01, 2010

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