Question about Mr. Heater Natural Gas Garage Heater - 45,000 BTU

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I have a mr heater 75000 with a 4 flash blink code. the heater is brand new, only worked for 3 days. i have bypassed the 2 switches but still cant clear the 4 flash blink code.

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According to the Owners/Installation Manual, the 4 flash blink code indicates that the High Limit or Roll Out Switch is open. This may be caused by a venting problem or high altitude operation. make sure you have the proper pressure to the heater's regulator. For Natural Gas it must be a continuous 7 water column inches.

For further information, I have included a link to your Owners Manual that you can download and print, for future reference.

Hope this helped to solve your problem.

Posted on Mar 22, 2011


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