Question about Mr. Heater MHU45LP

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Heater will not ignite

Hi I have a MHU45LP and it worked fine. But now it will not ignite I changed the igniter, flame sensor and even swaped the board out. The gas comes on and still no heat unless I lite it myself. Gives 2 flashes which means no flame detected, and I already know that. Q: How much volts should I have at the igniters?
Any help in this matter would surely save my hairline.

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  • Anonymous Mar 10, 2008

    I have identical issue. I have troubleshot it back to the board as well. I ordered on online today as I have not yet located my original invoice (unit is 8 months old). I will pursue reimbursement for board.

  • Anonymous Mar 18, 2008

    same exact problem.

  • Pnatrick Apr 11, 2008

    same problem but i have the 75 unit

  • shaun35 Dec 06, 2008

    did changing the board work mine is doing the same thing and they are sending me a board


2 Answers

Thanks, I called the manufacurer and they told me it was most likely the board which was not igniting flame. They are sending me a new one. I will see if that does the trick. Thanks for your help.

Posted on Mar 04, 2008

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The igniter should have 120v if it is Hot Surface Igniter (HSI). You may be having a problem with gas pressures. Possible transformer problem also if you changed that with other parts.

Posted on Mar 04, 2008

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