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Intertherm Furnace Will not stay on

I have had to hit the reset button for it to heat. Now, I have a blinking light that indicates "Limit Circuit Open or External Load on W." What does this mean?

I have had several problems with this furnace. Every year it seems we have to replace a part or two.

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  • Keith Miller
    Keith Miller May 11, 2010

    limit switch can be high temp in fire box due to low air flow dirty air filter will the blower fan run


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Your furnace is likely getting too hot check your filter. make sure the fan is running. if you have weak air flow you may have a blocked heat transfer coil. you should have your heating and cooling system serviced yearly by a qualified company to inspect and test equipment.

Posted on Jan 05, 2009

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SOURCE: Intertherm Furnace Will not stay on

dirty air filter low air flow causing high temp in fire box to trip limit switch or fan motor

Posted on Jan 07, 2009

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Posted on Jan 02, 2017

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2 Answers

Intertherm Furnace Will not stay on

possible dirty air filter low air flow causing high temp in fire box to trip limit switch or fan motor is bad hope this help let me know if you if this solved problem I may need more info

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