I have a luxaire gas furnace and the heat keeps cutting off. When it cuts off, I have a red light that flashes 4 times. What does this mean?

Look for a legend that details status codes. Could be on the inside of a panel or on the circuit board housing.

Usually it means this for a Luxair

"4 RED FLASHES: This indicates that a primary or auxiliary limit switch has opened its normally closed contacts. The control will operate the supply air blower and inducer. This condition may be caused by: dirty filter, improperly sized duct system, incorrect blower speed setting, incorrect firing rate or faulty blower motor. Also, this fault code could be caused by a blown fuse located on the control board."

Quote:

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Originally Posted by hvac1000

Usually it means this for a Luxair

"4 RED FLASHES: This indicates that a primary or auxiliary limit switch has opened its normally closed contacts. The control will operate the supply air blower and inducer. This condition may be caused by: dirty filter, improperly sized duct system, incorrect blower speed setting, incorrect firing rate or faulty blower motor. Also, this fault code could be caused by a blown fuse located on the control board."

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Which fuse do they have on the board? How about the limit switch being bad?

dobiefloyd

If you are asking a question please post your own question.

If you are trying to help with a answer please answer the question but do not ask more questions unless it is your post.

Just trying to prevent some confusion here.

Error code 4 says limit switch open. I changed the filter but the same thing keeps happening. I don't think it's a faulty blower motor and the return size has been fine since the intsallatio2 years ago. Any other suggestions ?

Quote:

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Originally Posted by hvac1000

Usually it means this for a Luxair

"4 RED FLASHES: This indicates that a primary or auxiliary limit switch has opened its normally closed contacts. The control will operate the supply air blower and inducer. This condition may be caused by: dirty filter, improperly sized duct system, incorrect blower speed setting, incorrect firing rate or faulty blower motor. Also, this fault code could be caused by a blown fuse located on the control board."

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You can test the limit switches by jumpering them or look in the center of the switch for a reset button if so equipped. NOTE: if the unit starts to function while testing any switch or control DO NOT allow the unit to operate without replacing the part that is defective first. Something caused the unit or switch to malfunction and that needs to be corrected also.