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Blower Will Not Stop

Name: Dumitru  City:

Question: When the temerature in the house reaches the level set on the thermostat, the furnace starts blowing cold air insted of stoping. What could be the problem?

Name: Rich | Date: January 6, 2005, 9:55
Answer: On a modern furnace this can be caused by a dirty air filter. The plugged filter causes the furnace to over-heat and the "limit switch" opens. The computer then tells the blower to run until the limit switch closes again. Look for a flashing light and the legend that refers to it.Sometimes the limit gets stuck open. If it is the limit, you'll need a pro. Good luck.

Name: Rich | Date: January 6, 2005, 9:59
Answer: P.S. Since you are getting heat, that means that the limit does close eventually. Check the filter (change monthly).