When thermostats go bad

What do you do when the air conditioner or heater refuses to turn on?

• Look at the thermostat to see if the wiring has failed. The wires are supposed to send a message to the heater and air conditioner from the thermostat, telling them to turn on or off. But if they fail, they don’t send the message.

Wire malfunctions also can be to blame for another problem – the system that won’t shut off. If it keeps running and running for no obvious purpose, turn the thermostat to “off.” If the system continues to run, check the wiring.

• Don’t believe the thermostat is accurate? Match it with a thermometer to gauge its accuracy. If it’s off by more than a degree, you can no longer trust it to do its job.

• Another bad sign: The thermostat doesn’t respond when you raise or lower it. Give it two minutes to kick in. If it still doesn’t respond, you probably need a new thermostat.

• We saved the easiest, cheapest fix for last: Check the batteries if the thermostat won’t work. Batteries usually wear out long before the thermostat.


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