How to Troubleshoot a White-Rodgers Thermostat

White-Rodgers, part of Emerson Electric Co., has been manufacturing thermostats since 1936. It was founded by a group of Emerson engineers and was eventually acquired by Emerson in 1961. Problems with the thermostats are generally related to no heat or cooling. Continual running of the heating, ventilation and air conditioning equipment is another possible problem and is often due to a short.

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Split systems may have a power switch for the outside unit.

Step 1

Verify that the household power supply hasn't been interrupted if there's no heating or cooling. Check the home's breaker panel and look for tripped breakers or blown fuses. Check to see that the HVAC equipment is switched on. Split systems may have a power switch outside for the outside unit. The blower, furnace and air conditioning need power to function. Light the pilot if there's no heat.

Step 2

Set the system switch to "Heat" to perform some diagnostics on the heat function of the thermostat. Raise the thermostat's temperature above the ambient temperature. You should hear a click. If you don't hear a click, reset the thermostat. Open the thermostat cover and remove the wires from terminals R and C, and take out the batteries for two minutes. Replace them. Raise the thermostat's temperature above the ambient temperature again and listen for a click again. If you don't hear it, replace the thermostat. If you do hear a click but the heat fails to function, have the furnace side of the HVAC system serviced.

Step 3

Set the system switch to "Cool" to perform some diagnostics on the cooling function of the thermostat. Lower the thermostat's temperature below the ambient temperature. You should hear a click. If you don't, reset the thermostat. Open the thermostat cover and remove the wires from terminals R and C, and take out the batteries for two minutes. Replace them. Lower the thermostat's temperature below the ambient temperature again and listen for a click again. If you don't hear a click, replace the thermostat. If you do hear a click but the cold fails to function, have the air conditioning side of the HVAC system serviced.

Step 4

Open the cover and look for shorts if the HVAC system runs continually. Check each wire -- no bare wire should protrude from the block. Also, the fan switch may be set to "Fan" rather than "Auto."