When your heating or air conditioning isn’t working properly, the thermostat is often the last thing you may think to check. It’s important, however, to keep your thermostat in the best condition possible. There are several steps you’ll need to take when testing and tuning your thermostat.
Begin by accurately testing your thermostat. You can do this by taping a thermometer near a wall. You should use a glass thermometer and gently place paper towels under the thermometer so it isn’t directly touching the wall. If it is directly against a wall this may affect the reading. Once the thermometer is correctly attached, let your AC or heater run for about 15 minutes. If the reading of the thermometer and the thermostat are off by more than one degree there are several steps you can take to tune your thermostat.
Something as simple as keeping a thermostat clean can make a big difference in how well it works. It’s important to clean it on a regular basis and remove all dust and debris. You can do this by carefully removing the thermostat cover. Use a soft cloth to gently clean coils and other inside parts. Don’t use a vacuum cleaner or any other type of strong suction.
A thermostat may not work as well as it should because it’s in a bad location. Make sure it’s not near a heat source such as a lamp or a television. It should never be placed in direct sunlight, near an air vent, or in or near the kitchen. To receive the most accurate reading, the ideal location is on an inside wall, near the center of your home.
If these relatively simple tips to clean and locate correctly don’t work, it may be time to get more technical. Use a small screwdriver to tighten the calibration screw. This particular component is usually located in a curled part of the metal inside the thermostat. After looking at the metal you’ll be able to determine what size screwdriver you’ll need. Turn the screw slowly back and forth until contacts are clearly open. Then slowly turn the screw back so that the contacts close again. This process should reset the contacts.
When your furnace or AC cycles off and on too much or too little, you might want to check the anticipator. This is normally a flat pointer made of metal. If your heat is turning on and off too frequently, move the anticipator just a bit higher. If it’s too seldom, move it slightly lower. Wait about an hour to see if this works.
Finally, it’s important to note that sometimes a mercury vial will need straightening. This, however, could be dangerous since mercury should never touch human skin. If the previous tips haven’t worked it may be time to contact a professional to have your thermostat repaired or replaced.