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4 Common Thermostat Errors and What They Mean.

July 6, 2018

Troubleshoot Your Thermostat

Your thermostat is the brain behind your HVAC system, and it plays an important role in maintaining comfortable temperatures throughout your home. However, when your HVAC system stops working, it’s common to overlook your thermostat as the culprit and not realize that faulty thermostats can lead to more than just temperature inconsistencies — they could even be the reason your system won’t turn on.

The good news is that most thermostat errors are easy to diagnose and repair with the help of the right HVAC specialist. Read below for a few of the most common thermostat errors and how to identify them before calling a service technician.

Before you contact an HVAC professional, check to see whether your breaker has been tripped, a fuse has been blown, or if someone set the temperature incorrectly. You should also verify that your thermostat isn’t out of batteries. These are all problems to troubleshoot yourself before seeking help from a professional.

However, if the thermostat is in fact receiving power, problems may be a sign of a more serious, complicated issue that will require the expertise of a trained HVAC specialist.

Common Thermostat Errors:

1) The Air Conditioner Isn’t Working

If you’re desperately trying to change the temperature and nothing seems to be working, it might be a sign of a thermostat malfunction.

If the thermostat is receiving power, turn off the thermostat breaker and safely remove the cover of the thermostat to look for a buildup of dirt or debris. These may be impairing the device from functioning properly. If you notice soot or grime in your thermostat, carefully remove and clean it with a can of compressed air or soft cloth. Ask a professional for help to prevent any damage to the thermostat or yourself.

2) The Setting and the Room Temperature Don’t Match

If the room temperature and your thermostat reading appear to be inconsistent, get a second opinion by taping a thermometer to your wall. If you notice a serious discrepancy between the readings of the thermostat and thermometer, this might indicate something is wrong with your thermostat.

A buildup of dirt causes inconsistencies in your thermostat reading, so follow the cleaning instructions above before considering any other causes. If dirt or debris aren’t hindering the device, the problem could be with your heat anticipator. The heat anticipator is the part of your thermostat that is responsible for turning off the furnace burners when a room or space is properly heated. Ask a professional for help with checking whether the heat anticipator is functional, stuck, or needs recalibration.

There also might be a difference between the thermostat setting and the room temperature if your thermostat is installed in a bad location. Direct sunlight, cold drafts, fireplaces, open windows, or other heating and cooling sources could impair your thermostat, and relocating it may help with more consistent readings.

3) The Device Doesn’t Turn Off

A thermostat that doesn’t turn on is troublesome, but a thermostat that won’t turn off could be just as bad. If your thermostat is continuously running, it can make your whole house feel uncomfortable — and seriously impact your energy bill.

Again, first check for grime or dirt in your thermostat before continuing to troubleshoot. If your thermostat is clean, the issue could be a poorly calibrated heat anticipator. If this is the case, get a professional HVAC technician to help you lengthen the cooling cycle of your thermostat.

4) The Temperature is Constantly Fluctuating

If your thermostat is constantly switching on and off but never reaches the temperature you want, you might need to reset the system.

In addition, you should check that the thermostat is installed correctly, as this can affect heat regulation. Use a level to see if the thermostat is mounted properly on the wall and check that it is not installed near any doors, windows, or other heating or cooling sources.

Improper heat regulation could also be related to the heat anticipator. If the dial is set to shorter cycles, it could cause the furnace to turn off and on more rapidly. Ask an HVAC technician to troubleshoot and calibrate the anticipator for you if you believe the device is the cause of your issue.

Address Thermostat Problems Immediately

Some issues with thermostats are easy to fix with a simple cleaning, reset, or change of batteries, but more serious issues require the help of a professional. Contact our HVAC specialists at Bob Jenson for help troubleshooting and repairing your thermostat to keep your HVAC system running smoothly.

About The Author

Bob Jenson

For over 45 years, Bob Jenson has been providing quality heating and air services to the San Diego community.

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