When you find that your furnace or air conditioner isn’t working properly, you might immediately have an anxiety attack. Will you freeze in the winter? Or roast in the summer?
Don’t panic.
There are a few simple troubleshooting tricks you can try before calling a local heating and cooling professional.
First, check your air filters. Are they dirty? Dirty filters can reduce the flow of air through your system. You might also want to check the hoses that connect to your HVAC system—make sure everything is correctly plugged in and that there are no holes.
If all looks fine at this point, save a call to a professional by checking for some of the following common thermostat issues:
- Are the batteries dead? It’s common to ignore this simple problem.
- Does it need cleaning? Dust can accumulate throughout the heating or cooling season. With care, use a soft brush or the brush attachment on a vacuum to clean the thermostat. Wipe metal strips with a soft cloth.
- Is there corrosion? You can use an electronic contact cleaner to remove any corrosion. If the thermostat is old or outdated, it’s probably best to replace it.
- Is it in a poor location, such as in direct sunlight? If so, it may register at a higher temperature than the rest of house. If the thermostat is in an interior hallway, it might also register higher than in rooms surrounded by outside walls. If near doors to the outside, it will naturally register at a lower temperature than in the remainder of the house. In addition, make sure the thermostat is located about 5 feet above the floor.
- Is it level? If the thermostat is mechanical, it won’t work properly if crooked. You can’t always determine if something is level just by its appearance. Check with a small torpedo level to make sure.
- Is the fan button turned on when the HVAC system is set on auto? If so, the fan will only run when the HVAC system is running.
- Does the anticipator need adjusting? Look just inside the thermostat door for a small metal tab. This is known as the anticipator, which may need adjusting if the system frequently turns on and off.
- Is it set to a proper temperature? If it’s set too high in the summer, the A/C won’t work because the house temperature might actually be lower than the thermostat setting. Conversely, if it’s set lower than the house temperature in the winter, the furnace won’t turn on.
- Is there a short? A loose connection in the wires will cause a thermostat to function improperly or not at all. Before you attempt any inspection of the wiring, turn off all power to the system. Then check the connection for shorts or bare or touching wires.
- Is it set to the right function? If your thermostat is set to “Cool” when using the A/C or “Heat” when using the furnace, you won’t get the cooling from the A/C or the heat from the furnace.
- Is your furnace in a “lockout” state? Some furnaces are equipped with a safety device that will shut down if lockout occurs. You could be left with intermittent heat in this situation. Turn off the electricity to the furnace and wait several minutes before turning it back on.
If all else fails, don’t hesitate to contact your local heating and cooling repair professional.
