Common Reasons Why Your HVAC System Won’t Stay On

Common Reasons Why Your HVAC System Won’t Stay On

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If your HVAC system won’t stay on this winter, maintaining warm temperatures and keeping the home comfortable will be a significant challenge. For Atlanta area homeowners facing this heating problem, Estes Services can help. Our heating professionals share common reasons why your HVAC system won’t stay on as well as what needs to be done to correct these issues.

1. Short Cycling

Short cycling is an HVAC term that describes a heating or cooling unit that shuts down shortly after starting a heating or cooling cycle. The normal length of a heating cycle is about 10 to 15 minutes, though the furnace or heat pump may run longer when it’s extremely cold outside. Anytime the system shuts down in about half this time or less, it is short cycling.

Short cycling is a big problem you’ll want to fix fast, as it not only causes comfort issues, but allows the heating system to waste energy and places the system components under increased stress. Your heating bills will be more expensive and your system more likely to suffer breakdowns, not to mention a need for early system replacement.

  • If your thermostat isn’t reading temperatures properly or communicating correctly with the furnace or heat pump, this can cause short cycling. Make sure the thermostat has fresh batteries. You can clean its sensors by removing the faceplate and using a soft brush or can of compressed air. Also, make sure all wiring connections are tight, and use a screwdriver to tighten any loose connections you find.
  • Short cycling can also be caused by a dirty air filter, which causes the system to overheat and shut down early for safety. Check your filter and replace it if it is full of contaminants. Also, make sure it is installed in the correct position and is the correct size, as filter errors can restrict air movement through the system which leads to overheating.
  • If you use a heat pump to heat your home, a dirty outdoor unit could be restricting operation enough to cause overheating and short cycling. Clean away any debris trapped up against the unit’s fins. Pull out vegetation growing up against the unit. Trim back bushes and branches close to the heat pump. Remove outdoor items stored up against the unit and in the immediate surrounding areas – always leave at least two feet of free space surrounding your heat pump.

Some other reasons your HVAC system won’t stay on due to short cycling are incorrect sizing, frozen coils, low refrigerant due to a leak, a faulty compressor, or malfunctioning control board. These issues require the help of a professional HVAC technician to fix through heating repair.

2. Bad Thermostat

A bad thermostat could be reading temperatures incorrectly, causing it to send the wrong instructions to your heating unit, which is why your HVAC system won’t stay on. Cleaning the thermostat as mentioned above may solve this problem if dirty sensors or loose wiring are causing this mishap. If the thermostat’s calibration is off, your HVAC technician can correct this issue. The thermostat may be bad and due for a replacement, which can be handled by your HVAC technician as well.

3. Faulty Thermocouple

Furnace systems have a heat sensor that works to close the gas valve if the furnace does not ignite. The sensor’s thermocouple can malfunction, restricting its ability to detect heat. If this happens, the sensor will shut off the gas valve for safety reasons and your HVAC system won’t stay on. This issue can be diagnosed by an HVAC professional, and the part can be replaced if needed to restore furnace operation.

4. Blower Motor Problems

A furnace or heat pump uses a blower to circulate heated air from the unit into your home. The blower motor could lose power due to a bad fan relay or the belt may slip or break, preventing the fan from running properly. If the blower is not working correctly, the system will shut down to prevent overheating, which is why your HVAC system won’t stay on. Heating repair can diagnose and solve these issues.

Contact Estes Services for Heating Repair in Atlanta, Georgia

If your HVAC system won’t stay on and you are unable to fix this issue through troubleshooting, turn to Estes Services for help. Our heating and air conditioning system repair professionals service furnaces and heat pumps in homes throughout the Atlanta, GA area. Contact us today to schedule service