Does your HVAC system run for a minute or two, turn off, then run for another minute or two? This problem is called short cycling, and it’s a serious issue that needs to be resolved. It can lead to system damage and high energy bills.
Many things can cause short cycling, and it can be difficult to determine the exact cause. Here are some of the most commonly experienced causes of short cycling:
Improper thermostat placement.
Your home’s thermostat should be located centrally and not near air vents or windows. When a thermostat is located near an air vent, it could determine that a room is cooler than it actually is. When a thermostat is placed near a window, heat from the sun could heat up the thermostat, making it think your home is warmer than it is. It’s also possible that your thermostat is correctly located but is malfunctioning.
Dirty air filter.
No HVAC problem is more common than a dirty air filter. Dirty filters prevent air from flowing correctly and can cause the condenser coils to freeze up. When this happens, the air conditioner could shut off before it has cooled your home to the temperature you set. Then, the thermostat would notice that the temperature isn’t as it should be and turn the system back on, causing improper cycling.
Refrigerant leak.
When a system is low on refrigerant, it can short cycle because it isn’t operating properly. This can cause the coils to freeze, turning off the AC unit. Refrigerant is not something that should be used up or become low, so a system that has lost refrigerant has a leak that needs to be professionally repaired, then the refrigerant can be restored to its proper level.
Dirty condenser coils.
Coils are part of the outside AC unit and are responsible for doing away with heat by releasing it into the outside air. When condenser coils are dirty, they must work harder than necessary to do their job. This causes the system to overheat and shut itself down. Cleaning products are available at discount stores and home centers, but every air conditioning system needs professional cleaning and maintenance every year.
A system that’s too large for your home.
If short cycling is a problem you’ve had since the system was installed, your HVAC system may be too large for your home. Oversized units cool the home quickly and then turn off. This may seem beneficial, but the frequent cycling to maintain an optimal temperature can lead to uneven cooling and higher utility bills.
There are other causes of short cycling. An HVAC technician can determine the true cause of your system problem and implement a solution that’s sure to work.