Is your system turning on and off, over and over again, in rapid succession? HVAC short cycling is a serious problem that wastes energy and wears out the unit prematurely. There are a number of potential causes. Here’s what to look for and how to prevent it.

  • Air filter. If your filter is clogged, air can’t flow properly through your system. The unit has to work harder to heat or cool your home, and HVAC short cycling can result. To prevent this, change the filter regularly. If it’s gray and opaque, it’s due for replacement.
  • Evaporator coil. If your evaporator coil is frozen, it prevents heat exchange within your system, which can lead to short cycling. This might be caused by debris in your outdoor unit, which can easily be cleared away. However, it might also indicate a refrigerant leak, which is a more serious problem requiring the attention of your HVAC technician.
  • Low-pressure control switch. If there’s not a refrigerant leak, there may be a problem with the low-pressure control switch, which regulates refrigerant pressure. Poor refrigerant pressure can have the same effect as too little refrigerant, resulting in short cycling. Call your HVAC technician to replace the switch.
  • Thermostat placement. If the thermostat is in the direct path of one of your registers, it can mess with the temperature readings, causing it to turn off too soon. Place your thermostat in a convenient, central location away from vents or registers.
  • Sizing. One of the most common causes of HVAC short cycling is the unit being too big for your home. Blasting too much air all at once can make your thermostat think your home has reached the set temperature before it actually has, causing it to turn off. This can also result in disparate temperatures across rooms and feelings of clamminess and discomfort. If your system is the wrong size, you’ll need a new one that can handle your heating or cooling load properly.

If you’re experiencing issues with your HVAC short cycling, contact us at Mowery Heating, Cooling and Plumbing. We serve all of Indianapolis’ home-comfort needs.