Why Does My Heat Pump Short Cycle in Hillsborough, NC?

Short-cycling is when your heat pump turns on and off too quickly instead of completing a full cycle of heating or cooling. This can be quite annoying, and it can create discomfort and confusion in your Hillsborough, NC, home this fall. Here are a few potential reasons your heat pump short cycles:

Thermostat Issues

Since your thermostat controls and issues commands to your heat pump, it may be the ultimate source of the problem rather than the pump itself. Something might be causing the thermostat to read temperatures either inaccurately or at least in a way that does not reflect the true climate in your home.

For example, if you’ve placed your thermostat in an area that receives more sunlight or more chilly breezes than the rest of your home, it may register temperatures that are either lower or higher than those prevailing everywhere else. If it does so, your thermostat can assume those temperatures represent your whole home and will inappropriately either turn on or turn off your heat pump.

Alternatively, there might be a problem with the thermostat’s wiring that causes it to malfunction. In that case, you will need a professional service tech to come examine the device and either repair or replace it for you.

An Improperly Sized Heat Pump

Before installing an HVAC system, a team of service techs should always perform something called a Manual J load calculation. This is a process whereby the team makes note of certain facts about your home and determines its HVAC capacity, choosing a system of a given size based on the result.

If the team took this measurement incorrectly, your heat pump may be either too large or too small for your home. Short-cycling may result in either case.

Refrigerant Leaks

Heat pumps use refrigerant to perform heat transfer. If too much refrigerant somehow leaks out of the system, it may not be able to perform a heating or cooling cycle at all and may shut down prematurely.

Since refrigerant is dangerous, you should never attempt to refill your heat pump on your own. Instead, request assistance from a professional service tech. Service techs typically check refrigerant levels during routine maintenance.

Short-cycling is an irksome problem, but with professional help, it’s resolvable. Call us at Warren-Hay Mechanical for heat pump service in Hillsborough, NC.

Image provided by iStock