HVAC systems are designed to cycle on and off to maintain a comfortable indoor temperature. However, when they cycle too frequently, it can lead to problems like shortened equipment life, higher energy bills, and even frozen pipes. So, what causes HVAC short cycling, and how can you prevent it?
Your heat pump is responsible for keeping your home comfortable all year long. Your equipment might have to work hard to combat outside conditions depending on where you live. If your system is short cycling, however, your home won’t maintain a comfortable temperature. There are many possible reasons for HVAC short cycling. One common cause is a dirty filter, which can restrict airflow and cause the system to turn on and off more frequently. Other causes can include a malfunctioning thermostat or a unit that is incorrectly sized for your living space. Let’s take a closer at heat pump short cycling.
Dirty Air Filter
A dirty air filter can cause a heat pump to short cycle. Your air filter is responsible for catching and trapping airborne contaminants such as dirt, dust, pollen, and other allergens and debris. This helps to prevent your system from circulating dirty air around your home. However, when the filter gets too dirty, it won’t let enough air flow through to keep the heat pump running properly. This can cause the heat pump to short cycle and turn on and off more often than it should. Short cycling can lead to problems like overheating. Your air filters should be changed at least every three months. However, you might need more frequent checks depending on several factors.
Malfunctioning Thermostat
Another common problem for your heat pump to short cycle is thermostat malfunction. The thermostat is an often overlooked component of your HVAC system. However, as the director of your heating and cooling operations, your thermostat serves an important role. Your device detects indoor temperatures and then calls for heating or cooling based on your desired temperature setting. If the batteries or wiring in the thermostat have gone bad, the internal controls won’t be able to control your heat pump properly.
Additionally, a failing internal thermometer won’t detect an accurate indoor temperature properly. The thermostat could cause your heat pump to turn on and off at irregular intervals in any of these scenarios. Your thermostat should last about 10 years but will eventually begin to wear out and will need to be replaced to avoid issues with short cycling.
Wrong Unit Size
No matter if your equipment is brand new or has been in your house for a while, incorrect sizing could create a short cycling problem. A heat pump that isn’t a good fit will work harder to maintain a comfortable temperature in your home. Short cycling is a symptom of a heat pump that is too small for your home. The equipment must work harder and more frequently to keep up with the set temperature. Not only will this increase your energy bills and make your home less efficient, but it will also increase the likelihood of a system failure. As a result of the short cycling, the unit will experience more wear and tear and develop more issues over time.
If you’re experiencing HVAC short cycling, the best thing to do is to identify the cause and take steps to correct it. In most cases, this can be done by cleaning or replacing the filter, checking the thermostat, and getting professional advice about equipment sizing. Proper care and maintenance of your HVAC system will help prevent many issues that might arise over time. However, if you notice short-cycling as a sudden problem, you may need to consult with a qualified HVAC technician for a solution.
