If you’ve ever dealt with a heat pump short-cycling, you know just how frustrating this issue can be. When your unit constantly switches on and off, your home never reaches the temperature you set on your thermostat. Plus, you’ll be paying more in energy bills for an uncomfortable home. Learn what short-cycling is, what it means if your unit is short-cycling, and when to contact an HVAC professional to get this common HVAC problem fixed for good.
What Is Heat Pump Short Cycling?
It’s normal for a heat pump to cycle on and off throughout the day when it’s set to a certain temperature or to “auto.” However, if you notice that your unit is frequently turning off and on, yet never seems to reach the temperature you set on the thermostat, it means the unit is short-cycling.
Short-cycling means the HVAC unit is unable to complete a full heating or cooling cycle. A normally functioning heat pump may cycle a few times an hour, while a short-cycling unit will turn off and on every few minutes. A heat pump cycling on and off results in poor temperature control and increased energy bills. It also puts excess strain on the components in the heat pump, meaning you may be forced to pay for HVAC replacement or repair sooner than necessary.
Common Causes of a Short-Cycling Heat Pump
Here are some common heat pump issues that can lead to short cycling.
Air filter problems
One of the most common causes of a short-cycling heat pump is also one of the easiest to fix. Heat pumps have air filters that protect the system from dust and other particulates, ensuring that nothing enters the system that could damage it. As these filters do their job, they become clogged and dirty over time.
If your heat pump is short-cycling, check your air filter first. A clogged filter restricts airflow to your unit, causing it to work harder to heat and cool your home, and can lead to an overheated motor or compressor, resulting in short cycling. For best results, change your air filters every two to three months.
Refrigerant leaks
Refrigerant is a chemical used to cool the air that your heat pump pushes into your home during hot days. If your system is leaking refrigerant, it means the unit has to work harder to cool the same amount of air. Over time, this leads to excess wear on the components and overheating, which causes your heat pump to short-cycle.
While refrigerant issues may seem similar to heat pump water leaks, they indicate a more serious problem. Refrigerants are hazardous to handle without proper training and tools, so it’s recommended to contact an HVAC repair professional if you suspect your unit has a refrigerant leak.
Incorrect system size
Another common cause of short-cycling is a system that‘s the wrong size for the space. If your heat pump is too small for your home, it must work significantly harder to cool and heat the space, leading to component wear, frequent cycling, and a shorter HVAC system lifespan. A system that’s too large, on the other hand, reaches the set temperature too quickly, causing it to constantly shut on and off.
When choosing a new heat pump, work with a pro to avoid issues caused by incorrect system sizing. Your HVAC technician can perform Manual J calculations to determine the appropriate system size for your space, protecting you from short-cycling and other HVAC issues.
Electrical malfunctions
Your heat pump relies on electrical connections to supply the unit with power and stay in sync with your thermostat. If these connections become loose, corroded, or damaged, the intermittent power can lead to issues like short-cycling. Heat pumps use high voltage, so it’s important to leave electrical repairs to the professionals.
Aging system
HVAC systems typically last 10 to 15 years with proper maintenance. If your unit is aging, its internal components are likely worn out and inefficient. This can lead to short cycling and reduced energy efficiency. If your system is reaching the end of its lifespan and having short-cycling issues, it may be time to consider heat pump replacement.
Why Is Your Heat Pump Short-Cycling in Heat Mode?
Is your heat pump short-cycling in heat mode? Part of the air cooling process involves removing moisture from the air with evaporator coils. However, if your unit has a failing blower motor, low refrigerant, or a clogged air filter, these filters can freeze, preventing them from removing humidity.
If you continue to run a heat pump with frozen evaporator coils, it can cause the system to overheat, leading to a pattern of short cycling. While you can address frozen coils yourself by switching the system off and allowing it to thaw for 24 hours, this may not address the root cause. To fix a heat pump for good, contact a qualified HVAC professional for help.
Troubleshooting Steps To Fix a Heat Pump Cycling On and Off
Follow this simple troubleshooting process to address your heat pump short cycling issue yourself:
- Step one: Check your heat pump’s air filter. If it’s visibly clogged or dirty, replace it or clean it according to the manufacturer’s instructions.
- Step two: Confirm that your thermostat is set correctly and has working batteries or a good electrical connection.
- Step three: Confirm that your heat pump’s outdoor unit is clean and clear of obstructions.
- Step four: If the above steps don’t fix the issue, contact an HVAC technician for a professional inspection.
When To Schedule Professional Heat Pump Repair
If you can’t fix your heat pump's short cycling problem yourself, don’t stress. If you need professional heat pump repair services in Warner Robins, Bonaire, and the surrounding communities, the team at Ricky Heath has you covered. While simple fixes can sometimes resolve short-cycling, any issues involving refrigerant, electrical connections, or components of the heat pump should be left to the experts. They have the tools and training needed to keep you and your system safe.
Contact Ricky Heath for Home Comfort You Can Count On
Don’t let a malfunctioning heat pump put a damper on your day. If you’re tired of hearing your unit constantly switching off and on with no noticeable difference in your home’s comfort, Ricky Heath Plumbing, Heating, & Cooling is ready to help. Whether your heat pump needs a quick fix, in-depth repairs, or a complete replacement, you can count on us to deliver exceptional customer service and quality results. Contact us to schedule a heat pump service appointment today.
