We all rely on our HVAC systems to keep our homes comfortable from season to season. However, air conditioners, furnaces, and heat pumps alike are prone to confusing problems that make this difficult. So, why is my heat pump turning on and off?
Your heat pump may be turning on and off because the filter is clogged or there is a refrigerant leak. Short cycling can also happen due to a wiring problem with the thermostat. Otherwise, it may be because of a dirty condenser coil or evaporator coil. Heat pumps can experience such problems when they’re over 15 years old.
Luckily, many of these problems are easy to repair if you hire a licensed HVAC technician. Follow along as we explore why your heat pump keeps turning on and off and highlight the best fixes.
Why Does My Heat Pump Keep Turning On and Off?
1. Clogged Filter
Do you regularly replace your air filter? If not, that may explain why your heat pump keeps turning on and off. It doesn’t take long for air filters to clog due to excessive debris, dust, and pet hair.
That’s why you must inspect your air filter once every 90 days to see if it must be replaced. Air filters can become clogged in as little as 3 months, especially if you have a dusty home. Your heat pump must work much harder once your heat pump becomes clogged.
This can strain the system and make your heat pump turn on and off repeatedly. Not only is this inconvenient, but it can also increase your energy bill. Keep several spare air filters on hand to ensure you can easily replace them every 90 days or as needed.
2. The Unit is Outdated
Like any part of your HVAC system, heat pumps sadly don’t last forever. That said, you can ensure your heat pump lasts at least 15 years if you keep up with maintenance. A well-maintained heat pump can last up to 25 years, but that’s uncommon.
Your heat pump’s performance will likely start to suffer once it approaches 15 years old. By then, it may turn on and off without finishing a full cycle. This happens because the parts become worn with time and cannot always complete a cycle.
It’s typically worth the cost to replace your heat pump after 15 years. That’s especially true if it needs expensive repairs. After all, why not put that money toward a new unit that will last 15-25 years?
3. Dirty Condenser or Evaporator Coil
Heat pumps have an evaporator coil and a condenser coil that are necessary for their operation. The condenser coil is located in the outdoor unit that’s connected to your heat pump. Naturally, this part can easily become dirty as it’s exposed to the elements, dirt, dust, and even fallen leaves.
The evaporator coil is also vulnerable to dust and debris as it’s right by the air handler inside your home. Your heat pump’s performance will suffer if either part becomes dirty or clogged. This can lead to high energy bills and poor performance.
Unfortunately, it can also cause your heat pump to turn on and off, seemingly at random. You can fix this problem if you clean the coil in most cases. However, you may need to replace either coil if they are beyond repair.
4. Your Heat Pump is Mismatched
The size and type of heat pump that you need is relative to the size of your home. You cannot count on a heat pump to work well if it’s too large or small for your home. For example, an oversized heat pump will draw too much power and may wear out quickly.
Similarly, an undersized heat pump cannot keep up with the demands of a large home. Whether it’s too big or too little, your heat pump’s performance will suffer if the size is incompatible. That’s why it’s worth the cost to hire a professional to install your heat pump.
This ensures that you can get an expert’s opinion and a heat pump that suits your home size. Otherwise, the unit may continually turn on and off.
5. Refrigerant Leak
Without refrigerant, your heat pump cannot transfer heat throughout the system and your home. Refrigerant leaks are common within many pieces of HVAC equipment. Short cycling is often caused by a refrigerant leak, and it’s frequently accompanied by hissing sounds.
Refrigerant lines are prone to wear and tear and loose connections that make them leak. Such leaks can make your heat pump short cycle, and they are also bad for the environment. A refrigerant leak can also cause your evaporator coil to freeze.
DIY refrigerant leak repairs can end in disaster as you may further damage the lines. Instead, it’s worth calling HVAC technicians to repair the leak.
6. Faulty Thermostat
Many common HVAC problems, such as a short cycling heat pump, are caused by a faulty thermostat. Your thermostat must communicate with your HVAC appliances to control them. Wiring issues, dead batteries, or an outdated thermostat can make this seemingly impossible.
It’s easy to jump to conclusions and assume your heat pump is to blame for the problems you’re experiencing. However, experienced HVAC technicians often inspect the thermostat to rule it out. Your thermostat may simply need to be rewired or replaced altogether.
How Many Times Should a Heat Pump Cycle On and Off?
A healthy heat pump may cycle on and off 2 to 3 times per hour. It depends on the temperature in your home and what you set your thermostat to. However, you should feel concerned if the downtime between cycles exceeds 10 minutes.
This may point to a refrigerant leak, dirty coils, or a clogged filter. Heat pumps typically run more often when they are over 10-15 years old.
We Can Fix Your Short Cycling Heat Pump
At Queen B Plumbing, we frequently install and repair heat pumps. Short cycles can make you feel like your heat pump is broken, but that may not be the case. Our team never jumps to conclusions and our thorough inspections yield quick results. Call Queen B Plumbing at (908)-633-1333 if your heat pump keeps turning on and off without explanation.
