Heat pumps are a handy and reliable appliance to have at home, especially when the cold weather sets in. Compared to traditional heating systems, it can help you save on energy expenses. If your heat pump system is designed for the entire home, you may not even need to back it up with a secondary heating source. Whether you live in a predominantly cool or warm climate, having one installed in your home is a worthwhile investment.
Like most HVAC systems, a heat pump can suffer issues that may prevent it from performing its intended function. One such example is a frozen heat pump. While it’s normal for frost to gather on the unit whenever it’s cold outside, there may be instances when it can indicate a bigger problem. Failure to address it can cause ice to accumulate further, damaging your heating system and causing it to stop working entirely.
Read on as Air Products & Services, one of the leading providers of heating and air conditioning replacement, provides an overview of frozen heat pumps and what you can do to prevent them from icing up in winter.
What Happens if Heat Pumps Ice up in the Winter?
To heat your home in the winter, heat pumps pull warm air from the outside. Even if outdoor conditions reach below-freezing temperatures, they can still heat your home efficiently. This is because heat pumps are partnered with a natural gas furnace option that the furnace can use when the temperature drops below a heat pump’s threshold. Since heat pumps use a smaller amount of electricity to operate, they are less expensive to run than gas furnaces.
If you notice ice accumulating in your heat pump, you might think something is wrong with your unit and may require a heating or AC troubleshooting system service. However, this is only a normal occurrence. As it does its job of heating your home, frost can form on the coils. As the unit generates heat, the refrigerant turns to gas and condenses when it meets the outdoor coil. In the winter, this condensation can freeze. To prevent this from happening, the unit will switch to defrost mode when the weather gets colder.
How Does a Heat Pump Defrost System Work?
When your heat pump reaches a certain temperature, the defrost cycle automatically switches on to keep your unit functioning smoothly. This defrost function is an important feature, especially for heat pumps used in cooler, harsher climates. This way, you keep your heat pump from icing over completely. To save energy, however, it doesn’t run constantly. Instead, it uses the defrost function only when necessary.
Your heat pump is equipped with temperature sensors that help trigger the defrost function. It also has a timer that requires the compressor to run for a given time before it will start the cycle. Depending on the manufacturer, the timer’s duration lasts from 30 minutes to 2 hours. Some manufacturers program the defrost system to start the time after the sensor has recognized the frost, while others start the timer after the last defrost cycle, ignoring the sensor until the unit has run for the selected time. Most defrost control limits the cycle to a maximum of 10 minutes. This is more than enough to keep your unit functioning all through the winter season.
When Are Frozen Heat Pumps Considered a Problem?
Temporary ice-ups are perfectly normal. However, if the heat pump freezes up for more than four hours or doesn’t seem to be defrosting properly, it’s probably time to bring in a heating or AC repair expert. Failure to address the latter can damage the unit and cause it to malfunction. When coils are blocked by ice completely, they will be unable to pull in cool air from the home, decreasing your system’s heat output capacity. Not only that, but a severely iced-up heat pump can also break the fan blades and cause refrigerant leaks.
In addition to a faulty defrost sensor, ice buildup can be caused by low refrigerant levels, dirty air filters, or a stuck reversing valve. Perhaps a component inside the heat pump unit malfunctioning, such as the thermostat, temperature sensor, or refrigerant metering device. Poor drainage, outdoor motor failure, or even improper leveling of the unit can also cause your heat pump to freeze.
Contact a professional heating or AC troubleshooting system expert as soon as you notice any of these signs:
- The heat pump unit is completely frozen over a long period.
- The top of the unit and inner coil is covered in ice.
- The defrost cycle is not activating as it should.
- Air is not being pulled into the fins of the unit.
What Can You Do to Prevent Iced-up Heat Pumps?
Fortunately, there are many ways you can prevent your heat pump from freezing. These include:
- Changing your air filters. Over time, your HVAC air filters can become dirty and clogged. Without proper maintenance, this can cause your heat pump to freeze in the winter. To ensure air is flowing through your heat pumps smoothly, change your air filters and keep them clean.
- Removing any blockages. Proper airflow is vital to keep the fans and coils running efficiently. In the winter, your heat pumps can be blocked by leaves, snowdrifts, and all kinds of debris. As such, you should clear them away. If the coils are dirty, take the time to clean them to prevent them from freezing.
- Scheduling regular maintenance. One of the best ways to prevent heat pumps from freezing during winter is to invest in regular maintenance. A heating and AC repair technician can inspect your units and look for issues that can lead to frozen heat pumps. By keeping up with your HVAC tune-ups, you keep your system running smoothly all year round.
For top-quality HVAC services, look no further than Air Products & Services. If your heat pump is experiencing issues, you can count on our experts to fix them and ensure your continued comfort at home. Our team of professionals is determined to assist you when it comes to your heating and air conditioning replacement, maintenance, and repair needs.