Did you know that it’s normal for your heat pump to form a light layer of frost when working overtime? A completely frozen unit, however, is a different problem.
If you’re dealing with a frozen heat pump and it refuses to defrost for more than four hours, our experts at Service Emperor are here to help.
Below, we’ll explain how heat pumps work, common issues that cause excessive ice buildup, and the next steps you can take to restore your property’s comfort.
How Do Heat Pumps Work?
While heat pumps can’t directly produce hot or cold air, they can transfer heat from one area to another. For example, when you turn on your unit’s heating mode, it will absorb heat from outside to bring indoors and remove cold air from your property. In cooling mode, it does the opposite by moving the heat from indoors to the outside.
Heat pumps can offer this convenient dual functionality thanks to their refrigerant-filled evaporator coils. However, when heating mode is active, your heat pump’s evaporator coil might be colder than its surroundings. The temperature difference creates excessive condensation, leading to your heat pump freezing if the outdoor air is cold enough.
Luckily, all heat pumps come with a built-in “defrost feature” that melts the frost that accumulates on the unit.
A Breakdown of the Heat Pump Defrost Cycle
Heat pumps can reverse their operation and go into cooling mode to defrost. The refrigerant lines will absorb the warm air in your property and use the heat to melt the ice on the outdoor coils. This defrost cycle works in just a few minutes, and the unit returns to its regular function afterward.
If your heat pump stays frozen for over four hours, then you might be dealing with a hidden problem.
Top Reasons Why Your Heat Pump Freezes
Many issues cause excessive ice formation on your HVAC system, from faulty temperature sensors to clogged air filters. Let’s go over the most common ones below.
Malfunctioning Defrost Function
A bad defrost control board can stem from different component issues, including:
Poor Air Circulation
When your outdoor unit’s fan malfunctions, it won’t be able to pull air over the cold coils. With your heat pump not absorbing as much heat, the coils will further drop in temperature and create ice.
Some problems that can affect the performance of your blower’s fan blades include:
- Too much dirt or debris on the fan blades
- A faulty capacitor or blower motor
- A clogged air filter
Low Refrigerant Levels
Insufficient refrigerant levels produce excess pressure, and high-pressure refrigerant leads to poor heat circulation and colder coils. If you notice any leakage from your outdoor unit, don’t wait for it to become a frozen heat pump. Call our technicians immediately for fast and effective HVAC services.
DIY Solutions for a Frozen Heat Pump
When your heat pump freezes, don’t panic just yet. Let your unit’s defrost function kick in and wait for a few hours. If the problem doesn’t resolve itself, you can follow the helpful tips below to restore your property’s heating and air conditioning.
Cleaning Its Components
If the thin layer of light frost on your heat pump continues to accumulate, check if your air filter is in good condition. Replace it immediately if you find excessive clogging. Next, assess the condensing fan’s fins and clear away any debris that might be hindering its normal function.
How is your current weather? If it’s on the warmer side, you can try to wash off the ice accumulation using a garden hose. Never use a sharp object to chip away at the buildup because you might risk damaging your heat pump in the process.
Regular maintenance is always a good practice because it helps your unit save energy, extend its lifespan, and make its performance more reliable.
Activating the Defrost Function
When there’s an issue with your unit’s defrost function, you can try to turn it on manually instead. Keep in mind that not all air conditioning systems have this feature, so check your owner’s manual and see if your specific model has manual defrosting.
This fix is also just a short-term solution. If you want the defrost cycle to automatically turn on when the outdoor coil system begins to freeze, you need to call a professional technician.
Turning on the Outdoor Fan
Another temporary band-aid fix for frozen heat pumps is to turn on your fan manually. With the heating and air conditioning mode inactive, the untreated air passing through your outdoor coil system might be enough to thaw it out. Just like the manual defrost function, not all heat pump models come with manual fan settings.
Relocating the Entire Coil Sensor
The last DIY fix you can try is to change the position of your heat pump’s temperature sensor. When the sensor is in a warmer area than the rest of your outdoor unit, it might not start the defrost cycle when needed. Before attempting this option, mark your sensor’s original position so you can easily return it if it doesn’t work.
As a general disclaimer, all of these DIY treatments always carry a potential risk. Leaving the root of the problem untreated for an extended period can create serious damage. When in doubt, it’s best to leave the work to experienced HVAC professionals.
Did Your Heat Pump Freeze? Our HVAC Professionals Have the Solution
Did your heat pump unit freeze up at the most inopportune moment? If you’re looking for a permanent solution to your faulty heat pump model, let our HVAC tech team at Service Emperor do the heavy lifting.
By choosing the best company to assess your cooling and heating system, you can enjoy: