Homeowners rely on their heat pumps to keep them warm and comfortable in cold weather. Like all HVAC components, heat pumps can malfunction for many reasons. One common cause of heat pump failure is excessive ice buildup.  It is more common in winter months. You may notice that the vents only produce cold air, or that the heat pump runs when it is not supposed to. Worse yet, the unit may stop working altogether.


Excess ice is one of the leading causes of heat pump problems in cold weather. Although a little ice or frost is normal, the last thing a homeowner wants to see is a dense layer of ice over the entire outdoor unit. Ice build-up can damage the coils, fins, and the delicate fan blades, and may lead to compressor failure that permanently damages the unit beyond repair. A heat pump that is working properly will periodically enter a defrost mode, temporarily reversing the flow of refrigerant and allowing the ice to melt off. This process can be interrupted by any number of problems, many of which may be prevented by regular maintenance. Another way to avoid this altogether is to make sure you have a drain pan heater. This prevents the buildup of ice on the outdoor unit altogether.


How should you handle ice building up on your mini-split? A good first step is to make sure external factors are not causing the problem. Keep gutter water from draining onto the unit. Remove snow and leaves that may be blocking the coils and ensure that the unit is not sinking into the ground. Making sure when the unit is installed, they place it on raised concrete blocks. This will protect it from the soft ground and make it a little less vulnerable to the elements and allow proper draining.

If you get these issues under control and ice continues to build, it is time to consider more severe problems. These may include:

  • A problem with the reversing valve that prevents the refrigerant from warming the coils
  • A faulty thermostat or temperature sensor that fails to trigger the defrost mode
  • Low refrigerant or a possible refrigerant leak
  • Problems with the outdoor fan motor

Whatever the cause, it is essential to remove the ice buildup as quickly as possible. However, you should never use a hammer or a sharp object to break the ice. Mini-split components are far too delicate for that, and you will end up with even costlier damage.


Once you suspect a problem, call the professionals at The Heat Pump Store. Our technicians have expertise in ductless heat pumps and can guide you to the right solution. We will do our best to walk you through troubleshooting steps you can take with professional guidance over the phone. Our experts will walk you through the process and answer any questions you may have. If necessary, we will promptly schedule a skilled service technician to fix your system.

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In some cases, heat pump icing should only be handled by a professional technician. Unless you have significant training and experience with heat pump repair, attempting to fix the problem yourself could be dangerous and may cause further damage to the pump. The team at The Heat Pump Store can address these problems and perform preventative maintenance to keep your heat pump running smoothly. Service technicians can check the insulation levels, find refrigerant leaks, and test the voltage and pressure. They can also carefully clean the coils using environmentally-safe chemicals and compressed air and can make sure all motors and fans are working correctly. They might be able to solve the problem by repairing or replacing one component instead of replacing the entire unit. These steps will keep repair costs to a minimum and help keep your home at a comfortable temperature all winter.

Contact The Heat Pump Store online today or call 877-509-2961. We also have conveniently located showrooms in Eugene, Portland, and Salem.