Discovering ice on your heat pump’s outdoor unit during the summer can be alarming. Georgia is known for its hot summers. Even if your heat pump’s outdoor unit is in a shaded area, it won’t be exposed to subfreezing temperatures during the summer. But heat pumps can still freeze up during this otherwise hot and humid time of year.

Dirty Air Filter

A dirty air filter may cause your heat pump’s outdoor unit to freeze up. Like air conditioning systems, heat pumps require proper airflow to cool indoor spaces. Your heat pump will force air over an indoor unit to collect heat from your home’s interior. It will then release this heat by forcing air over an outdoor unit.

Your heat pump’s airflow will be restricted if it has a dirty air filter. Air must pass through a filter at the indoor unit. If the air filter is dirty, it may not absorb a sufficient amount of heat from your home’s interior. The temperature of the refrigerant will then drop, which can result in the outdoor unit freezing up.

Refrigerant Leak

One of the most common causes of a frozen outdoor unit during the summer is a refrigerant leak. Refrigerant runs between your heat pump’s indoor unit and its outdoor unit – all while collecting and releasing heat. If your heat pump has a leak, it will gradually lose its refrigerant.

As your heat pump’s refrigerant levels begin to drop, so will the pressure inside of it. This can lead to poor cooling, and it can lead to a frozen outdoor unit. Once your heat pump’s refrigerant has been completely depleted, the outdoor unit will no longer freeze up. Nonetheless, the early and middle stages of a refrigerant leak can lead to a frozen outdoor unit.

Dirty Evaporator Coil

A dirty evaporator coil may cause your heat pump’s outdoor unit to freeze up during the summer. The evaporator coil is part of your heat pump’s indoor unit. Heat pumps and air conditioning systems both have an evaporator coil. The evaporator coil will absorb heat so that it can be transferred to the outdoor unit.

If your heat pump has a dirty evaporator coil, it won’t be able to effectively cool your home. It will absorb less heat, and it will suffer from restricted airflow. You can replace a dirty air filter. If the evaporator coil is dirty, though, you should consider getting it professionally cleaned and inspected, instead.