Why is My Heat Pump Freezing Up in the Summer?

We all know what to expect in summer: hot days. What we don’t always know to look for is a heat pump that’s frozen in summer. For many of us, the very idea of a heat pump freezing up in summer during the hottest months of the year doesn’t make a lot of sense at first. 

Having your heat pump iced up in summer is actually a common problem for homeowners, so pay attention in case it happens to your unit. Getting the issue corrected quickly and learning how to prevent your heat pump freezing up in summer is important… unless you want to have to replace the entire unit or live without effective heating and cooling in your home.

If you’re hoping to learn what causes a heat pump to freeze up in summer, then read on to learn more about this piece of equipment and why it might end up iced over during the hottest months of the year.

What is a Heat Pump?

Before you can figure out the answer to your question, “Why is my heat pump freezing up in summer?” you have to learn what a heat pump is and a bit about how it works. 

A heat pump is a piece of equipment often installed outside your home that connects with your home’s HVAC system. Much like an air conditioner, a heat pump can provide cool air for your home, but it can also provide heat in the winter.

Heat pumps do not create heat or cool air. Rather, they redistribute air to create the right temperature indoors. During the hot months of the year, they absorb heat and warm air from inside your home and pull it outside to cool your home. During the cooler months, they pull heat from the cold outdoor air or even from the ground and transfer it inside. Heat pumps run on electricity and use refrigerants, a fan coil, and a compressor to transfer the appropriate temperature air.

So, what causes a heat pump to freeze up in summer? Let’s get to some possible reasons why you may have a heat pump outside unit frozen in summer.

What Causes a Heat Pump to Freeze up in Summer?

Refrigerant Levels Need Correction

If your heat pump is running low on refrigerant—or if someone without the right skills and knowledge over-filled your refrigerant—then your system won’t be able to operate correctly. Low refrigerant levels lead to a pressure drop, which can lead to the coils being much colder than what’s normal. This is perhaps the most common cause of a heat pump freezing over.

Dirty Coils Need Cleaning

One of the most common maintenance issues that can result in a heat pump frozen in summer is dirty coils. As your heat pump operates, dirt and other debris can build up inside the unit and on the coils, insulating it from any warm air blowing through. This grime layer causes your coils to become cold and starts the process of freezing. 

Restricted Airflow Needs Correction

If you find yourself with a heat pump iced up in summer, it could be due to poor airflow. If your heat pump is unable to transfer air like it’s designed to do—either unable to draw air or unable to push it—then it can cause the unit to freeze up. This can be due to dirty air filters, a faulty blower, or even blocked return vents. Any time there is a lack of warm air blowing across the coils, your heat pump is at risk of freezing over.

How to Prevent Your Heat Pump Freezing up in Summer

Scheduling regular preventative maintenance is the best thing you can do to prevent your heat pump freezing up in summer. Scheduling an appointment with an HVAC specialist to check, clean, and tune-up your unit every spring and fall (before the weather gets really hot, and before it gets really cold) can help keep your heat pump working as it should.

Things you can do as a homeowner to keep your heat pump working optimally is to change your air filters regularly. Dirty air filters can cause a lot more harm to your HVAC system than perhaps you are aware. Dust, hair, and dirt particles can get swept into your unit, coating the insides, and causing it to malfunction in a variety of ways—including freezing up.

It’s also important to avoid blocking any vents in your home since this can restrict airflow and keep your heat pump from working optimally. Don’t put furniture, clothes, decor, or even storage boxes and bins in the way of vents for any extended period of time.

Lastly, never attempt a DIY heat pump repair unless you have all the appropriate skills and knowledge. Something that may sound simple—like replenishing the refrigerant levels or tightening some loose bolts—can be a highly sensitive task. Your heat pump is a complicated piece of equipment, and for part of it to operate correctly, all of its moving pieces need to operate correctly. A “harmless DIY fix” could cause an unpredictable amount of damage.

Schedule Your Maintenance Visit Today

John C. Flood can repair a variety of heat pump issues, including a unit that is frozen over, so if you find yourself asking, “Why is my heat pump freezing up in summer?” you know who to call! Like we mentioned before, it’s important to react to a frozen unit quickly to prevent additional damages from occurring and to get your unit up and working as fast as possible. Call John C. Flood to schedule your maintenance visit or talk about setting up a preventative maintenance check.