5 Common Heat Pump Problems

Heat pumps are becoming more common, especially if you live in an area with milder weather. Just like an air conditioner or a furnace, problems with your heat pump can arise. 

To help you with potential heat pump problems, we’ve described the most common heat pump issues. You will also find some of the most common solutions to these issues.

That knowledge will help you know how to fix your heat pump and when you need to call a specialist. 

Heat Pump Not Turning On

One of the most common issues is your heat pump not turning on. The cause can be something quite simple. In some cases, your heat pump is simply not on.

In others, the situation can be more serious. Here are a few reasons that your heat pump is failing to turn on:

  • Power Source
  • Thermostat
  • Fuses
  • Starter Capacitor
  • Reversing Valve

Let’s take a more in-depth look into these issues, as well as some of the main ways you can resolve them.

Power Source

Most of the time, if your heat pump isn’t turning on, it is because there is no power. In this case, it is probably the circuit breaker.

Check your master breaker box and see if any switches have been kicked into the off position. All you need to do is turn it back on, and you are good to go.

If your breaker always kicks off, you may have electrical problems and will need to look into that. If you own a modular home or an older home, you may need to update your breaker box. 


First, see if your thermostat’s programming is set up correctly.

Sometimes, the thermostat may be set to turn your heat pump on at specific times rather than when your house reaches a certain temperature. Your heat pump may be in “sleep mode.”

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Always make sure your heat pump is turned on. Sometimes when power outages occur, the thermostat may return to its basic settings.

This is a quick fix, and you will just have to make a note for next time or change your thermostat settings.

Heating Thermostat

Sometimes, the thermostat can be miscalibrated. This means that the thermostat is unable to communicate with the heat pump.

If this is the case, you will have to get a professional to fix this issue.


Fuses are in place to protect your electrical system from a power surge. You may not be aware that a power surge has happened.

Check the electrical panel outside by your unit. You can replace those fuses for cheap and on your own.

Make sure to use gloves when replacing this part. The oil from your fingers can make your fuses go bad quicker.

Starter Capacitor

Just like your vehicle, you have a starter in your heat pump. It makes sure to “start” your unit.

To tell if your starter capacitor is broken, listen for a click sound. If your heat pump is making a small click as if it wants to turn on but doesn’t, this means your starter is bad.

There is not a simple way of fixing this. You will need to call a professional, who will then replace your starter capacitor with a new one.

Reversing Valve

This little part of your heat pump is why you can provide cold air in the summer and hot air in the winter with the same device.

If you can get cold air during the summer and everything works perfectly, but for some reason, the heat is not working, this may be the cause. Your reverse valve isn’t “reversing.”

This problem will need to be fixed by an expert.

Heat Pump Running Constantly

Sometimes your heat pump ends up running constantly. This is a big issue because if it runs constantly, then there is something wrong with your system.

It could be any of these:

Any of these are fixable, but if your heat pump constantly runs for long periods, it can break your unit entirely, which costs a pretty penny.


Whenever you have a problem with your unit, check the thermostat first. The temperature may be set too low or too high.

This mishap can be fixed immediately and will save you money.

If your thermostat is miscalibrated, then you will have to call a specialist.

Compressor Contractor

The compressor contractor provides the power to your heat pump, and if it is broken, it can cause your unit to run longer than usual. Your unit has to run for longer periods to keep your home at the desired temperature.

This will need to be replaced by a professional.

Air Filter

If your heat pump is continuously running, but your house is not heating or cooling. The problem may be airflow.

All systems have air filters that make sure dirt and outside particles do not get in and block the flow. Air filters aren’t meant to last forever.

Man Replacing Air Filter

When your air filter is full of dirt and dust, the air cannot make it into the home quickly.

This is an easy fix, and you should do this regularly (about every six months or less).  Figure out what the size of your filter is and change it out.

Some filters are reusable and can be cleaned for further use.


The best places to use heat pumps are areas with milder weather conditions. A heat pump’s purpose is not meant for extreme weather conditions, especially below freezing weather.

But nature can be unpredictable. If the weather where you live is uncannily cold for the winter, this may be why your heat pump is working overtime.

Heat Pump Blowing Cold Air In The Winter

The worst thing to happen in the dead of winter is to have your heat pump blow cold air. This issue can be easily fixed but not always.

Here are some causes of this issue:

  • Defrosting
  • The Fan
  • Refrigerant


In colder weather, sometimes things ice up. This includes your heat pump. Now your heat pump should be defrosting itself by temporarily turning on the air conditioner to melt the ice, but this does not always happen.

You may need to help it out by breaking off some of the ice. Be careful, though.

When there is cold weather, make sure water does not drip on the unit.

If water falls on the unit and the temperatures get below freezing, then this can freeze on your unit. The ice can make your unit work harder and wear out your system.


Your fan pushes the air throughout the ducts and into your home. If your fan is broken, this can cause cold air to circulate in your home during the winter.

You will need to call a specialist for this problem.


You need a refrigerant to cool and heat your home. When your refrigerant is low, your system can’t do either.

This can happen over time, but it can also suggest you have a leak somewhere. You will need a professional to recharge your system, and they can check for any leaks.

Heat Pump Blowing Hot Air In The Summer

It is never a good sign when your unit blows hot air in the summer. If this happens to you, here are the causes and what you will need to do:

  • Coils
  • Fan
  • Refrigerant


Coils help your heat pump create the cold air that circulates your home. When your coils get dirty, your unit is unable to do its job properly.

You can easily clean the coils yourself, or you can hire a professional to service your unit. Try to clean your coils once a year to prevent this problem.


When your fan is broken, it can’t circulate air. If there isn’t much air blowing from your vents, this can be the problem.

You will not be able to fix this on your own and need to get someone to look at your unit.



Low refrigerant can cause your unit to blow hot air. The refrigerant cools down the air going into your home.

A simple way to know if this is the problem: put a thermometer by one of the vents.  If the air is warm or higher than what your thermostat is set at, this probably is the cause.

An expert can tell you if your unit is low and recharge it for you.

Heat Pump Making A Noise

Your heat pump will make some noise as any unit will, but there are a few noises to look out for:

  • Metal sounds
  • Rattling
  • Ding or Ping/Pong sounds

Metal Sounds

Metal sounds can be expected within a system, especially since most parts are metal, but there can be issues that cause it. If your system seems like it is okay, then it isn’t anything to worry about.

If the sound is unbearable, you can contact a professional to help reduce the sound by adding insulation.

If your system isn’t running correctly and you hear these sounds, you may need to get someone to investigate the problem.


If you hear rattling, the cover panels may not be screwed on tightly. You will need to tighten the screws, and the sound should go away.

If you hear rattling in the ducts, you may have a loose part in there. That will need further investigation.

You don’t want those loose parts causing further damage.

Man checking HVAC ducts

Ding or Ping/Pong Sound

When hot air goes through the ducts, it expands while cold air shrinks. Sometimes this causes the ducts to expand, which creates this sound.

If your system is not running correctly, then you may need to call in a professional and explain what you heard. They will need to investigate to see if the sound is the cause or not.


Heat pumps are a great option for many homes. But like any system, heat pumps can develop problems.

As an owner of a heat pump, you need to recognize these problems. Then you will have the best chance of finding the right solution. 


The Most Common Heat Pump Problems

Heat Pump Troubleshooting