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How to Tell If Your Heat Pump Is Low on Refrigerant?

Your heat pump uses refrigerant as a heat transfer medium. It needs enough of it at all times to function properly. But sometimes, your refrigerant might leak out of your heat pump, causing its levels to go too low.

You might have a refrigerant leak in your heat pump if you hear hissing and gurgling sounds coming from your heat pump. Other signs of the problem include a frozen evaporator coil and short cycling.

But that’s not all there is to know about heat pumps and refrigerant leaks. Keep reading to get a complete overview of how to spot this problem in your system.

Top signs of low refrigerant in a heat pump

Hissing sounds

Your heat pump relies on pressure to move refrigerant from one part of the system to another. When there’s a leak, this pressure can create a hissing noise. So if you hear hissing, that’s a good sign that you have a refrigerant issue.

Gurgling noises

Gurgling noises are another telltale sign of a heat pump with a low refrigerant charge. This noise tends to come when there are air bubbles trapped in the refrigerant line.

Frozen evaporator coil

You can also look at your evaporator coil for clues as to whether you have a refrigerant problem or not. This part is designed to absorb heat, but it won’t be able to do that with the right amount of refrigerant.

When your evaporator coil can’t absorb heat properly, it can freeze. That could happen because your heat pump has a weakened solder joint, a failed valve, or unsecured fittings.

Water leaks from your heat pump

You also want to keep an eye out for water leaks coming from your heat pump. This is the result of frozen ice on your evaporator coils dethawing. And when that happens, it’s generally a pretty clear sign that your heat pump has a refrigerant leak.

Indoor areas won’t get warm enough

Another big sign of a problem with your heat pump is not being able to keep your indoor areas warm enough.

There are lots of different things that can cause this to happen. But one is that you may have an issue with your heat pump refrigerant leaking.

When this happens, your heat pump may attempt to make up for the lack of warmth by using auxiliary heat more often. This is only supposed to come on when outdoor temperatures dip below freezing.

If your auxiliary heat comes on every time you turn on your system, that’s a sign of a problem. The same is true if the auxiliary heat runs for longer than 30 minutes.

Both of these issues could be symptomatic of a refrigerant leak in your heat pump.

Longer cooling times

When your heat pump is leaking refrigerant, it has to run longer to achieve the same temperatures. That means it takes the heat pump longer to cool your home. The air coming out of your vents should be as cold as you set the temperature on your thermostat. If the air isn’t as cold as it should be, then that can be another sign that you’re dealing with a refrigerant leak.

More humidity

Properly functioning heat pumps only take about 10 minutes to clear your home of excess humidity. If that’s not happening, then it could indicate that your heat pump isn’t working properly.

Short cycling

If your heat pump cycles more often than the average, this could be a sign. Your HVAC system relies on a closed-loop of refrigerant that heats and cools the air on a cycle. When there’s a refrigerant leak, that loop doesn’t function properly. It doesn’t have enough pressure to cool or warm the air effectively.

When this happens, the HVAC unit has to work harder with less refrigerant than it usually does. This can cause your heat pump to short cycle.

Higher than normal electric bills

Refrigerant leaks cause your heat pump to work harder than it normally does. This increases your energy bill since your HVAC unit isn’t operating as efficiently. So if you notice that your electricity bills are higher for no reason, it could be a refrigerant leak.

What causes refrigerant leaks in a heat pump?

When you have a refrigerant leak, it’s because there’s a small puncture hole in your cooling line. This can be caused by:

  • Wrong installation process and factory defects
  • Natural deterioration
  • Corrosion of copper tube walls
  • Weakening connections and vibration

How to prevent leaks

There are a few steps you can take to significantly reduce your risk of having a refrigerant leak in the future.

One of the best strategies is to have your system inspected and serviced every year.

Another idea is to enclose the outside part of your HVAC system with a fence. That will protect your unit from animals.

Another good strategy is to invest in a system with aluminum coils instead of copper ones. Formaldehyde is a chemical that reacts with copper. This chemical is present in your HVAC system. Copper corrodes a lot faster as compared to aluminum. And corrosion can do significant damage to your system. So it’s best to go with aluminum if you have the choice.

Understanding refrigerant

As you try figuring out whether your heat pump needs a new refrigerant or not, it’s worth taking a moment to better understand it.

Refrigerant is a heat transfer medium. It consists of a blend of chemicals that help it shift between being a liquid and a gas. This feature helps the refrigerant absorb heat by evaporating and releasing it via condensing.

But what you really need to know is that refrigerant allows your HVAC system to transfer heat from inside your house to outside of it and vice versa.

It’s not an energy source. Instead, refrigerant moves energy. That’s why you shouldn’t ever need to add more to your system unless you have a leak.

Is a heat pump refrigerant leak an emergency?

Refrigerant leaking out of your heat pump is something that you should deal with as soon as you notice it. That’s because when this occurs, it can lead to a variety of problems with your HVAC system.

For example, low refrigerant levels reduce the efficiency of your heat pump. They can also cause the heat pump to freeze over and the compressor to overheat. Problems like these could cause lasting damage to your system.

How often does a heat pump need a new refrigerant?

HVAC systems are designed with a closed-loop refrigerant system. So you shouldn’t need to replace it ever.

The only scenario in which you may need to add more refrigerant is if your system has a leak. Just keep in mind, you need to repair the leak before adding more. Otherwise, you’re just going to keep having the same problem over and over again.

Michael Joseph