Refrigerant is often referred to as coolant or freon and these terms should be considered to be interchangeable for our purposes. This liquid can be considered as the blood in the circulatory system that connects the various AC components together. Refrigerant is kept under pressure by the compressor and circulated to absorb heat and move it outdoors. This process makes the indoor spaces feel cooler, but a lack of refrigerant will lower the energy efficiency, and eventually, the system may not function at all. In this article, we will look at four signs that your AC system needs a fresh refrigerant charge.

What is a Refrigerant Charge?

When the volume of the refrigerant drops, it causes a lack of efficiency and the heat isn’t removed. This makes it difficult to reach the desired temperature that you’ve set on the thermostat. Because the refrigerant is kept under pressure, there needs to be sufficient volumes to make the entire AC system work.

A lack of refrigerant can be caused by leaks in the lines that must be detected and repaired before a fresh charge. When the refrigerant is charged it’s topped up with new refrigerant to get the system working as intended. But, it’s important to understand that there are different types of refrigerants.

It may be tempting to simply refill the refrigerant yourself, but this is easy to get wrong. If you mix different refrigerant types it can reduce the efficiency of the entire AC system. For these reasons, we recommend that you contact your local heating and cooling specialist if your AC system needs a refrigerant charge.

4 Signs That Your AC System Needs Refrigerant

Let’s take a look at four common signs that may indicate that your AC system needs refrigerant. They are:

1.   Rising Energy Bills

If you keep a close eye on your monthly energy bills and they are consistently rising this could mean that your air conditioning system needs refrigerant. This is especially true if you have not made any significant changes in your home, such as new appliances, long-term visitors that consume more energy, and major temperature alterations.

The air conditioning system blows warmer air over the evaporator coil which is filled with refrigerant that’s kept under pressure by the compressor. The refrigerant absorbs this heat and then carries it outdoors where it’s released. If there is insufficient refrigerant in the system this will degrade the ability to remove heat during the cooling cycle. To compensate, the AC system will have longer running times, because it will continue to attempt to reach the temperature set on the thermostat. These longer running times for no boost in performance will drive up your energy bills.

For clarity, it’s important to state that there are other AC related problems that can increase your energy bills too. If you have an AC system that’s 10+ years old it will have degraded energy efficiency issues. If the system is poorly matched to the home there will be energy consumption problems. A system that is too small will run constantly because it lacks the power to cool the internal spaces. A system that’s too large will cool the spaces too quickly which causes short cycling issues. During short cycling, the system will turn on and off again quickly which consumes a lot of energy and stress on the components. Finally, a dirty air filter can restrict the airflow to the system which forces the air conditioning to run for longer which increases the energy consumption.

2.   Warm Air at the Supply Vents

When the refrigerant levels are lowered, the ability of the refrigerant to absorb sufficient heat per cooling cycle is compromised. For many people the first thing that they will notice is a lack of cooler air at the supply vents, If the refrigerant levels are very low this air may even feel warm and cooling is simply impossible.

Again, there may be other causes to investigate and a common cause of warm air at the supply vents is a dirty air filter. When the AC filter is clogged it’s difficult for the system to pull in sufficient volumes of warm air. This means that the AC system will have less cool air to distribute throughout the home and the air will feel warmer. Replace the air filter, if you can still feel warm air at the supply vents it’s time to call your local HVAC specialist.

3.   Ice/Frost on the AC System Components

There should be no ice or frost anywhere on your AC system components and this could be a sign that the refrigerant levels are low. The refrigerant temperature can drop below the level required to remove heat and this can cause a build up of ice on the refrigerant lines. If you take a look at the evaporator coil and it’s covered in ice this is a serious problem and it can damage the component.

There are other possible causes of ice and/or frost buildup. If the air filter is clogged the reduction in airflow can cause freezing in the evaporator coil. If the vents are closed in one or more rooms in the home, this can create freezing issues. Keep the supply vents open and free from obstructions, such as drapes and tall furniture.

4.   A Bubbling or Hissing Noise

If you can hear a bubbling or hissing noise emanating from the outdoor air conditioning unit there is a good chance that you’re hearing refrigerant leaking. The bubbling sound may be refrigerant leaking in a liquid state and the hissing is when it’s escaping as a gas. Unlike the other possible signs of a refrigerant leak, there are no other causes for these types of sounds. So, if you hear bubbling or hissing it’s highly likely that there is a leak somewhere in the refrigerant lines. This must be repaired before the system can be charged with refrigerant or the problem will continue.

If your AC system requires a refrigerant line repair or a fresh charge, contact your local heating and cooling specialist today.