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3 Signs That Your Central Air Conditioner is Low on Refrigerant

Refrigerant is a gas that is used in the heat exchange process in your air conditioning unit. It is an important gas, and if it starts to leak then you will notice that the performance of your air conditioning unit will start to degrade. It is important that you clean the air filters and keep tight seals on your air conditioning unit, and that you keep the refrigerant topped up to appropriate levels as well.

Here are three signs that your central air conditioner is low on refrigerant:

1 – Your Air Conditioning Unit is Blowing Hot Air

This is the common sign that your air conditioning unit is low on refrigerant. The job of the refrigerant is to cool the air as it passes through the unit. If there isn’t enough refrigerant in the system, then your unit will start to blow lukewarm, or even actually warm, air.

There are other problems that can cause the same fault, though, so warm air by itself is not a perfect warning sign. Your air conditioning unit might start to blow warm air if the grilles and vents are blocked, or if there is a fault with the compressor. Even more embarrassingly, it can also happen if your thermostat fan is set to ‘ON’ instead of being set to ‘AUTO’ so be sure to pull out the manual and check all of the settings before you call out a technician. A few seconds of checking the most obvious things could save you from needing to pay an expensive call out fee for something that turns out to be a non-issue!

2 – The Refrigerant Line Has Ice Appearing On It

If your refrigerant has been leaking, then the refrigerant line will be lower pressure than the surrounding area. The change in pressure can lower the temperature, and this could cause ice to appear. This can be quite a problem here, because the low pressure leads to low temperatures, which may eventually cause the evaporator coil to freeze. This exacerbates the problem by causing cold liquid refrigerant to pass through the refrigerant line. This will then cool the line, and if there is any moisture in the air around it, the liquid will condense onto the line and eventually freeze.

Just as with the issue of blowing hot air, ice on the refrigerant line isn’t a guaranteed sign of low refrigerant. A frozen evaporator coil or some other issues could cause the refrigerant line to become very cold as well. It is a good warning sign, though, and it’s worth checking your refrigerant pressure levels if you have access to the gauges to do so.

3 – You Hear Hissing and Bubbling Noises

The refrigerant, when the levels are correct, should be under a lot of pressure. So, when a leak first starts you will hear a hissing or bubbling noise. If it’s quite a serious leak, then you may hear a noise like someone squeezing a balloon that has a small hole in it.

Note that a leak is the only reason that refrigerant levels will drop. The refrigerant in your air conditioning unit does not get used up over time. Very small leaks can take a couple of years for the refrigerant levels to fall and may go unnoticed. Most leaks are not small, however, they are serious and cause drops at a faster rate.

Fixing the Leak

Be aware that according to the law, professional technicians are not allowed to top off air conditioning units with more refrigerant if they know that there is a leak. It is not good for the environment to risk releasing refrigerant into the atmosphere, and it would be ripping you off as a consumer. Refrigerant is expensive and the ‘top off’ will be temporary because the replacement refrigerant will escape as well. In addition, you could be running the risk of having the air conditioning not work properly and eventually become damaged if it is forced to run on insufficient refrigerant.

It makes far more sense to call a technician out to find and fix the area with the leak, and then add more refrigerant once the leak has been resolved.  If you are using an air conditioning unit that is currently relying on R-22, or Freon, as its refrigerant then you should get that changed as soon as possible. Freon/R-22 is bad for the environment and is being phased out under the Montreal Aggreement. Because of this, the price of R-22 has increased dramatically in the last few years and that is a trend that is only going to continue. It could save you a lot of money in the long run, and would also protect the environment, if you were to update your compressor to one that uses POE  oil, and then changed your refrigerant to one of the R-22 alternatives such as bluon tdx 20. Another option which you may want to consider if you have a serious leak is to completely replace your air conditioning unit with a more modern one. The latest units run quieter and are more energy efficient. They are also likely to have a lower long-term maintenance burden. Yes, you will have to pay a little extra up-front for them, but it will be worth it in the end to get something reliable and that is cost-effective to run.

Whether you decide to get a new unit or to just stick with the unit you have, it’s a good idea to have your air conditioning serviced on a regular basis. Get it serviced before the summer, so that if any issues are identified you will have time to fix them before the air conditioning is really needed. Preventative maintenance could save you a fortune in the long run and it will help you to avoid a scenario where a leak goes undiagnosed for a long time then turns out to be a serious problem. It makes sense to flag up potential issues before they do damage to any of the major parts of the unit.