AC Evaporator Coil Importance and Possible Issues

The cooling process that takes place within your home or building’s air conditioner involves a few different components, and one of the single most important here is known as the evaporator coil. When this coil is in good shape, the system will be able to properly spread cool air throughout a given space; if it’s not, efficiency will drop quickly while costs rise — and that’s if the system even operates properly at all.

At My Buddy the Plumber, we’re happy to provide a wide range of air conditioning maintenance, repairs and even new installations for clients throughout Utah. We regularly assist clients with evaporator coil-related issues and remedies, ensuring their system stays in great shape. What is the evaporator coil, why is it important, and what are a few of the common issues that sometimes arise with it? Here’s a primer, plus how our team of HVAC technicians will assist you if you’re having any evaporator coil issues.

Evaporator Coil Role and Importance

For those who are just learning about air conditioners, the evaporator coil is one of two coils that are integral to how the system works. The other coil is known as the condenser coil, and these work in tandem to create cooled air that can then be circulated throughout a space.

Warm air is pulled into the system and over the evaporator coil; as this happens, refrigerant within the coil absorbs the heat and becomes a gas. The now-warm refrigerant is then sent to the condenser coil, where it releases its heat and changes back into a liquid form. This cooled liquid is then circulated back to the evaporator coil so that the entire process can start over again, creating an endless cycle of cooled air for your home.

The evaporator coil, then, is constantly absorbing heat from the air being pulled into your system. Because of this, it’s prone to corrosion and other issues — but more on that in a moment.

First, it’s worth noting that the evaporator coil works best when paired with an AC unit with a compatible tonnage. In short, this means that a one-ton air conditioner will have an evaporator coil that can absorb about 12,000 British Thermal Units (BTUs) of heat per hour. A three-ton unit will have a coil that can handle about 36,000 BTUs per hour, and so on.

If you’re not sure what size your system is, you can check the model number; it will likely include a “1” for one ton, “2” for two tons, and so on. You can also ask your HVAC contractor during your next tune-up.

Common Evaporator Coil Issues

There are a few different issues that can crop up with an evaporator coil, and they often manifest themselves in similar ways. For example, you might notice that your system isn’t cooling as effectively as it used to, or that it’s taking longer to cool a space than normal. These are both signs that something is wrong with the coil itself, and there are a few possibilities for what’s actually happening:

• Dirty coil: Perhaps the most common problem, a dirty coil can cause all sorts of issues. As the name implies, dirt and debris will collect on the coil over time; this provides insulation that prevents heat from being properly absorbed. In some cases, the coil might be so covered that air can’t even flow through it efficiently.
• Refrigerant leaks: These are somewhat common in evaporator coils, and they can cause a host of issues. A refrigerant leak will cause the coil to freeze over, which then prevents it from absorbing heat as intended. This can quickly lead to an AC unit that doesn’t work at all, so it’s important to have any leaks repaired as soon as possible.
• Corrosion: Corrosion is another problem that’s relatively common in evaporator coils. This often happens when the coil itself is old, or when it wasn’t installed properly to begin with. In some cases, though, corrosion can be caused by a refrigerant leak; this is because the chemicals within refrigerant can eat away at metal if they’re not contained properly.

Signs Indicating Evaporator Coil Issues

Luckily, you’ll usually get some telltale signs from your HVAC system if your evaporator coil is having problems. These include:

• Warm air from vents: If the air coming out of your vents feels warm, that’s a sign that something is wrong with your evaporator coil. In most cases, this means that the coil itself is frozen over and can’t absorb heat properly.
• Rising energy bills: A dirty or damaged evaporator coil will cause your AC unit to work harder than normal; this, in turn, will lead to higher energy bills. So, if you notice that your bills have been rising for no apparent reason, it might be time to have your system checked out.
• Hissing or bubbling noises: These sounds usually indicate that there’s a refrigerant leak somewhere in your system. If you hear these noises, it’s important to shut off your AC unit and call a professional as soon as possible.

If any of these issues are present, and you’re able to confirm an evaporator coil concern through our team, the biggest question becomes whether to repair or replace the coil. This decision usually comes down to a few different factors, including the age of your system, the severity of the damage, and the cost of repairs. In most cases, it’s more cost-effective to simply replace an old or damaged coil; however, you might be able to get a few more years out of a good coil if it only has minor issues.

For more on this, or to learn about any of our air conditioning repair or replacement services, speak to the team at My Buddy the Plumber today.