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Should You Replace Your Evaporator Coil or the Whole AC Unit?

AC Unit on grass

There are plenty of things that can go wrong with the average air conditioner. Fans can fail, leaks can develop in refrigerant lines and other critical components can give out, necessitating a major repair to get the system working again. However, there arenandrsquo;t many problems bigger than a failed evaporator coil. When this happens, youandrsquo;ll have some big questions to answer - and theyandrsquo;re not easy for the average homeowner to make. Perhaps the most important of these questions is if you should make this big repair or invest that repair money in a full system replacement. This blog will take a closer look at this question and help you come up with the answer should you find yourself in this undesirable situation.

What Is the Evaporator Coil?

First things first. In order to decide whether to repair or replace, you need to understand whatandrsquo;s going on with your air conditioner. Your evaporator coil is located in the indoor half of your air conditioning system. This coil is essentially a long, winding metal tube (usually made of copper). This tube typically runs through a grid of cooling fins and looks somewhat like the radiator youandrsquo;ll find in your car.

Your evaporator coil absorbs heat and air that is pulled through your air conditioner is forced over this coil. Filling the tubes in your coil is a constant flow of extremely cold refrigerant. This refrigerant absorbs heat out of the air that passes over the metal coil and cooling fins, leaving the air cool, cold and dry. Once the warmed refrigerant passes out of the coil, it continues back through your air conditionerandrsquo;s cooling cycle where it is cooled again so the process can repeat.

What Can Go Wrong with Your Evaporator Coil?

Aside from the refrigerant within the metal tube, no part of this device actually moves. So what can actually cause your coil to break down? One of the most common problems is a dirty evaporator coil, caused by either inadequate air filtration or a dirty air filter. A dirty coil canandrsquo;t transfer heat as well as is needed and this can cause everything from inefficient and ineffective cooling to your air conditioner freezing over entirely. When your air conditioner freezes, your coil could sustain serious damage to the cooling fins or even damage to the pipe itself.

Evaporator coils can also sustain damage because of moisture. Because these coils get extremely cold, any water vapor that is in the air that passes over them often condenses back into liquid form. Eventually, enough of this vapor accumulates and forms droplets. Droplets eventually form into fairly large quantities of water and this water needs to be disposed in order to keep your air conditioner dry. This is why air conditioners all have a drain line that needs to be regularly cleaned and cleared.

Other issues can also damage your evaporator coil. For example, if your refrigerant lines develop a small leak, the pressure in your lines will drop. When the pressure drops, your evaporator coil can suffer for it. Likewise, if your refrigerant system is overfilled (something that happens far too often when people attempt to make this repair themselves), the amount of pressure in the line can cause damage to the coil itself, particularly if the line has become brittle with age or due to freezing cold temperatures.

Should I Repair or Replace?

There is no easy answer to this question. Everyoneandrsquo;s situation is different, and therefore what might be true for one person doesnandrsquo;t always hold true for another. Here are some general tips you can follow in order to make a smarter decision:

  • If your air conditioner is still under warranty, replace your coil. Major defects like a faulty coil are covered under warranty and therefore, you should take advantage of this protection. Odds are, the rest of your air conditioner is probably in great shape and can serve you for many years to come. Simply file a warranty claim with your manufacturer and let them fix the issue for you.
  • If your air conditioner is more than 20 years old, replace the whole system. Air conditioners generally last about 15 to 20 years before you should start to consider replacement. If you have taken good care of your system, you might get up to 25 years of use. If your system is more than 20 years old, however, itandrsquo;s usually a better idea to invest in a replacement instead of whatandrsquo;s likely going to be a major repair.
  • If our technician says your problem can reasonably be repaired, then youandrsquo;re probably safe to do so. Our technicians can tell you how serious your problem is and if they think a repair will be good enough to reliably keep your home cool, then youandrsquo;re in good hands. If not, you might want to consider a total replacement.
  • If your energy bills are already inexplicably high, replace your entire system. Cooling is a huge expense during the summer and if your bills have been way higher than usual so far, then itandrsquo;s probably a good idea to invest in a more energy-efficient replacement. Over time, that investment can help pay for itself.

If your air conditioner stops working due to your evaporator coil or any other major component, make the call to Valley Heating, Cooling, Electrical and Solar at (408) 868-5500 and schedule your service appointment today.