There are many aspects of air conditioner maintenance that are best left to professional HVAC technicians. This is understandable because it’s easy to make a mistake and botch a DIY repair which will drive up the final costs. But, there are some essential tasks, such as regular air filter changes, thermostat sensor cleaning, and outdoor coil cleaning that anyone can do. Most people have a basic understanding of their AC system and the connection between the indoor and outdoor units. There are many parts of the systems that are hidden out of sight but the outdoor coil is easy to locate. In this article, we will take a closer look at this key component and show you how to clean it properly.
What Does the Outdoor Coil Do?
Many people believe that an AC system cools their home, but this is technically incorrect, and understanding the true purpose is important. In reality, the air conditioning system removes the heat from the home and this makes the indoor spaces feel cooler. This may seem like a trivial distinction, but this key detail needs to be understood to explain the purpose of the outdoor coil. This component is also known as the condenser coil and it’s the outdoor part of a split-system AC unit or a heat pump. This system uses a compressor to convert liquid refrigerating from a gas to a liquid to transfer heat outdoors. The refrigerant moves in a cyclical manner to absorb heat and transport it from indoors to outdoors at the condenser coil. Without this key component, the AC system will not work efficiently and in some cases, it may not work at all.
How Do Outdoor Coils Get Dirty?
Because an outdoor coil is located outdoors it is exposed to the elements and the debris that can be typically found in a yard or out on the street. When it’s time to turn the AC on for the first time, it’s not unusual to find dead leaves, debris, moisture, and other contaminants in the outdoor unit. When the outdoor coil is dirty there may be degraded performance and energy efficiency. Virtually every professional HVAC company will clean the outdoor coil as part of a regularly scheduled maintenance visit. This will usually take place before the start of the cooling season to ensure that the system is ready for the warmer months ahead. Most of the time a company will do an excellent job, but some may simply spray the unit with a hose and this is not the right way to clean it.
What are the Consequences of a Dirty Coil?
Because the evaporator coil is connected to the refrigerant line with copper tubing it can have a dramatic effect on performance. This tubing connects the indoor and outdoor units to transfer the collected heat outdoors using the refrigerant. The coil must be clean and clear to dissipate this heat efficiently. The accumulation of dirt, grime, pollen, and other contaminants on the surface of the condenser coil will prevent the efficient removal of heat. There are three main consequences:
1. Frequent Repair Bills
When the AC system cannot remove the air efficiently, it will work harder in an attempt to reach the temperature set on the thermostat. It is a truism that overworked systems are always more prone to failure and HVAC systems are no exception. Over time, you may notice that the components fail frequently and in extreme cases, the lifespan of the system may be shorter than expected.
2. A Lack of Indoor Comfort
If the AC system cannot make the indoor temperatures cooler, you could be less comfortable when the hotter weather arrives.
3. Increased Energy Costs
Because the AC system is running harder to meet the thermostat setting, it will consume more energy. This will drive up the energy bills for no reason and the SEER rating will not be met.
How to Clean the Outdoor Coil Properly
There are seven steps to follow carefully to clean the outdoor coil properly and restore the lost performance and energy efficiency. They are:
Step 1: Turn Off the Power
To promote safety and protect the unit from further damage it’s important to turn off the power before the cleaning can begin. There may be a need to remove or move some components to properly clean the outdoor coil and this is why it’s essential to power the unit down.
Step 2: Check the Refrigerant Pressure
It’s not unusual to have refrigerant pressure that’s higher than required for the type and size of air conditioner installed in your home. So, it’s a good idea to check the refrigerant pressure before cleaning commences.
Step 3: Remove the Casing
The outdoor unit is protected by an outer casing, which must be removed to gain access to the condenser coil for proper cleaning. A disreputable HVAC company will simply hose down the unit without removing the casing which has limited effectiveness. Remove the screws, keep them in a safe place, and carefully pull the panels to gain access to the inside of the unit.
Step 4: Rinse the Coil
Use a hose to rinse the coil with clean water to remove some of the accumulated dirt and grime that can prevent thorough cleaning.
Step 5: Apply the Cleaning Chemicals
There are specific products designed for coil cleaning that are sprayed directly onto the coils. Follow the instructions carefully and when you’re ready, perform a final rinse to make the coil clean.
Step 6: Clean the Debris
Before you reassemble the outdoor unit, clean away the accumulated debris, such as dead leaves, straws, sticks, and more. This will make your cleaning efforts last for longer before you need to clean the coil again.
Step 7: Recheck the Refrigerant Pressure
If the cleaning was effective, the refrigerant pressure may have dropped to a pressure that’s more in line with the tolerances of the system. This is a sure sign that your cleaning efforts have been effective and you should notice that the system is more efficient.
Coil cleaning is pretty straightforward, but if you’re still unsure, contact your local HVAC specialist and they can clean the coil as part of some essential maintenance.