How Do I Inspect My Air Conditioner? | The Light Lab

How Do I Inspect My Air Conditioner?

Thinking about some Do-It-Yourself (DIY) home improvement projects for your Texas home, but you’re not really sure about what to do or where to start? You’ve come to the right place! Welcome to the DIY Energy Efficiency Tips series from First Choice Power. We’ll show you how to improve the energy efficiency of your home, including hints that make the jobs easier.

How Do I Inspect My Air Conditioner?

Late spring in Texas means more air conditioning. For most Lone Star homes, that’s a whole lot more expensive than winter heating bills. While your HVAC system may seem complicated, there are actually several things you can do to increase your HVAC’s energy efficiency and save money. Plus, it can help keep you and your family comfortable all the way through the long hot summer.

To begin, most folks already know there are two parts to a central air conditioning system: an exchanger and blower inside the home and a condensing unit and compressor outside. These machines are connected by two lengths of tubing that contain coolant. When the system is running, one line will be warm or hot while the other, covered in insulation, will be cold. Look for dirt, dust, and loose connections, and keep an ear cocked for wrong noises.

Before beginning, always turn off the system before you touch or clean any of its parts!

How Do I Inspect My Air Conditioner? | The Light Lab

Inspecting the Inside Half

The heat exchanger coil and blower handle circulate air inside your home. The biggest problem this air handling system faces is dirt and dust —it can clog filters, reducing circulation, collect on motors and belts, causing friction and wear, and it can choke off condensation drains, leading to water damage. Let’s go over these easy tasks you can perform to prevent all of that from happening.

Change the air filter. A clean furnace filter allows more air to flow through the system, where it is cooled more rapidly and blown with more force to better circulate through your home and improve its energy efficiency. Dirty furnace filters restrict the amount of air that is pulled into the air conditioning system’s fan. Consequently, less air can be cooled and dehumidified by the system —causing higher electricity usage and raising your electricity bill. Always use the manufacturer-recommend MERV-type.

Inspect the blower compartment. Look for large clumps of dust or dirt. Wipe or vacuum out the housing. If you’ve been hearing squeaks while the system is running, check the bolts or screws that hold the blower in place to see if any are loose. One at a time, carefully check for loose wire connections to the blower and make sure none of them can get caught up in the blower or any motor belt.

Inspect the evaporator coils for dirt.  This is also important if this is a heat pump system. Over time, dust and dirt can get trapped on the evaporator coil fins so that they may need to be cleaned. If you notice it happening frequently, it indicates that the air is not being filtered or there is a leak in the duct work that’s drawing in unfiltered air. The danger is that it could cause the system to freeze and ice-over

Clean the evaporator coils. Begin by turning off the system. Carefully remove the access panel and look for dust clogs on the A-frame shaped cooling coils. BE VERY CAREFUL not to bend or damage the coils or the any of the connections as this could cause coolant leak and a steep repair bill. Gently use a dust wand vacuum attachment to remove the dust. Wipe off any stubborn clogs of dust with a cloth and mild spray cleaner. For stubborn grime, you can get foaming AC Evaporator Coil cleaner. Lastly, replace the access panel.

Check the condensate drip pan and drainage connections. Hideous gunk made up of mold, dust, and other stuff can collect and grow in a damp condensate pan and block the drainage connect. First, make sure water is draining from the pan. Next, use a shop vacuum to suck out any debris that might have accumulated in the pipe. Many HVAC service techs install a small PVC clean-out addition that anyone can build for less than $2.00. Lastly, pour a little bleach or white vinegar down the drain pipe to inhibit mold growth and prevent future clogs.

If you continue to have problems with condensation failing to drain, then it’s probably time to bring in an air conditioning professional.

Test fire the system to be sure it cools properly. Set the thermostat to few degrees warmer than it is in your home and turn it to cool. Allow the system to run for a few minutes and then set the thermostat back down to your preferred setting to allow the system to shut down normally. If the system doesn’t operate properly, double check everything that you’ve done and make sure you haven’t accidentally dislodged or loosened a wire. If you still have a problem, bring in a professional.

How Do I Inspect My Air Conditioner? | The Light Lab

Looking Outside

The outside condenser works best if air can flow freely all around it. First, remove any leaves, brush, or vines from around it that might hinder air circulation.

Check for excessive rust on the sides.  Rust can be a sign that dogs may be “marking” it as their territory. Corrosion can damage the unit and cause coolant leaks. Replace any torn or missing pipe insulation. Insulation keeps the coolant cold when the system is running.

Look through the fan grate into the condenser for frayed or loose wires. Bad wiring can lead to dangerous electrical shorts and fires. Frayed wiring can be a sign of gnawing rodents or other pests that spent the winter nesting inside. If any branches or debris have fallen inside, you can remove the fan-grate to clear them out.

Make sure the fan can spin freely. With the system shut down, use a pencil or long screw driver to nudge one of the fan blades into motion. The blades should spin freely. If they don’t, something could be wrong with the motor. Get an assistant to turn the system on while you watch the fan. Turn the system off immediately if you notice something isn’t right.

Clean the condenser fins. The condenser circulates the coolant through coils of tubing that are attached to delicate metal fins. The condenser fan blows air around the coils to cool them but dirt and dust clogging the cooling fins reduces air circulation.Every so often throughout summer, wash out the cooling coils with a hose. Be sure to turn off the air conditioning before hand.

Extra Tips

A Lot of Shaking — If your unit is vibrating and shaking when it’s running, it’s because it’s not sitting evenly on the ground. You need to find some way to shim it in place and eliminate that vibration. Vibration and shaking can ultimately damage welds and cause expensive coolant leaks.

Winter Covering— AC condenser covers sound like a good idea but most professionals advise avoiding them as they make the unit a snug winter home for rodents that chew wiring and gnaw holes in insulation. Place a piece of plywood over the fan grating on top to prevent leaves, sticks, and other debris from falling inside during the winter.

Beware the Bulgy Capacitor — Your outside condenser unit will make some sound and vibration when it starts up. It’s a good idea to learn that noise because one of the first signs of a problem can be when it makes the wrong noises as it starts. If your home’s outside condenser is slow start or noisy it could be a sign that the power capacitor is going bad. Capacitors do a job similar to batteries in that they hold a charge and help smooth out small drop outs in electrical supply. A normal capacitor is cylindrical with flat ends. Capacitors (or “caps”) wear with age and if they begin developing bulges at either end or start leaking it’s a sure sign they won’t last much longer. To check whether your condenser has a bulge, turn off the power supply or circuit break to the condenser then find and remove the access panel. Look for the biggest cap you can find and see if it’s bulgy or leaking. DO NOT TOUCH THE WIRE CONNECTIONS OR CONTACTS! This capacitor uses high voltage! Caps can hold a dangerous charge (enough to badly burn or even kill you). If your condenser has a bulging capacitor, it’s best to contact a qualified and licensed repair technician to come and replace it.

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Vernon Trollinger is a writer with a background in home improvement, electronics, fiction writing, and archaeology. He now writes about green energy technology, home energy efficiency, the natural gas industry, and the electrical grid.