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How to make sure your air conditioner is working right

The Secret Guide for Super Moms #2 Checking Your Air Conditioner John C. Flood

"How to make sure your air conditioner is working right" is the second post in our four-part series, "The Secret Guide for Super Moms” — tips, tricks and hacks for busy moms who need to know everything that’s happening in their house.

When you live in or around Washington, D.C., you know that air conditioning is a must in the hot, humid months. And if you’re new to the area, you’ll soon find out – whether you live in D.C., Maryland or Northern Virginia – that once the heat cranks up, you and your family will need someplace cool to escape the muggy weather.


At the same time, you need to keep your electric bills down, too. You'll want to make sure your air conditioner, whether central air or window unit, is clean, maintained, and performing as efficiently as possible.

Can I do maintain my air conditioner on my own?

The short answer: maybe. There are simple fixes that any parent in the D.C. area should know – because if that AC breaks down, you may have a sweaty riot on your hands. At the same time, there are issues that are best left to trained professionals.

First, you need to understand that air conditioning systems have two separate components: a condenser and an evaporator. Both of these parts are sealed, so if anything needs to be done beyond the basics, you need to call in a professional air conditioning service company to perform diagnostics and repair. But you can follow certain air conditioner maintenance procedures to keep your system operating at peak efficiency.

Please Note: Before doing any work on an air-conditioning system, make sure the power to the system, both to the condenser and to the evaporator assembly, is turned off.

Routine air conditioner maintenance: The Condenser

1. Check the condenser. The condenser is the outside unit. It contains a compressor, cooling fins and tubes and a fan. You’ll want to remove any visible debris—e.g. dirt, leaves, grass clippings—from the fins. They can be vacuumed gently with a soft brush.

Take care: those fins are fragile and can easily be bent or crushed!

If you notice that any of your condenser’s fins have been bent, you’ll want to straighten them. If they’re not crushed or there are only a few damaged fins, you can buy a special set of fin combs from an appliance parts store to straighten them, or even do minor straightening with a butter knife.

If several fins are crushed, ask your service provider to straighten them during your yearly maintenance appointment.

2. Vacuum behind the fan. If you can, that is – sometimes the fan can be unscrewed, although not completely detached, for easier access.

3. Outdoor condenser? Take care of that, too. Cut back branches and any other plant life back at least two feet in all directions to ensure proper airflow around the unit.

To help keep the condenser clean during the months when it’s not in use, you can cover the top of the unit with a piece of plywood or plastic to keep debris from falling in. Don’t cover its sides, which can cause moisture buildup and eventual corrosion.

4. Is your AC on the level?  Place a level on top of the unit and see if balances. Why? It’s very important to know if the pad upon which your condenser unit rests is stable. Often, the pad begins to tilt as the soil settles, and an out-of-level condenser unit can cause the compressor to fail prematurely. Use rot-resistant shims to even it out, if need be.

Do-it-yourself evaporator maintenance

Your second stage of DIY air conditioning maintenance involves checking the evaporator, the inside component. In order to reach it, you’ll have to remove the access plate—which may be screwed or bolted— and any foil-wrapped insulation.

Always remember to make sure the power is completely off!

Once you’re inside, clean the underside of the unit with a stiff brush. If you like, you can then spray the coil with a no-rinse coil cleaner, which you’ll find at any big-box home improvement store or hardware store.

Next, clean the tray below the unit. If you see evidence of fungus or mold, use a bleach-water solution, or pour a tablespoon of bleach down the hole.

Finally, after you reinstall the access plate and tape the insulation back over it, turn the power back on, turn the air conditioner on and check for any air leaks. Seal any leaks you find with duct tape.

Calling in the professionals?

If you’re not comfortable doing your own light air conditioner maintenance, you can ask your HVAC professional to add these projects to your yearly maintenance checkup. At the very least, you can change your filter regularly—every 30 to 90 days—and make sure nothing is blocking your cold air returns and registers. If you’ve kept up with your maintenance and still feel your system isn’t working right, or if it’s making any unusual noises, call in an air conditioning professional.

Good luck! Knowing the basics of air conditioning maintenance will keep your family cool for many hot summers to come.