DIY Tips for Cleaning Your AC Condenser

Because the AC condenser is located outside, dust, pollen and other environmental contaminants can collect on the coils or fins and cause it to lose efficiency, cooling effectiveness, and can even damage the compressor. We generally recommend cleaning your condenser coils once per year. Coils may need to be cleaned more or less frequently depending on the location and environmental factors, but we would not recommend going more than two cooling seasons without a thorough coil cleaning.

Cleaning an air conditioning condenser is not rocket science, but there are a number of different ways to get in trouble and cause damage to yourself or your condenser. If you must be a do-it-yourselfer, do yourself a favor and read the Operations and Maintenance Manual for your unit before you start. If you can’t find the hard copy, most manufacturers have downloadable copies of their manuals online, listed by the model number of the unit which is located on the nameplate of your condenser. After you’ve read the manual for your unit, check out these tips.

Here are some tips on how to avoid regretting your decision to be a do-it-yourself HVAC tech:

1. Read the manual. I know, I said this already, but it’s really that important. Reading the instructions is not a sign of weakness. Take the time to do it right and you could save yourself a lot of money and headaches.

2. Never, never, never use a power washer on your condenser.  Put down the power washer and step away from your condenser! Power washers are great for a lot of tasks, but cleaning your AC condenser is not one of them. A power washer can bend and damage coil fins and restrict air flow to the point of inoperability. See photo below.


This is not a happy AC condenser. The power washer has almost completely cut off air flow through coils.

3.  Avoid coil cleaners when possible. Coil cleaners can be harsh on you and your coils. Many coils can be cleaned with nothing but a coil brush, shop vac and a garden hose. If coils do not get sufficiently clean with water and brushing, then try a commercial coil cleaner. The best way to know if your coils are clean and your unit is operating at peak efficiency is to test the temperatures and pressures of the refrigeration circuit with a proper set of gauges.  We recommend a professional HVAC technician for testing unit operations.

4. Know your coils. Some coils are one piece, some are two pieces laid back-to-back. The two piece coil needs to be separated in order to get them clean or you’ll just clog up the middle of the coil worse than if you didn’t clean at all. In addition, some coils are coated, some not. If they’re coated, you need to know what type of coating and what cleaners are acceptable to use on that particular coating. The wrong cleaner can damage the coating or even the coil itself. You’ll find this information in – you guessed it – the O&M manual.

5. Read the Directions. If you need to use a coil cleaner, read the directions to make sure that you protect yourself (gloves, eye protection, etc.) and your coils (is it safe for your type of coil?) appropriately. Also make sure you are using a CONDENSER coil cleaner. A split unit has both a condenser coil and an evaporator coil. The cleaners are NOT interchangeable. Using the wrong one can damage your coils.

6. Safety First. Use safety glasses to avoid getting debris, cleaner, etc. in your eyes. You only have one set of eyes. Protect them! Also use gloves to protect your hands when cleaning the coils. Coils can have sharp edges. Wouldn’t want to mess up your manicure, would ya?

Although I preceded this article with the statement that coil cleaning is not rocket science, I would also like to point out how many times in this article that I said some version of, “If you do this wrong, it could damage you or your coils.” For this reason, I would always recommend using a professional HVAC technicians, and not just because I am an HVAC contractor. There are a lot of ways to go wrong with HVAC units. They are complex and a lot more delicate than they look. When you look at it as protecting your investment, it just makes sense to find an HVAC professional that you can trust, and use them. If you don’ t already have one, call us at Advance Air. We’ll take great care of you and your coils.