Pull The Condenser Top

The photo above is from a video one of my techs took of proper condenser cleaning. I must say, he did a GREAT job of cleaning the coil, and he was very careful with the top. However, I STILL would have liked to see him pull the condenser top completely during a full maintenance procedure. Pulling the top usually just requires disconnecting the fan wires, cutting a few wire ties, taking out some screws, and then removing the fan grille or the entire top and laying it top-down in the grass.

That is ACTUALLY how I performed maintenance, even before I started my own business.

Here is why:

• If you wash from the outside in, you are not doing the best possible cleaning. Washing from the inside out is a superior method of cleaning.

• If you lay the fan on top of the unit (as shown above), you risk twisting/damaging the wires, scratching the paint, and bending the fan blade.

• When you pull the top entirely, you can more easily clean the dirt and leaves from the inside of the condenser; this should also be part of a proper maintenance procedure because that dirt can reduce coil capacity and hold moisture against the base, compressor, and accumulator. That moisture results in corrosion.

• With the top off, you can get a better view of any wire rubouts or potential wire rubouts. You can address them before they cause a problem.

• You can also visually inspect the compressor terminals for signs of heat and corrosion. That way, you could potentially prevent a major issue such as a terminal failure or “blowing a terminal.”

Obviously, the maintenance will take about 5 minutes longer. You will also need to rewire the components properly with the terminals snugly installed.

So, what do you think?


P.S. – Here is the video in case you want to see what I mean, and yes… he knows that cleaner isn't always required when washing a coil, but he used it for demonstration purposes. (To learn more about the different types of cleaners, check out THIS article.)

P.P.S. – You can also watch a more recent video about Bert's top tips for a maintenance procedure HERE. A tech tip based on that video is also available HERE.

Related Tech Tips

Negative Superheat? Time to Check Your Tools
I was fresh out of school, working as an apprentice at my first real HVAC job, and I was listening in on a shop conversation between a few techs. They were talking about finding so many overcharged systems. One of the techs turns to me and says, “I had a unit yesterday that was so […]
Read more
An Argument for the Trades as a Viable Career Path
  “What do you want to be when you grow up?” “Where will you go to college?” Young people hear those questions all the time. Although we ask those questions in good faith, they also carry a burden of expectations.  By asking those questions, we imply that we expect the children to go to college […]
Read more
Crankcase Heaters and Single-Pole Contactors
We keep two-pole, 40-amp 24v coil contactors on all of our vans. They are versatile and reliable, and you can replace most residential A/C contactors with them. There are a few things to watch for, though, especially when you have a crankcase heater. Many brands power the crankcase heater constantly and shut it on and […]
Read more

5 responses to “Pull The Condenser Top”

  1. Completely agree with your procedure. Without top removed very unlikely a complete vacuum of bottom of outdoor unit occurred, thorough vacuum/clearing all drain holes, and thoroughly inspecting the compressor and, if ASHP, the RV for wiring/pipe issues and the accumulator (typically). Please keep preaching/teaching the proper sometimes more tedious procedures. Thanks.

  2. can you do a video on how to clean a double coil on a roof top unit. I am a one man show and want to see if you have any tips I could use. thanks !!

  3. I agree with this. Some commercial units, the tops can be removed or access panels removed to clean coils better. I never thought to use a vacuum on the bottom basin. This is a good tip. I would like to see tips on indoor coil cleaning/inspection and so forth.

  4. A wise man once told me, since the fan is pulling air/debris from the outside in, always clean with water from the inside out. This is most effective in removing dirt and debris from the fin area. It always makes me nervous to see people when they try to clean with a fan motor and blade balanced so precariously on top. Although I must admit I have come across several units that there is so little slack in the wiring the top could barely be removed without first disconnecting the wiring.

Leave a Reply

Your email address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.


To continue you need to agree to our terms.

The HVAC School site, podcast and daily tech tips
Made possible by Generous support from