How do I thoroughly clean my central air unit coils without damaging them?

Question

Should I simply lightly spray the unit with a waterhose?

Is there some solution I can mix and spray on the unit and rinse off with a hose?

What do you recommend?

Answer 1

Look up your local retailer of Virginia condenser cleaner products. You can spray it it with a Windex bottle-like sprayer and hose out with a light spray of water. To do it thoroughly, you would have to kill power to it, take the top off and spray it from the inside out. That way it pushes any big chunks of c**p back out the way it came in. it's also a good idea to get the acorns and leaves out when you're in there. Keeping the unit covered in the off season helps cut down on the junk inside.

And be careful because the pressure from a garden hose WILL bend the p**s out of the fins.

Answer 2

Any of the hvac supply houses will have condenser coil cleaner for sale relatively cheap.  ($7-$15 per gallon)   If that's not an option for you, you can try any cleaning agent or even still get a lot of benefit by just hosing them out with plain water.  Residential water pressure typically will not flatten the fins so long as you're careful to flush the water straight through, and not at an angle.  Just be careful and be gentle at first, if you're not having a problem flattening fins, then go to it.  

You'll want to pull the disconnect, or, better yet, turn off the breaker in your breaker panel before flushing.  Once power is off, don't be afraid to give it a good soaking.  Like one of the other answerers said, it may be worth your while to try flushing it from the inside out, ..if it's not too much trouble to remove the fan shroud.

  It's a good habit to clean the condenser at the beginning of each summer, to get peak capacity and efficiency out of your unit.

Good luck.

20+ yrs HVAC tech,...Union BTJ,   Rses CM, Nate certified, Licensed Hvac and Ref. contractor, Med gas and backflow certified....and if that ain't enough, I can sing ya a tune.

Answer 3

You can get foaming coil cleaner that you spray on and it foams to remove dirt between the fins.  Just follow directions.  The pressure from a garden hose shouldn't be strong enough to bin the coils.