Clearing out A/C condenser drain holes

Jul 20, 2005 10 Replies

I believe the drain holes where condensate from my air conditioner drains are plugged up. I don't see any water dripping on the ground when I run the A/C and I get a faint smell of mildew when I first start up the fan. Unfortunately, my Chilton's manual doesn't show where these holes are or how to clear them out. Can anyone give me some pointers and/or point me to a diagram on the internet?



Thanks in advance.


I had a musty smell awhile back and fixed it without any disassemble or work.

Try this first:

Close all the vents on the for the AC. Put the Fan on full. With the vents closed, the back pressure of the air may very well blow the drains clear.

I also poured some bleach down there to kill the mold and muck.

Oh yes, I also believe you need it on reticulate.

Bleach is a bad idea. Residue may damage coils. Lysol spray is better choice or purchase foam designed for the purpose from car dealership. I am surprised that back pressure could clear it.

I'd be worried about using bleach, especially when your drains are clogged, unless you enjoy the smell of bleach :) There are commercial products made specifically for this, you dump it down the vent intake in front of your windshield. As for locating the drains, can't help you there....

Interesting idea. I tried the back pressure technique, but unfortunately, it didn't work for me. Any other ideas on how to locate and clear the drain holes?

Didn't see what model is being discussed - when I drove a 97 I pulled the blower motor (3 screws) and poured a little water down the ducting from the motor location towards the condenser housing and it dribbled out in the engine bay from a black rubber L-shaped do-dad located low on the firewall about midway. When I had the warm and fuzzies it was draining, I sprayed some (a lot) of anti-bacterial windex down the same vent. It worked for a long while. I also paid to have it down at the dealer - lasted maybe a little longer and smelled a lot cleaner (don't know if that was just fragrance or the dealer did a more thorough/better job).

Now that you mention Lysol, It was indeed what I put down the vent, Not Bleach. It had been long enough since I did it, that I forgot.

Possible fix:

What is very common is that the condensation from your vehicles evaporator is NOT leaking out from the bottom of the black plastic housing that has the evaporator inside. There is a small drain HOLE or small drain TUBE that is located under the evaporators black plastic housing that is PLUGGED UP with leaves, debris, etc,etc.

You need to take somethin SOFT such as a plastic soda straw and climb under the vehicle with a flashlight and locaate this HOLE or TUBE. It should be about the size fo yout little finger. Insert the SOFT PLASTIC straw up into this HOLE or tube and you will wind up with a WET HAND and armpit. NEVER EVER use a SCREW DRIVER or a STICK as you can poke a HOLE in the aluminum evaporator and you will be spending $400.00 to have it replaced.

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