Mildew smell when cold ac on.

Not in the new car but an older car. I figure this is a universal problem. Its not a strong wretched smell its just an annoying smell anytime the cold
ac is on. I notice this in some cars..
How can that be remedied?
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Yeah.
The reason why there is a mildew smell is that there is mildew growing in the ventilation system. There's a hole in A/C system where the water that condenses as the air goes through the A/C system to get cold. The hole is clugged.
You need to unclog the hole. How? Stay tuned! I don't know. But someone else will.
Jeff
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They sell "Non-acid, foaming, self-rinsing" AC evaporator coil cleaner sprays for air conditioners that will solve this problem - one popular one is BG Products "Frigi-Fresh" sold to mechanics, there are other brands that are sold to the Wholesale AC & Appliance Service trade but it's the same basic stuff.
You have to spray it into the air intake duct right at the front of the heater box so the foam works in the right place, on the front face of the evaporator core - the part that gets cold... So a mechanic (or you if you're brave) will need to know where to drill a little hole in the heater box or the air duct on the intake side, stick the extension tube from the cleaner can in the hole and spray in a controlled dose of the cleaner, then insert a plastic plug in the hole for next time.
Give the cleaner 15-30 minutes to soak into the crud (or follow can directions), then go take a long drive with the AC on and the dampers set to "Fresh/Outside Air" to start the rinsing process.
(When set to Outside the air will be more humid and create more condensation on the core than the Recycle air that's already been through the AC system a few times and already wrung dry.)
That cleaner should also dissolve and flush away any moldy slime growing in the bottom of the heater box that can clog the condensate drain hose - the spot where you're /supposed/ to see the clear condensate water dripping from under the car when the AC is used.
--<< Bruce >>--
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it happened to my 1991 Previa on trip to Florida few yrs ago. Interior of the van was also flooding :) I crawled under the car and blew thru that short black hose/drain sticking out off underbody. Lots of dirty water got drained afterwards. No problems since then. P.S. Naturally, I felt compelled to rinse my mouth with a decent amount of (good brand) whiskey after the fix-up. Just for healthy mouth and general hygene..... kd
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And to help you forget the taste?
Anyway, just for future reference, if you go to a garage, they are able to blow out the hole with compressed air. The whiskey tastes much better.
Jeff
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On Fri, 11 May 2007 02:13:55 +0000, Go Mavs wrote:

Water didn't drain out during AC use, it stagnates, clean the air box/ exchanger.
--
Leythos
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Go Mavs wrote:

Clean the drain tube as Jeff mentioned and then wash it out with a mild water and bleach solution.
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NO!! This is one time where experimenting with home remedies is a very bad idea.
You have to be Very Careful what chemicals you put in there - the evaporator core is made of aluminum tubing and fins, and the wrong chemical will eat a hole right through it and cause a leak. Bleach and chlorine solutions are very reactive with aluminum.
Then you get to find out what real fun (and expense) is when you have to change the evaporator core.
--<< Bruce >>--
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Bruce L. Bergman wrote:

Relax Bruce, It's ok to use as long as you mix a weak solution and flush it with water. Some of the commercial stuff like you mentioned is at times a bit harsher on fins than water and bleach, depending how you mix it. They work by actually attacking and etching the aluminum, and in untrained hands can do some real damage as you mentioned. I have used both, and for cars, as I mentioned, mix a MILD solution. I guess I forgot to post to not let it remain for a long period of time on the component, and flush with copious amounts of clean water. My mistake, sorry. OBTW, if you really want to see some reaction, try cleaning hardened concrete from aluminum tools using muriatic acid. That is the type of reaction you don't want on thin aluminum.
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Bruce, I had that problem at one time. Turned out the evaporated was not draining and it was pouring into my 95 ford escort station wagon passager sid floor board. Evey time i would turn on the air......the floor would get wet and the mildew smell would set in.
All we had to do was fix the evaporater drain tube..you see it only can out about 1/4 out of the firewall and was pour down and some how got into the car and as the water set in there it became mildewy.
Maybe that might help you ............. not sure
Trish http://www.herbalsunlimited.com
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Run the AC on recirc mode and spray an anti-mildew product into the return grill, WBMA
mike

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