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Strange Noise From Air Condition

I have a 2004 Honda CR-V. While the air conditioner seems to be working fine, I hear a strange noise whenever it is on. The noise is hard to describe, but sort of a very faint fluttering sound. Also, when I stopped today, a little bit a condensation came out of the vent. I looked under the car, and water was dripping from under the engine area. I know nothing about cars, so please let me know how alarmed I should be before I take it in for someone to look at it! Thank you!

Water is supposed to drip on the ground while the AC is operating and/or after you park the vehicle. It’s condensation from the AC evaporator (the part that cools the air).

If the air is your area (Charleston?) is very humid a bit of vapor coming from the vents now and then is not out of the question. Running the AC on “recirculate” may help minimize this.

So far there is no cause for alarm.

Where does the fluttering sound seem to be coming from? Is it from the vents or from under the hood?

It sounds as if it is coming more from the vents, or at least more from inside of the car.
Thank you for your help!

As mcparadise stated, it is normal–and vital–for your A/C condensor to drip water as it removes moisture from the air in the car.
You never noticed this normal behavior previously?

As to the noise, I can tell you that about 2 months ago I had the same sort of noise coming from my A/C for the first time. After 2 days or so, a fragment of thin foam came shooting out of one of the vents, and the noise disappeared. I believe that, as the car ages some of the materials in the ducts or surrounding the A/C filter may deteriorate and come apart. At least, that is my theory.

My A/C continues to operate normally, a couple of months after this incident. I don’t worry about my A/C, and I suggest that you do the same unless some other new symptoms come about.

The flutter noise could be a small piece of debris trapped in the blower (fan). The fan in your CR-V’s HVAC system is a squirrel-cage type fan, and if something gets stuck in it, or rubs up against it, it makes a flutter, or sometimes a clicking noise, depending on what’s stuck where.

Does the flutter increase and decrease with fan speed? If so, it’s more than likely something stuck in there. These small objects often get expelled or wear away in a short time and the noise goes away.

I wouldn’t worry about it unless it gets louder or the AC starts to act erratically.

Thanks!
I know - I sort of knew in the back of my mind that the dripping was okay, but I started to freak and worry about everything when I heard the noise! How embarrassing! I am calming down now after hearing from you guys, though!

Don’t be embarrassed. Better to ask than to ignore a strange noise until something goes “Bang,” which is what too many people do.

It seems to increase/decrease with the car speed. I couldn’t really tell a difference with the fan speed, except, of course, that the noise stops completely when I turn the fan off. I will try listening again. Everyone does seem to be on the same page, which is a huge relief!