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Why is water dripping off the coils

790 Views 11 Replies 5 Participants Last post by  beenthere
My AC unit's coils are dripping directly down instead of following the surface to a channel at the low end that leads to a drain. I watch it happen, and have put a plastic bin below it to catch the drips... they fall directly down from the veins in the coil. Two days can produce over a gallon. The unit was not designed to account for this kind of dripping. is something wrong with it? included a pic, but the coils are older now.

I think I will just staple plastic to the walls of the intake and install a makeshift drain tube at the center to carry the water to the drain on the other side of the register wall. I have some coil cleaner, but am nervous about damaging the coil.


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The air handler should be sitting level or slightly towards the left> drain.

If it is sloping right then maybe gravity is causing the water to drop.
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dirty coil also may interfere with proper drainage.
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Dirty coil or not level as have been mentioned. Also it will be more likely to drip with the end plate off... does it drip otherwise?

BTW, looks like the installer had fun brazing the lines without a heat shield to protect the innocent bystanders! :wink2:
Hi, it drips from everywhere on the coil. Anywhere there is condensation. From the middle, from the quarters. Drips straight down. Thank god I figured this out before it got bad. The whole floor and ceiling below me would be mush by now.
Is it cooling your house properly?

If it is low on freon and the coil freezes then when it defrosts it will drip down.

Have you had it serviced and the freon level checked.

Get the tech to check the airflow thru the coil.

If the fan is sucking too hard and the velocity of the air is too high then it can interfere with the drainage.

Usually that is caused by too small ductwork or using a highly restrictive air filter.

Try use a Merv 7 or 8.
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When it's low on refrigerant, freezing will start from one side of the coil.

I would shine a light through the coil and check the other wise to see if it's clean. The surface can look clean but can still have dirt embedded inside.
That looks like a double gutted coil being fed at top and bottom. I doubt low refrigerant is the problem but still possible. I think more likely the coil is partially plugged so shine a strong light through it as suggested to see what you can see.

Since we recently had a poster who mounted his furnace upside down please tell us this is an upflow system. I don't me to insult you, just need to cover all the bases.
Slope coils are critical when it comes to condensate flow. I had one that dripped water because the customer had shot some WD-40 on the blower bearings while it was running... actually I suspected that but didn't accuse him of it. It was pretty obvious from the looks of the area around the blower.

Anyway, the call was for leaking water from the ducting. I cleaned the evap coil and it went back to "draining not raining." Oil and slope coils don't play well together.

Sometimes a coil will get oily from a refrigerant leak and after a few years start dripping oil. If you have had to recharge your system annually, that oils buildup is another possibility for the raining.
I am using higher merve filters due to the dust and allergies that we experience. The coils could probably use a good cleaning. they look oxidized or something.
Did this unit drain properly before? If yes, i don't think it's related to slope unless whatever it's sitting on shifted.
Has the blower motor been slowed down due to noise.
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