Water on outside of high efficiency Goodman Furnace?

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soparklion11

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My mother lives in Pennsylvania. She has consistently had water running down the outside of the exhaust pipe from her ~7 yr old Goodman High Efficiency gas furnace for the past 3-4 weeks. It is located in a 2nd floor utility room. It seems to happen regardless of precipitation. It has been too cold to even frost for the past few days, but water continues to run down the pipe. Last night I cut away the attic ceiling that had water damage - Pics 1 and 2. The pipe was wrapped in fiberglass with foil on the outside and the fiberglass was saturated. It rained here a few days ago, but I don't quote understand how it was still dripping water at least 48 hours later.

Pic 1
Pic 2
Pic 3 - Furnace setup with my 'water catcher'

She lives in a 'community' so that HOA takes care of the roof and the roofers have been trying to find a leak. They replaced a rubber boot but it was still leaking yesterday.

Any ideas as the the source of the water or how to stop it?
If anyone has any good ideas on how to stop the water from entering the furnace without continually changing out towels from around the pipe, do let me know.
At what point should we look for the roofer to repair the furnace? I'm considering having a furnace inspection to look for water damage.
 

Guzzle

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A WAG says her dew point is such that the moisture in the air is condensing on the pipe.

 

soparklion11

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Update: Online help and the information below suggests that it may be a leaky or inappropriately sized flue pipe. How can I determine the appropriate flu pipe setup in order to 'double check' the company that services it?

I have a Goodman high efficiency furnace in the utility room in my attic. There are two pipes to the roof, one is a 3" intake pipe and the other begins as a 2" exhaust pipe that then expands to a 3" pipe about 2' above the point that it exits the unit. The two may meet and leave the roof via a common outlet.

There is water pooling on the top of the furnace where the exhaust pipe connects (I have yet to look inside of the furnace). The joint of the exhaust pipe at the furnace leaks the majority of the water. Water also runs down the outside of the exhaust pipe. The exhaust pipe had insulation wrapped around it that was saturated with water and removed. Although I am catching the water with towels where the exhaust meets the furnace, there is less than 1/4" of water in the pan below the furnace.

Has anyone experienced this problem? Information available online suggests that it is condensation, possibly due to a faulty exhaust pipe installation. The humidifier could also be the issue, but it is on the other side of the furnace from the exhaust pipe. Further, the humidifier is turned off and the water flow to it has been shut off for ~2 weeks and the leak is still present when the furnace is running.
 

Guzzle

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Can you somehow divert the water with sheet metal baffles?
If it gets on internal elec. connectors you will have knotty problems. I had a connector that measured 60 megohms instead of the typical 5 milliohms.
 

BuzzLOL

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First guess is that it's leaking at the roof penetration... some ice up there melting...
 

BvilleBound

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I agree with BuzzOL. Your water problem looks like water leaking through the roof around the pipe, particularly because water was on the OUTSIDE of the pipe -- which also damaged the drywall in 'Pic 1'. That said, you should also check the combustion air pipe after it pierces the roof. It should have a 180 degree turn, to prevent water from entering the pipe. Here is a diagram from the Goodman installation guide.
 

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