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Author:
Steve9358 (FL)
I have three pipes that comes out of the wall behind my hot water heater. The first two pipes are the cold water supply and the hot water return. Third pipe is my problem.
Here are a few facts about the mystery third pipe:
It is located about one foot below and in the middle of the other two pipes
It is the exact type (CPVC) and size as the other two pipes
It is open ended. No cap or cover on the pipe
It is exactly in line with the high pressure relief valve as if it was once piped together
I am going to try to add a picture below:
The pressure relief valve currently has the same type and size piping running from the valve to outside. I am not the original owner of the house so I do not know if the original tank was piped into this third pipe and a replacement installer converted the pressure relief pipe to run outdoors.
I have put a small amount of water down the third pipe and do not see any water stain on either side of the wall. I have put compress air down the pipe. It does pull a vacuum similar to a drain.
I want to install a hybrid hot water tank that requires a drain line for condensate. I would like to use this third pipe if it is in fact a drain.
Anyway, I can not tell what this pipe is without opening up the wall.
Does anyone recognize the pipe and its purpose? Any suggestions on how to determine its purpose?
Thanks,
Steve
Edited 3 times.
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Author:
hj (AZ)
Tun water into the pipe until it overflows or the water appears somewhere. THEN you will know if you can use it for the drain line.
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Author:
Steve9358 (FL)
I spoke with two plumbers. They told me that the third line is there for the high pressure relief value. It was the way they did it in 1997 when the house was built. The line is either connected to a drain line or run outside from under the slab. I will be able to use it as a condensation drain line.
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Author:
juca01 (FL)
Hi Steve,
I had the exact same question and for the same type of project. Thanks for adding your conclusions. I was wondering how did the installation go on the new hybrid system and if the middle lower pipe did happen to go to a drain somewhere safe. I am planning on replacing my aging water heater with a hybrid WH as well.
Thanks,
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