Might be old hat to some...

Some one did not have a clue what they were doing looks like a home owner job to me the small pipe protruding from the side is designed for beneath the roof or the interior of a basement where exhaust and combustion air enter the pipe within a pipe design let me go get my camera and take a picture of one dissembled and let you see how they are suppose to look.

Here is what they look like disassembled just happen to have one;);):wink:

Charlie, I think that make sense now.

Never seen that set up.

Kevin’s install used the wrong parts as the wye is not supposed to end where it does in his photo. Right?

Right:shock:

So the “y” is really serving no purpose. Other than a shoddy homeowner job, would you call it dangerous? They may have used the wrong parts but would you still consider it safe?

The bottom 90 that turns down is the combustion intake the 90 that turns up and connects into the wye is the exhaust from the furnace and travels throught the wye and out the center pipe at the top. The take off of the wye is doing nothing the combustion intake was suppose to be connected at that point. You said the square vent to the left is a HW heater exhaust vent is this correct. If so It would make me no difference if it was a HW heater exhaust or a dryer exhaust it apears to close to the intake on the furnace. I would ask for the whole mess to be removed and installed with MFG installations instructions.

Thank you for your help Charley. It’s greatly appreciated.

I would say that they found that they could not get through the wall where they needed it to look up to the device.

If it were me, I’d have cut off the device and use it on another job.

Actually, I believe they are using it as a muffler. The buyer said the seller’s neighbor filed a noise complaint and he thought the extension was installed to muffle the noise it previously produced.

If they separate the intake and the exhaust too far from each other and the two end up in different pressure ‘zones’, the pressure switch will not prove and the furnace will fail, probably intermittantly (when the wind blows). Interesting on the noise complaint, I wonder if there really was a noise issue…