Water heater direct-vent vibrations

[ning]

Our house has a (propane) power-vented water heater - there's a fan mounted on top of the heater which sucks air and cools the exhaust, which blows into some 3" black pipe up to the ceiling etc.

Anyhow, vibrations from the fan go right into the pipe, which is solidly attached, and thence into the ceiling joists which it's probably attached to above (and that's almost right below our bedroom).

I'd like to cut a chunk out of the black pipe, and use some sort of (silicone?) rubber coupler to keep the vibrations from traveling up the pipe. Anyone know of something appropriate for the part? There is heat in the exhaust, though not a lot; I'd like to stay within code for the application.

 

[Raspy]

Yes. The rubber pipe section is called a "Fernco". An EPDM rubber hose designed to fit over, and clamp to pipe. Typical WH exhaust is either 2" or 3" pipe. Either a measurement of about 2 1/4" or 3 1/2". Find out which one you have and go to a plumbing supply and ask them for a 3" or 2" Fernco. They have a stainless band clamp on each end. 3" ones are about 7" long. Cut a section out of the exhaust pipe you have, about 2" shorter then the Fernco. Slip it into place and tighten the clamps.

It might also be that your fan is failing. Usually the fans are very smooth running. You said vibration, but maybe it's just telegraphing noise.

 

[Tractor Seabee]

Our house has a (propane) power-vented water heater - there's a fan mounted on top of the heater which sucks air and cools the exhaust, which blows into some 3" black pipe up to the ceiling etc.

Anyhow, vibrations from the fan go right into the pipe, which is solidly attached, and thence into the ceiling joists which it's probably attached to above (and that's almost right below our bedroom).

I'd like to cut a chunk out of the black pipe, and use some sort of (silicone?) rubber coupler to keep the vibrations from traveling up the pipe. Anyone know of something appropriate for the part? There is heat in the exhaust, though not a lot; I'd like to stay within code for the application.

How old is the WH? Is this a new occurrence? Or is it something always there but getting irritating? Those heaters are usually pretty vibration free. The above answers may open some new responses. Like is the condensate draining out?

Ron

 

[Raspy]

Ron,
The OP is describing a power vented exhaust, not a condensing unit.

 

[boggen]

pictures?
make/model of WH (water heater)?

 

[Tractor Seabee]

Ron,
The OP is describing a power vented exhaust, not a condensing unit.

I may have mad a wrong assumption. If the black pipe the OP describes is ABS; then, it may be a condensing type heater. The information provided was sketchy at best; hence, the questions.

Ron

 

[ning]

Believe it or not, the vibration has been there since installation. It bothers me to varying extents, and I've always had things much higher on my "to do" list to bother with it. At its worst, it's a minor annoyance really as I only notice it when I'm in bed and the thing comes on, which is almost never.

I've attached a pic of the top of the heater & vent setup.


The water heater is a State Select 75. It's not made any more. The installation is about 20 years old.

 

[dodge man]

Until we installed geo-thermal, we also had a similar issue. I just lived with it but it was a little annoying at times.

 

[ning]

Yes. The rubber pipe section is called a "Fernco". An EPDM rubber hose

That looks reasonable; my question is, is it appropriate for the heat? The vent isn't hot (being mixed well with cooler air) but it's definitely warm.

The water heater is an older (~20 years old) State Select: SS8-75-PQVT1. I can't find data on it on the net unfortunately, I'd like to see installation specs.

 

[Raspy]

The Fernco will take more heat than the ABS black plastic vent pipe. So, yes.