New construction

[Bruce A. King]

Many will know what is shown here but I wanted to post this for those that do not.

There are two extra features plumbed in, do you know what they are?

The flex copper is the cold water to a water heater.

[Brian E. Kelly]

Nice pic Bruce

[cjustason]

Possible water hammer arrestor might be the brass but never seen it on plastic piping. If that's so the other line would be pressure relief. However you could have a water heater return loop.

[Sean Fogarty]

I personally would be curious of the affects of the plastic pex pipe against the flue.

[Bruce A. King]

Not a flue, just a makeup air vent to the attic.

The on/off valve has a pressure relief built in for thermal expansion with the discharge going down to a floor drain.

The device on the right is a trap primer that is activated by random small variations in the water pressure.

[Joe Funderburk, CMI]

Bruce, the device on the right is a trap primer that is activated by random small variations in the water pressure.

[David P. OKeefe]

Originally Posted by jfunderburk

Bruce, the device on the right is a trap primer that is activated by random small variations in the water pressure.

I agree with Joe.

[Tim Larsen]

Trap primer?
New to me. What's it do?

Tim

[Bruce A. King]

Some slab houses, this one is a 4-unit condo building, have a floor drain in the closet where the water heater and furnace are located. A p-trap is located under the slab and will dry out during the months where no condensate is discharging into it. The trap primer should send enough water to it to prevent sewer gasses from escaping.

[Joe Funderburk, CMI]

Originally Posted by bking

Some slab houses, this one is a 4-unit condo building, have a floor drain in the closet where the water heater and furnace are located. A p-trap is located under the slab and will dry out during the months where no condensate is discharging into it. The trap primer should send enough water to it to prevent sewer gasses from escaping.

Bruce, is that the solution to stinking laundry rooms when the floor drains dry out? How would you retrofit an existing laundry room floor drain to keep it primed?

BTW, I don't see a drain at the thermal expansion valve. Is it a small Tygon tube? If so, I didn't see it.

[Bruce A. King]

The drain pipe is pex, under the green valve.


Are you talking about old houses that have the laundry floor drain going to the waste? You just need a water supply and a trap primer as shown above. I guess you could put a y-adapter of some sort on the washer supply for the trap primer.

[Tim Larsen]

Thanks, Bruce. Learn somethin' new every day in this business.

Tim