New one...what is this ?

[Gene South]

This small metal connection was tied into the cold water side of one of two side-by-side new water heaters in a new construction home in Prosper Texas. The device was between the cold-water inlet and the shut-off valve. The device routed water to the pan drain line See photos. (It was tied into, and downstream of, the pan drain line. It almost appeared like it was supposed to be some sort of back pressure release. The static water pressure was 115 lbs and no expansion tanks were installed, but that is another story. Oh Ye of greater knowledge.....What is this device and/or connection and what is it's purpose?

Gene

[Gunnar Alquist]

Got me... Maybe some kind of trap primer?

[Jim Luttrall]

Watts: BRV | Combination Ball Valve and Relief Valves (http://www.watts.com/pro/_productsFull.asp?catId=64&parCat=327&pid=564&ref=2)

Looks like one of these. Takes the place of a thermal expansion tank.

[Gene South]

Hi Jim, you are right, that is it. Good job.

Thanks

Gene

[Scott Patterson]

Yep, it is an expansion valve. See them all of the time in place of an expansion tank. Great little device that works well.

[David Bell]

They do work well on water heaters but don't address the pressure problems in the whole house. A pressure reducing valve should be installed at the meter. High water pressure reduces the lifespan of fixtures and devices such as auto-feed valves.