Heat trap fittings

Robert O'Connor_3

http://www.rheem.com/consumer/catalogRes_detail.asp?id=78

Came across these while looking up water heaters. Don't see why they wouldn't work with an indirect. Just wondering if they realy work and would save on building a thermal trap off an indirect or are they just something else to leak/jam up.

Matt Undy

I installed a water heater which had this type of heat trap installed at the factory a few years ago. They certainly dont'work perfectly because the cold water line passes through above the tap down to the water heater and warm water comes out of the cold faucets further down the line. It may be less than with the old heater without the heat traps.

A more serious problem than thier marginal heat traping abilities is that they make knocking noises when a fixture is turend off, as the shock in the water in the system "bounces" bewtween the various air chambers in the system. It also occurs even as pressure in the street main chnges a small amount, even is no water is utilized in the house. Even the feed to a Honeywell flow through type humidifier is sufficient to cause the knocking when it shuts off. This noise isn't particularly loud, but I would select a pip heat trap arangemnt over the mechnaical device.

Kal Row

i also could not find the cv rating for it

i doesnt look good - not a prolem for DMHW - there is plenty of head avail from the public water works - but for a multi zone hydronic system the CV sould be a real issue