Domestic water supply system & Pressure Relief Valve

[Marc Morin]

A pressure relief valve (or expansion tank) is required if the home has a pressure regulator or other device that closes the loop...does the pressure relief valve at the tankless water heater meet that requirement or must another PRV be installed at an exterior location?


Thanks

[Tom Rees]

Two different beasts Marc. Here is some good info on expansion devices. I almost always see them installed just above water heater on the cold water supply line. Their main job is to protect against thermal expansion as water is heated. Hope this helped. Thermal Expansion - Learn About - Watts (http://www.watts.com/pages/learnAbout/thermalExpansion.asp?catId=64)
or http://www.aohomeinspection.com/pdf/Thermal-expansion-control.pdf

[Daniel Mack]

Two different beasts Marc. Here is some good info on expansion devices. I almost always see them installed just above water heater on the cold water supply line. Their main job is to protect against thermal expansion as water is heated. Hope this helped. Thermal Expansion - Learn About - Watts (http://www.watts.com/pages/learnAbout/thermalExpansion.asp?catId=64)
or http://www.aohomeinspection.com/pdf/Thermal-expansion-control.pdf

Excellent information source. Thanks!

[Loren Sanders Sr.]

Two different beasts Marc. Here is some good info on expansion devices. I almost always see them installed just above water heater on the cold water supply line. Their main job is to protect against thermal expansion as water is heated. Hope this helped. Thermal Expansion - Learn About - Watts (http://www.watts.com/pages/learnAbout/thermalExpansion.asp?catId=64)
or http://www.aohomeinspection.com/pdf/Thermal-expansion-control.pdf

My water district states that only older water meters contain check valves built in to the meter...he indicated older as 25 to 30 years old homes.