Water tank valve

[pmassie]

Have you ever seen a water tank safty valve connected to the hot water line

Like the drawing a just made...

[Jeffrey R. Pope]

Yes.

Was it a pressure-relief valve, or a combination temperature-pressure relief valve?

If it's a TPRV, the sensor must extend into the top of the tank (generally) a minimum of 6 inches.

If it's a PRV, it may have been used in conjunction with a Watts 210 gas shutoff valve.

Do you have any additional information or actual pictures?

[pmassie]

cant fid a pic but it's really a pressure-relief valve

[pmassie]

OK..the valve is not independent, it is connecteted to the hot water line

[Jeffrey R. Pope]

There is no issue with having a PRV on the system. The question is - was over-heat and over-pressure protection present on the tank?

The diagram you have posted is insufficient to determine if the tank is properly protected.

[pmassie]

ok..
-valve installed = yes
-is tank protected = yes

if the pressure goes up will it activate the valve or go through the hot water line. to me a set up like that , where the pressure could go up the line doesnt make sense

[Jeffrey R. Pope]

What type of protection was provided for over-temperature?

[Roy D. Cooke, Sr]

http://www.factsfacts.com/MyHomeRepa...sureRelief.htm

http://www.safteng.net/Accident%20Ph...0explosion.htm

http://www.theplumber.com/explodingwaterheater.html