Chilled Water Return PIping - Pressure Relief Valve

[Indumathis]

Do we need a pressure relief device on a 0.5", 1.5" or 2" chilled water return line? The chilled water line is connected to a heat exchanger.
I got a comment from one of my collegue that these are exempt from ASME...please advise.

 

[LittleInch]

Exempt from what and what code? So long as your return piping can't be isolated then it should be protected by the pressure relief in the rest of the system. If it can be isolated then you need to look at the locked in sections and see if there is a possibility of thermal load or perspire load which would overpressure your pipework.

Its a bit of a vague question so I'm afraid it got a bit of a vague answer...

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