Relief valve sizing

[77mccoy]

what is the proper way to size a relief for a home hot water heater 50 gallon gas 150000 to 180000 btu/hr input. Need a #/hr calculation with a set pressure of 75 psig

 

[chicopee]

Your relief valve relieving capacity will be in Btu/Hr and not in Lbs/Hr. It rating will be the unit's heat input. You should also have a temperature and set pressure ratings for a hot water heater.

 

[GenB]

if you must, calc the amount of water that can go through he orifice and mult by the weight of the water= pph or lbs/hr is the result