The main relief valve location relative to the pump is on which side?

The main relief valve location relative to the pump is on which side?

• A. Suction side
• B. Discharge side
• C. Inlet side
• D. Outlet side

Answer: (B)

Relief valves protect the system by sensing pressure after the pump and dumping excess flow to prevent overpressure. Placing the valve on the discharge side means it can respond to the actual pressure being produced by the pump and protect downstream piping, valves, and equipment. If it were on the suction side, it would relieve pressure before the pump, which could cause loss of prime, cavitation, and would not relieve the pressure where it could cause damage. Inlet and outlet terms refer to the same sides, but the critical point is that the pressure needs to be controlled after the pump, so the discharge side is the correct location.

Relief valves protect the system by sensing pressure after the pump and dumping excess flow to prevent overpressure. Placing the valve on the discharge side means it can respond to the actual pressure being produced by the pump and protect downstream piping, valves, and equipment. If it were on the suction side, it would relieve pressure before the pump, which could cause loss of prime, cavitation, and would not relieve the pressure where it could cause damage. Inlet and outlet terms refer to the same sides, but the critical point is that the pressure needs to be controlled after the pump, so the discharge side is the correct location.