What is the purpose of a discharge pressure relief valve in a fuel oil pump system?

The purpose of a discharge pressure relief valve in a fuel oil pump system is primarily to protect the system from excessive pressure buildup. This is typically achieved by allowing excess fuel to flow back to the tank when needed, ensuring the system remains within safe operational limits. When there is a scenario in which the flow of fuel is restricted or shut off, the relief valve opens to divert the fluid back to the fuel tank. This prevents potential damage to the pump and associated components due to overpressure, which can lead to catastrophic failures if not managed properly.

While other functions might seem relevant, they do not align with the core purpose of a discharge pressure relief valve. For instance, preventing overheating of the oil is primarily managed by temperature controls, not necessarily by a relief valve. Filtering impurities is the role of a different component, usually a filter or strainer in the system. Regulating pressure in the discharge line is close but generally refers more so to control valves that modulate flow rather than a relief valve's primary function of relieving excess pressure.