When should a Relief Valve on a Regulator operate?

The relief valve on a regulator is specifically designed to operate when there is excessive pressure in the supply piping. Its primary function is to prevent over-pressurization of the system, which can lead to potentially dangerous situations such as gas leaks or explosions. By opening to release excess pressure, the relief valve helps maintain safe operating conditions within the gas supply system.

In contrast, while gas being turned off or the appliance being in use are activities that might affect pressure, they do not directly trigger the operation of a relief valve. Similarly, although temperature can affect gas systems, the relief valve is not designed to operate based solely on temperature limits but rather focuses on pressure levels. Therefore, the relief valve serves as a crucial safety component to ensure that pressure does not exceed established thresholds, making the correct operation point clear.