Where shall the main burner of a gas fired boiler have an approved manual shut off valve installed?

The main burner of a gas-fired boiler must have an approved manual shut-off valve installed downstream of all controls. This placement is essential for ensuring that the valve operates safely and effectively, allowing for the isolation of the burner from the gas supply without interfering with the operation of other control mechanisms.

By positioning the valve downstream, it provides a layer of safety by confirming that any control systems—such as safety shut-off systems and pressure regulators—can still function appropriately without being affected by manual interventions. This arrangement allows for maintenance and service work to be done safely, ensuring that the gas flow can be halted as needed while still preserving the integrity of the safety systems that monitor and regulate the burner operation.

Additionally, it helps to avoid any potential issues that may arise from shutting off the gas supply too close to the burner, where pressure changes could cause erratic behavior or incomplete shut-downs. Thus, ensuring the valve is installed downstream supports best practices in gas boiler installations and enhances operational safety.