The 24 Volt Interlock System provides a solution to the Australian Standard (AS5601) requirements when installing an Excelsior Rangehood above a commercial gas appliance in residential premises. The gas solenoid valve supplied must be in the gas supply piping to the gas appliance. Once installed, and connected to the controller, the solenoid valve will be energised, allowing gas to flow only when the rangehood exhaust fan is running.Typically this controller would be fitted when a gas barbecue approved for commercial use is installed in a residential alfresco area under an Excelsior BBQ Rangehood.