What must be done to appliances after the piping system is placed in operation?

Purging is a critical step that must be performed on appliances after the piping system is placed in operation. This process involves removing air from the gas lines and ensuring that the system is fully charged with gas. If air is allowed to remain in the lines, it can lead to incomplete combustion, which not only affects the efficiency of the appliances but also poses safety risks, such as the potential for explosions or releases of harmful gases.

Purging helps establish a stable and safe environment for the appliances to operate. It ensures that the gas supply is pure and free of any contaminants that could interfere with appliance performance. By effectively purging, you also prevent issues such as delayed ignition, which can be hazardous.

While calibrating controls, testing efficiency, and replacing filters are all important maintenance practices in their own right, they are not immediate steps that must be taken right after the piping system becomes operational. Thus, purging the appliances stands out as the necessary action to prepare them for safe and efficient operation.