What must be done to all appliances in an RV before filling it with propane?

Before filling an RV with propane, it is essential to turn off all appliances. This is crucial for safety reasons, as it helps prevent any accidental ignition or explosion during the refueling process. Propane is a flammable gas, and appliances that are still on could potentially create sparks or ignite the gas while it is being introduced into the system. Ensuring that all appliances are turned off reduces the risk of fire hazards and allows for a secure filling operation.

Though there are other important safety checks and preparations that might involve appliances, such as cleaning or checking for leaks, the primary and immediate concern during the filling process is to ensure that no appliance can inadvertently cause a fire. This step is generally mandated in safety protocols to protect both individuals and equipment when dealing with propane gas.