A gas valve with 100% shut-off indicates what about the gas flow?

A gas valve with 100% shut-off indicates that the gas supply to the burner is completely turned off. This means that there is no gas flow to any part of the system, including the pilot light and the manifold, which is responsible for distributing the gas to the burner.

This feature is particularly important for safety, as it ensures that in the event of a malfunction or leak, the gas flow can be entirely stopped to prevent any hazardous conditions. It allows for maintenance and service work to occur without the risk of gas leakage.

By achieving a total shut-off, it guarantees that no gas is present in the combustion area, reducing the risk of unwanted ignition and ensuring that the system can be worked on without concern for gas exposure. Thus, when a gas valve has 100% shut-off capability, it signifies a complete cessation of gas supply to all components reliant on gas flow.