Installing an automatic gas shut off valve is a wise decision that can help keep you and your family safe in case of a gas leak. There are two main types of automatic gas shut off valves: seismic or earthquake-actuated valves and excess flow valves. While both types of valves serve a similar purpose of automatically shutting off the gas supply in the event of a gas leak, they operate based on different principles.
Seismic or earthquake-actuated valves are designed to detect seismic activity and shut off the gas supply in the event of an earthquake. These valves are particularly important in areas with high seismic activity. Seismic valves are designed to detect the unique frequency of an earthquake and are sensitive enough to differentiate it from other vibrations, such as passing traffic. The valve will automatically shut off the gas supply to the home in the event of an earthquake, helping to prevent gas-related disasters such as explosions or fires.
Excess flow valves, on the other hand, are designed to detect a sudden increase in the flow of gas, which may be an indication of a gas leak. These valves are typically installed on the gas line leading to individual appliances, such as a water heater or furnace. If a gas line is damaged, or a fitting becomes loose, the valve will sense the increased flow of gas and shut off the gas supply to that particular appliance. This can help prevent a gas leak from causing an explosion or fire in the home.
Excess flow valves are particularly useful for detecting gas leaks that occur after the main gas shut off valve, such as in a specific appliance or gas line. They can also be used in conjunction with seismic valves to provide an additional layer of protection against gas leaks. Because we live in an area with high seismic activity, a seismic valve is what most homeowners install to protect their home in case of seismic activity.
The process of installing a seismic valve is similar to that of a standard automatic gas shut off valve, with a few additional considerations due to its earthquake-sensitive design. Before installing a seismic valve, it is important to consult with a licensed professional to ensure that the valve is appropriate for your location and to determine the best placement for the valve. The gas supply to the home must be turned off before installing the valve. The seismic valve should be installed on the interior side of the gas meter, in a location that is easily accessible, and securely fastened to the wall to prevent it from falling during an earthquake.
The valve should be connected to the gas line using a flexible connector to allow for movement during an earthquake. It is important to ensure that the gas line is properly sized and that all connections are tight to prevent gas leaks. Once the valve is installed, it should be tested to ensure that it is working properly. This can be done by simulating an earthquake, such as by shaking the gas meter or using a vibration simulator. Once the valve has been installed and tested, the gas supply can be restored by turning on the main gas shut off valve.
Finally, it is important to have the installation inspected by a licensed professional to ensure that the valve is installed correctly and meets all safety standards. We recommend having the valve installed by a licensed professional. By working with a professional, you can ensure that your home is equipped with a seismic valve that is installed correctly and that will provide the protection you need in the event of an earthquake.
You can see the installation process for a seismic gas valve here: