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Excess flow valves

An excess flow valve (EFV) is an underground device that automatically restricts the flow of natural gas if there is a sudden break in the service line. PSE began installing this device in 2006 with new or replaced services to single family residences and expanded the practice to include small multi-family and commercial service lines in 2013 when possible. As of April 14, 2017, certain residential and small commercial customers who don’t have an excess flow valve may request to have one installed by PSE at the customer’s expense.

How does an EFV work?

An EFV is usually located near where the gas service joins the gas main (e.g., close to the street or near the property line). If the service pipe downstream of this valve is severed, the sudden increase in the flow of gas may trigger the valve and reduce the flow of gas under certain conditions. It will not protect against a malfunctioning appliance, a leak on any of the pipelines on the customer’s side of the meter, a meter leak, or small punctures in the service line. An EFV may not protect against damage to a service line from earthquakes or flooding.

How to request an installation

Most residential and small commercial customers can have an EFV installed if the site meets the installation requirements. Customers who wish to have an EFV installed should contact us at
1-888-321-7779 to arrange installation at a mutually agreed upon date.

Please note:

  1. An EFV may not be feasible for some customers due to design constraints; for example, where gas pressure is too low to trigger the valve.
  2. The installation may only be performed by PSE or one of our approved service providers.
  3. The cost of installing the EFV depends on the particulars of the job. Costs will typically not be lower than $1,500 and could be significantly higher if the installation requires restoration of paved or concrete surfaces. You will be billed for the estimated costs associated with the installation.

Call 811 before digging

EFVs are best suited to protect against breaks caused by excavation. However, the surest way to avoid breaking a gas line during excavation is to call 811 two business days before digging. PSE will mark the locations of our gas and electric lines at no cost to you so that you or your contractor can dig safely to avoid them.