Winter Gas Delivery Hazards

As the US continues to experience winter’s cold grip, it’s important to understand warning signs that you should look for and actions to keep the natural gas flowing through the meter and into your home and business appliances. Gas service technicians should also be aware of these potential indicators of problems and corrective actions.

As snow and rain fall during freezing weather, they can cover your gas meter, including the regulator vent, with a dangerous precipitation layer. This can seal the vent, preventing air from freely moving in and out of the vent. This can cause the gas regulator to become inoperable, which is a potentially hazardous situation.

If you don’t know the significance of the gas regulator at your house, you’re not alone. The gas regulator is installed as part of the gas meter piping, usually upstream or before the gas meter. The regulator is not a very exciting component. It sits in the same place for years and, from its exterior, appears to be not moving or performing any critical function. However, the gas regulator is the most critical component of a customer’s gas delivery system. The regulator must function properly to ensure the safe delivery of natural gas. ??

For a typical gas regulator to operate properly, the regulator’s diaphragm is subjected to constant force applied to one side by an adjustable spring. Then, the other side moves back and forth as the gas pressure and flow push against it due to changes in the downstream gas system. This diaphragm movement allows the regulator valve to move away from the regulator seat when increased downstream gas flow is needed and for the valve to close and seal tightly against the regulator’s seat during periods of low or no downstream gas flow.

In the diagram below, you can see the spring, diaphragm, valve, and rubber seat.

Potential Hazards

When a regulator vent becomes blocked, three potential hazards exist.

1. The vent may not operate, potentially leading to over or under-pressurizing downstream piping.
2. The regulator’s internal relief valve may not function due to the blocked vent screen, potentially leading to over or under-pressurization.
3. The regulator’s body may become damaged or break in two due to the weight of snow and ice load. ?

Prevention

The best prevention begins long before winter. During the other three seasons, look at your gas meter setting and determine if rainwater is spilling out of your home’s gutters due to clogging or damage, and take some time to fix the guttering. If you don’t have rain gutters, install them or find a way to divert the water flow from your home’s roof away from the gas meter setting.

In the photo below, a roof-like structure was constructed to protect the gas meter setting from rain, snow, and ice. Obviously, this is not ideal since the weight of the ice load on the roof structure is considerable, but at least that weight is not being applied to the gas meter setting, and the regulator vent is unobstructed.

Remediation

Once winter arrives, use the following to minimize Old Man Winter’s efforts to disrupt your home’s natural gas supply. ?

In addition to keeping your gas meter and regulator free of ice and snow, check other vents, such as intake and exhaust vents, for high-efficiency appliances such as furnaces and tankless water heaters. These vents often appear as an open white PVC (polyvinyl chloride) pipe extending through the building's wall to the exterior. They may also appear as a box with vent openings.

Dryer vents must be free of obstruction to operate, as well. If any of these vents become blocked, your appliances may not work properly or at all.

If you need help educating your workforce about proper venting of gas appliances, EWN has cutting-edge training for that. Contact us anytime.

Our Minnesota Department of Public Safety friends have a great blog post on this subject. Check it out here: https://dps.mn.gov/blog/Pages/20200206-clear-gas-meter-ice-snow.aspx

Stay warm! Stay safe! Keep those vents clear!