High Gas Pressure Incident in Merrimack Valley

The high gas pressure incident that took place north of Boston on September 13, 2018 was an unprecedented failure in the regulation of gas pressure in the Columbia Gas distribution system. It is reported that as many as 80 homes and buildings were damaged or destroyed with a total of about 8,600 of their customers affected. While the full scope of the failure is still under investigation, the federal Pipeline and Hazardous Materials Safety Administration (PHMSA) has reported that the gas pressure in the affected area was 12 times higher than the system was intended to operate at.

Viessmann gas-fired boilers are certified by the Canadian Standards Association (CSA) in accordance with ANSI standard Z21.13 to operate at a maximum of 14 inches of water column (0.5 PSI). Exposure to gas pressures above the maximum rating can cause significant damage to the gas valve, burner assembly, internal gas delivery tubing and vent system. Often, the damage is undetectable with visual inspection. Operating the boiler after being exposed to high gas pressure is potentially hazardous and is not recommended.

Viessmann recommends that homeowners or owners of potentially affected gas boilers contact Columbia Gas to determine if their building experienced gas pressure higher than 14 inches of water column. Because we don't know the level to which this pressure may have been exceeded due to this incident, Viessmann recommends that the complete boiler including the burner and controls be replaced and a qualified and licensed professional inspect and verify the integrity of the gas line, venting system and intake system for additional damage.

Viessmann Technical Support professionals are available to answer any additional questions. The technical support number is 1-888-484-8643.