CPSC campaign 24161
Hazard
The blocked vent switch (BVS) can fail to shut down the burners if the boilers are installed at altitudes above 5,400 feet and the vent system becomes blocked. In such an event, the boiler can emit excessive amounts of carbon monoxide into the home, posing a carbon monoxide (CO) poisoning hazard to consumers.
Remedy
Consumers with the recalled boilers should immediately contact U.S. Boiler to receive a free repair that includes a free replacement main burner gas orifice and a free replacement blocked vent switch if needed. Consumers who continue use of the boilers while awaiting repair should have working carbon monoxide alarms outside of sleeping areas and on each floor of the home.
The text above is quoted verbatim from the CPSC record. Confirm the affected units and the remedy with the manufacturer or CPSC. Recall data may be incomplete, delayed, or superseded.