Fema VNM111-513 pressure switch

Fema VNM111-513 pressure switch, listed as catalogue article 444.676.020 and manufacturer code VNM111-513. This is a pressure switch from the Fema brand, classified under the catalogue category of pressure switches. Parts of this type serve as safety devices that verify whether pressure or airflow in a burner system is within the permitted operating range. The burner control relies on this signal to continue the ignition sequence; without a confirmed pressure signal, the control locks out. In air applications, the switch proves the fan is moving air; in gas applications, it guards minimum or maximum gas pressure. When replacing a pressure switch of this general class, the medium (air or gas), switching range and differential, connection type (thread or hose spigot), contact rating, and approval class must match the original specification. Common failure modes include a torn diaphragm, a blocked impulse tube, or a drifted setpoint—all of which can cause lockouts that may be misdiagnosed as ignition problems. No further specifications or compatibility details for this specific article are provided in the source data.