ASCO TA20A31W Vacuum Deferential Combustion Switch

ASCO TA20A31W Vacuum Deferential Combustion Switch is a two‑piece ASCO S‑Series assembly that pairs a TA20A31W transducer with the SB31D switch module to monitor combustion vacuum differential. Designed for industrial combustion applications, it senses changes in vacuum within the burner or draft system and provides a switch output when the differential crosses the setpoint. The S‑Series arrangement consists of a separate transducer unit and switch unit, enabling modular configurations that can be field‑ or factory‑assembled to suit different installation needs. This exact TA20A31W/SB31D combination is part of ASCO’s legacy line of vacuum and differential switches used in combustion safety applications.