but matching the SKU is the most reliable method

Technical Reliability: Features industry-standard terminals for secure HVAC relay wiring and long-term durability in the field

OEM Compatibility: Specifically engineered for a drop-in fit for QMark

it refers to the switch contacts closing when the negative pressure (vacuum) reaches the 1

Schneider Electric (Barber Colman) TC-1101-500 Thermostat R-410A but matching the SKU isEnsure precise climate control on your next service call with the Schneider Electric Barber Colman TC 1101 500. This bimetal, two position electric room thermostat is a standard tier solution for applications requiring on off control of fan coils, motor starters, contactors, and two position electric actuators. Designed for high reliability switching, this unit features a SPDT snap action switch that supports both low and line voltage (24 to 277 VAC)