Description
The Lennox 51W90 is a single pole-single throw pressure switch used to measure pressure in your Lennox HVAC system. In the switch functions like a safety switch that breaks an electrical circuit when the air pressure is less than set point of 0.65″ W.C. This assists in protecting your equipment from destruction by low air pressure situations. For example, pressure could be low, this could point out that the system’s filter is blocked or that there is a leak somewhere in the duct work, this would lead to the car overheating and possible component failure.









