Daikin-McQuay 349956813 Air Pressure Control High Limit Switch

The Daikin-McQuay 349956813 Pressure Control High Limit Air Pressure Switch is a control component used to detect air pressure that is too high and gives the signal to the control circuit when the limit is exceeded in HVAC systems. It operates on the concept of an internal diaphragm to change the airflow pressure and connect the high-limit switch contact when pressure surpasses the predetermined setting during the operation of air-handling and air-conditioning HVAC systems. It is attached to the air pressure sensing line, which has tubing connected to the pressure line and electrical connections made to the system.