Description
The Lennox 13R28 Low Pressure Switch detects a drop in refrigerant pressure within the low-side circuit and opens the electrical contact when system pressure falls below the 90-PSI threshold, signaling the control board to shut down compressor operation in HVAC systems. A pressure-sensitive diaphragm element responds to suction line pressure changes by breaking the circuit at the preset cutout point, protecting the compressor from running under low charge or restricted airflow conditions. Fitted along the suction line of split-system and packaged air conditioning units, it threads directly into the access port.
