The Lennox 33W18 (101599-02) 2-Stage Pressure Switch is a reliable safety component engineered to ensure accurate monitoring of airflow and combustion pressure in residential and commercial HVAC systems. Designed for use in two-stage furnaces and air handlers, this pressure switch provides dependable operation with a high set point of 1.32 inches water column (W.C.) and a low set point of 0.20 inches W.C., making it suitable for multi-stage applications requiring precise pressure differentiation.

Manufactured to Lennox’s strict quality standards, this pressure switch helps protect the system by verifying proper venting and draft conditions before allowing the ignition sequence to proceed. The 2-stage design supports systems that require different pressure thresholds for first and second stage operation, improving performance and efficiency. Installation is straightforward for qualified service technicians, and the durable construction ensures long-lasting functionality even under demanding operating conditions.

This pressure switch is an ideal replacement part for maintaining optimal performance and safety in compatible Lennox heating equipment. It ensures consistent pressure monitoring to help prevent inefficient operation or potential system faults caused by improper draft conditions.

 

Key Specifications:

• OEM Part Number: 33W18 / 101599-02
• Type: 2-Stage Pressure Switch
• High Set Point: 1.32" W.C.
• Low Set Point: 0.20" W.C.
• Application: Two-stage HVAC systems requiring dual pressure thresholds
• Quality: Genuine Lennox replacement component