Lennox 49L92 Pressure Switch

The Lennox 49L92 Pressure Switch is a high-precision OEM HVAC replacement part engineered for critical safety monitoring in Lennox gas furnaces and air handlers. This 0.58" WC SPST pressure switch is a normally open (N.O.) control that verifies the inducer motor is generating the correct negative pressure to vent combustion gases safely. As the direct equivalent to part numbers 49L9201 and LB-109531B, this component ensures your system meets factory-spec airflow requirements before allowing the ignition sequence to proceed.

Constructed with a dual 1/4" barb connection for secure pneumatic tubing attachment, the 49L92 is built to withstand high-temperature environments typical of modern condensing units. This single-pole single-throw (SPST) safety switch is compatible with a wide range of Lennox equipment, including G40UH series furnaces and 80% to 90% AFUE units. For technicians, using genuine Lennox parts like this pressure switch is essential for maintaining equipment integrity and ensuring accurate differential pressure sensing without the "nuisance trips" often associated with generic alternatives.

Key Benefits

• Universal System Integrity: As a Lennox genuine OEM part, it guarantees precise 0.58" WC calibration for consistent safety circuit operation.
• Direct Compatibility: Replaces 49L9201 and fits popular residential models like the Lennox G40UH-48C-110-11.
• Rugged Design: Features a durable housing and dual 1/4" barb hose connections to prevent vacuum leaks and ensure a stable connection to the inducer housing or collector box.
• Optimized Safety: Prevent the hazardous buildup of flue gases by ensuring the furnace draft inducer is performing at its designated RPM.

Common Questions

Is the Lennox 49L92 identical to the 49L9201?
Yes, the 49L92 and 49L9201 are the same Lennox pressure switch; the additional suffix is often used in manufacturer inventory systems but refers to the same 0.58" WC component.

What are the symptoms of a failing 0.58" WC pressure switch?
Common signs include the furnace failing to ignite while the inducer motor runs, or Lennox diagnostic codes indicating a pressure switch stuck open or closed during the pre-purge cycle.

Can I use this switch on Armstrong or Ducane furnaces?
Yes, because Lennox belongs to the same parent company, this 49L92 pressure switch is frequently used as a factory replacement part for select Armstrong and Ducane HVAC units. Always verify the WC rating on the existing switch before installation.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.