Lennox 15P85 Pressure Switch
The Lennox 15P85 Pressure Switch is a critical safety component designed for precise combustion air pressure monitoring in HVAC systems. Specifically calibrated with a 0.55" WC set point (Water Column), this OEM replacement part (also identified by part number 105078-01 and 101859-07) ensures that the inducer motor is generating sufficient draft before allowing the ignition sequence to proceed. Engineered for reliability in Lennox gas furnaces, this SPST normally open switch actuates to close the circuit once the necessary negative pressure is achieved, effectively preventing the operation of the furnace under hazardous venting conditions such as flue blockages or inducer assembly failure.
Built with high-grade, heat-resistant materials, the 15P85 features a standard 5A resistive at 24VAC contact rating, making it a direct-fit solution for technicians servicing high-efficiency units. Its compact housing and clearly marked ports facilitate a streamlined pressure switch installation, maintaining the tight tolerances required for modern combustion air safety circuits. By accurately sensing the differential pressure between the collector box and the atmosphere, this component protects the heat exchanger and ensures optimal burner performance throughout the heating cycle.
Key Benefits:
- Precise 0.55" WC Calibration: Ensures the system only fires when proper venting air pressure and draft are established.
- Direct OEM Compatibility: Replaces Lennox 15P85 and 105078-01 without the need for field modifications or bracket adjustments.
- Robust Electrical Design: Features SPST-N.O. contacts rated for 24V furnace control circuits.
- Safety Compliance: Vital for preventing furnace error codes related to pressure switch stay-open or stay-closed faults (e.g., Error 227 or 229).
Common Questions:
- Why is my furnace giving a pressure switch open error? This usually indicates the inducer motor is not pulling enough vacuum, possibly due to a clogged vent pipe, a cracked pressure switch hose, or a failing draft inducer.
- Can I use a switch with a different WC rating? No. Using a switch with a lower or higher WC set point than the original .55" WC rating can lead to unsafe operation or frequent nuisance tripping.
- How do I test the Lennox 15P85? Use a manometer to verify the draft pressure and a multimeter to check for continuity across the terminals once the 0.55" WC threshold is reached.
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.
Original: $24.20
-65%$24.20
$8.47Lennox 15P85 Pressure Switch
The Lennox 15P85 Pressure Switch is a critical safety component designed for precise combustion air pressure monitoring in HVAC systems. Specifically calibrated with a 0.55" WC set point (Water Column), this OEM replacement part (also identified by part number 105078-01 and 101859-07) ensures that the inducer motor is generating sufficient draft before allowing the ignition sequence to proceed. Engineered for reliability in Lennox gas furnaces, this SPST normally open switch actuates to close the circuit once the necessary negative pressure is achieved, effectively preventing the operation of the furnace under hazardous venting conditions such as flue blockages or inducer assembly failure.
Built with high-grade, heat-resistant materials, the 15P85 features a standard 5A resistive at 24VAC contact rating, making it a direct-fit solution for technicians servicing high-efficiency units. Its compact housing and clearly marked ports facilitate a streamlined pressure switch installation, maintaining the tight tolerances required for modern combustion air safety circuits. By accurately sensing the differential pressure between the collector box and the atmosphere, this component protects the heat exchanger and ensures optimal burner performance throughout the heating cycle.
Key Benefits:
- Precise 0.55" WC Calibration: Ensures the system only fires when proper venting air pressure and draft are established.
- Direct OEM Compatibility: Replaces Lennox 15P85 and 105078-01 without the need for field modifications or bracket adjustments.
- Robust Electrical Design: Features SPST-N.O. contacts rated for 24V furnace control circuits.
- Safety Compliance: Vital for preventing furnace error codes related to pressure switch stay-open or stay-closed faults (e.g., Error 227 or 229).
Common Questions:
- Why is my furnace giving a pressure switch open error? This usually indicates the inducer motor is not pulling enough vacuum, possibly due to a clogged vent pipe, a cracked pressure switch hose, or a failing draft inducer.
- Can I use a switch with a different WC rating? No. Using a switch with a lower or higher WC set point than the original .55" WC rating can lead to unsafe operation or frequent nuisance tripping.
- How do I test the Lennox 15P85? Use a manometer to verify the draft pressure and a multimeter to check for continuity across the terminals once the 0.55" WC threshold is reached.
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.
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Description
The Lennox 15P85 Pressure Switch is a critical safety component designed for precise combustion air pressure monitoring in HVAC systems. Specifically calibrated with a 0.55" WC set point (Water Column), this OEM replacement part (also identified by part number 105078-01 and 101859-07) ensures that the inducer motor is generating sufficient draft before allowing the ignition sequence to proceed. Engineered for reliability in Lennox gas furnaces, this SPST normally open switch actuates to close the circuit once the necessary negative pressure is achieved, effectively preventing the operation of the furnace under hazardous venting conditions such as flue blockages or inducer assembly failure.
Built with high-grade, heat-resistant materials, the 15P85 features a standard 5A resistive at 24VAC contact rating, making it a direct-fit solution for technicians servicing high-efficiency units. Its compact housing and clearly marked ports facilitate a streamlined pressure switch installation, maintaining the tight tolerances required for modern combustion air safety circuits. By accurately sensing the differential pressure between the collector box and the atmosphere, this component protects the heat exchanger and ensures optimal burner performance throughout the heating cycle.
Key Benefits:
- Precise 0.55" WC Calibration: Ensures the system only fires when proper venting air pressure and draft are established.
- Direct OEM Compatibility: Replaces Lennox 15P85 and 105078-01 without the need for field modifications or bracket adjustments.
- Robust Electrical Design: Features SPST-N.O. contacts rated for 24V furnace control circuits.
- Safety Compliance: Vital for preventing furnace error codes related to pressure switch stay-open or stay-closed faults (e.g., Error 227 or 229).
Common Questions:
- Why is my furnace giving a pressure switch open error? This usually indicates the inducer motor is not pulling enough vacuum, possibly due to a clogged vent pipe, a cracked pressure switch hose, or a failing draft inducer.
- Can I use a switch with a different WC rating? No. Using a switch with a lower or higher WC set point than the original .55" WC rating can lead to unsafe operation or frequent nuisance tripping.
- How do I test the Lennox 15P85? Use a manometer to verify the draft pressure and a multimeter to check for continuity across the terminals once the 0.55" WC threshold is reached.
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.
