Lennox 57M66 Pressure Switch
The Lennox 57M66 Pressure Switch is a critical safety component designed for precise combustion air proving in high-efficiency gas furnaces. Factory-calibrated to actuate at 1.41" WC, this Single-Pole Single-Throw (SPST) switch ensures the inducer motor is generating sufficient static pressure to vent flue gases safely before allowing the ignition sequence to proceed. As a genuine OEM replacement part, it maintains the exact specifications required by Lennox, Armstrong, and Ducane heating systems, preventing unsafe operation due to blocked vents or inducer failure.
This furnace air pressure switch features dual 1/4" barb connections, allowing for accurate differential pressure monitoring across the heat exchanger. The rugged construction is engineered to withstand the thermal cycling typical of modern HVAC cabinets. Professionals frequently use the 57M6601 to resolve "pressure switch stuck open" codes (such as 2-flash or 3-flash Lennox codes), ensuring the system returns to peak performance without the reliability risks associated with universal alternatives.
Key Benefits
- Precise Actuation: Factory-set at 1.41 inches water column for reliable safety circuit closure.
- Dual-Port Versatility: The dual 1/4" barb connection supports both positive and negative pressure sensing.
- OEM Compatibility: Direct replacement for Lennox part 57M66 and 57M6601, as well as Honeywell IS22141081S5082.
- Safety Compliance: Verified to prove inducer operation and prevent ignition during flue obstructions or mechanical failures.
Common Questions
- What causes a Lennox 57M66 switch to stay open? Most issues stem from restricted venting, a failing inducer motor, or moisture/debris in the vacuum tubing. If the switch fails to close at 1.41" WC, the ignition sequence will be locked out for safety.
- Can I use a universal switch instead of this model? It is highly recommended to use the Lennox OEM pressure switch to ensure the exact setpoint matches the manufacturer's safety requirements for your specific furnace model.
- How do I verify the switch is bad? Technicians should use a manometer to measure the actual pressure produced by the inducer and a multimeter to check for continuity across the SPST contacts once the setpoint 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: $75.33
-65%$75.33
$26.37Lennox 57M66 Pressure Switch
The Lennox 57M66 Pressure Switch is a critical safety component designed for precise combustion air proving in high-efficiency gas furnaces. Factory-calibrated to actuate at 1.41" WC, this Single-Pole Single-Throw (SPST) switch ensures the inducer motor is generating sufficient static pressure to vent flue gases safely before allowing the ignition sequence to proceed. As a genuine OEM replacement part, it maintains the exact specifications required by Lennox, Armstrong, and Ducane heating systems, preventing unsafe operation due to blocked vents or inducer failure.
This furnace air pressure switch features dual 1/4" barb connections, allowing for accurate differential pressure monitoring across the heat exchanger. The rugged construction is engineered to withstand the thermal cycling typical of modern HVAC cabinets. Professionals frequently use the 57M6601 to resolve "pressure switch stuck open" codes (such as 2-flash or 3-flash Lennox codes), ensuring the system returns to peak performance without the reliability risks associated with universal alternatives.
Key Benefits
- Precise Actuation: Factory-set at 1.41 inches water column for reliable safety circuit closure.
- Dual-Port Versatility: The dual 1/4" barb connection supports both positive and negative pressure sensing.
- OEM Compatibility: Direct replacement for Lennox part 57M66 and 57M6601, as well as Honeywell IS22141081S5082.
- Safety Compliance: Verified to prove inducer operation and prevent ignition during flue obstructions or mechanical failures.
Common Questions
- What causes a Lennox 57M66 switch to stay open? Most issues stem from restricted venting, a failing inducer motor, or moisture/debris in the vacuum tubing. If the switch fails to close at 1.41" WC, the ignition sequence will be locked out for safety.
- Can I use a universal switch instead of this model? It is highly recommended to use the Lennox OEM pressure switch to ensure the exact setpoint matches the manufacturer's safety requirements for your specific furnace model.
- How do I verify the switch is bad? Technicians should use a manometer to measure the actual pressure produced by the inducer and a multimeter to check for continuity across the SPST contacts once the setpoint 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 57M66 Pressure Switch is a critical safety component designed for precise combustion air proving in high-efficiency gas furnaces. Factory-calibrated to actuate at 1.41" WC, this Single-Pole Single-Throw (SPST) switch ensures the inducer motor is generating sufficient static pressure to vent flue gases safely before allowing the ignition sequence to proceed. As a genuine OEM replacement part, it maintains the exact specifications required by Lennox, Armstrong, and Ducane heating systems, preventing unsafe operation due to blocked vents or inducer failure.
This furnace air pressure switch features dual 1/4" barb connections, allowing for accurate differential pressure monitoring across the heat exchanger. The rugged construction is engineered to withstand the thermal cycling typical of modern HVAC cabinets. Professionals frequently use the 57M6601 to resolve "pressure switch stuck open" codes (such as 2-flash or 3-flash Lennox codes), ensuring the system returns to peak performance without the reliability risks associated with universal alternatives.
Key Benefits
- Precise Actuation: Factory-set at 1.41 inches water column for reliable safety circuit closure.
- Dual-Port Versatility: The dual 1/4" barb connection supports both positive and negative pressure sensing.
- OEM Compatibility: Direct replacement for Lennox part 57M66 and 57M6601, as well as Honeywell IS22141081S5082.
- Safety Compliance: Verified to prove inducer operation and prevent ignition during flue obstructions or mechanical failures.
Common Questions
- What causes a Lennox 57M66 switch to stay open? Most issues stem from restricted venting, a failing inducer motor, or moisture/debris in the vacuum tubing. If the switch fails to close at 1.41" WC, the ignition sequence will be locked out for safety.
- Can I use a universal switch instead of this model? It is highly recommended to use the Lennox OEM pressure switch to ensure the exact setpoint matches the manufacturer's safety requirements for your specific furnace model.
- How do I verify the switch is bad? Technicians should use a manometer to measure the actual pressure produced by the inducer and a multimeter to check for continuity across the SPST contacts once the setpoint 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.
