OEM Lennox Dual Pressure Switch Assembly w/ Bracket — 14T66
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The genuine OEM Lennox 14T66 is a dual pressure switch assembly complete with its mounting bracket. It verifies proper combustion airflow and venting by sensing the negative pressure created by the draft inducer before the furnace allows ignition. Both switches must confirm safe conditions, ensuring flue gases are being drawn away correctly and protecting your home from incomplete combustion.
Common failure symptoms: A faulty 14T66 often causes the furnace to lock out on ignition, produce a pressure-switch fault code, or fail to light entirely. You may hear the inducer motor start but no burner ignition follow. Stuck-open switches prevent operation, while stuck-closed switches defeat a vital safety check.
Why OEM matters: Pressure switches are calibrated to precise "inches of water column" set-points matched to your specific Lennox furnace and venting configuration. A generic replacement with the wrong rating can nuisance-trip or bypass essential safety limits. The factory 14T66 assembly arrives pre-set with the correct dual-switch calibration and bracket for a direct, worry-free installation.
Shipping Information
- Orders placed before 3PM CST ship same business day
- Standard delivery: 2-5 business days
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- 30-day returns on unused parts in original packaging
- Electrical parts (capacitors, contactors, control boards) are final sale once installed
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