OEM Lennox Defrost Control Board R47181-001 — 46K67
OEM Guaranteed
Same-Day Ship
30-Day Returns
Secure Checkout
The genuine OEM Lennox 46K67 (factory number R47181-001) is a defrost control board for Lennox heat pump systems. It coordinates the defrost thermostat input with an internal timer to decide when the outdoor coil requires defrosting, then switches the reversing valve and outdoor fan to melt accumulated frost and keep the heat pump delivering efficient heat.
Common failure symptoms: When the 46K67 fails, the outdoor coil may build up heavy ice with no defrost, defrost may run continuously, the outdoor fan may behave erratically, or the system may lose heating capacity and lean on backup electric heat. Corroded relays, a cracked board, or no response from the diagnostic LED point to a failed control.
Why OEM matters: This board's timing and relay logic are calibrated specifically for Lennox reversing-valve and coil configurations. Substitute boards with mismatched timing or wiring can trigger nuisance defrosts, valve slugging, or compressor stress. Installing the factory 46K67 guarantees proper timing sequences, correct fit, and reliable defrost performance for your Lennox equipment.
Shipping Information
- Orders placed before 3PM CST ship same business day
- Standard delivery: 2-5 business days
- Express shipping available at checkout
- Free shipping on orders over $75
- Tracking number emailed upon shipment
Return Policy
- 30-day returns on unused parts in original packaging
- Electrical parts (capacitors, contactors, control boards) are final sale once installed
- Email info@nationalhvacparts.com to initiate a return
- Refunds processed within 5-7 business days