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Lennox

OEM Lennox Integrated Modular DDC Controller — 86M39

SKU: LNX-86M39 Brand: Lennox
$39.95 $54.95

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Texas CMBL #19328542014
SAM.gov Registered
Govt POs Accepted

The genuine OEM Lennox 86M39 is an Integrated Modular Controller (IMC) functioning as the DDC controller and interface for Lennox commercial rooftop and packaged units. This board orchestrates the unit's digital direct control logic — sequencing heating, cooling, economizer, and blower operation while providing the communication interface between your Lennox equipment and the building automation system for centralized management.

Common failure symptoms: When the 86M39 controller fails, the unit may ignore thermostat or BAS commands, stage erratically, display fault or communication error codes, lose economizer and damper control, or fail to power on. Blank displays, lost network connectivity, and unresponsive control inputs or outputs commonly point to a defective board.

Why OEM matters: The Lennox integrated modular controller is engineered and pre-configured for Lennox unit architecture. Installing the factory 86M39 ensures the correct firmware, terminal assignments, and reliable integration with your existing Lennox controls. Aftermarket or improperly configured boards invite mismatches and unreliable performance — always choose the genuine OEM part.

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

Frequently Asked Questions

Does this Control Board fit my Lennox OEM Lennox Integrated Modular DDC Controller — 86M39?
Yes. This is the factory-specified OEM control board for the Lennox OEM Lennox Integrated Modular DDC Controller — 86M39. It is a direct drop-in replacement that fits without modification. Always verify the model number on your equipment nameplate before ordering.
How do I replace the control board on my Lennox OEM Lennox Integrated Modular DDC Controller — 86M39?
Difficulty: Advanced (1–2 hrs)
Step 1: Turn off breaker. Step 2: PHOTOGRAPH all wire connections before touching anything. Step 3: Label each wire with tape. Step 4: Disconnect all wires, remove old board. Step 5: Mount new board, reconnect all wires matching your photo exactly. Step 6: Restore power and test all modes. Exact part number match is critical.
My HVAC system is completely dead. What could be wrong?
Completely dead HVAC (no LED on board) = failed control board or blown fuse. Check board fuse first (3A or 5A, costs $1–$5). If fuse is good and board has power but no LED, board is dead. Always photograph wiring before replacing.
Is this control board compatible with Bryant or Payne too?
Many Lennox parts are cross-compatible with Bryant and Payne since all three brands are manufactured by Carrier Global Corporation. The same physical part is often used across brand labels with different model numbers. To verify: check your Bryant or Payne equipment service manual for cross-compatible part numbers, or email info@nationalhvacparts.com with your model number.
Should I use OEM or aftermarket for my Lennox control board?
OEM essential. Control boards are model-specific with precise firmware and connector layouts. Aftermarket boards rarely match all functions and can cause intermittent failures or safety issues. Always match the exact OEM part number.
How fast does National HVAC Parts ship?
Orders placed before 3:00 PM CST ship the same business day. Standard delivery is 2–5 business days anywhere in the continental United States. Express shipping available at checkout. We ship from Houston, TX to all 50 states. 30-day return policy on all parts.
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Mike Rivera
HVAC Parts Specialist — Online