Lennox Main Boards

123 products

wishlist

Image
Product
Price
Quantity
Options
Action

Welcome to the South Mini Splits collection for Lennox Main Boards. As the "brain" of your HVAC system, these boards manage the primary logic, timing, and safety protocols required for peak performance. We provide high-quality, authentic replacement components and sophisticated control subassemblies to keep your inverter-driven systems running efficiently.

Our extensive inventory ensures compatibility across various Lennox Main Boards platforms. Whether you need the Duct MCB V2 (17123000011299) for indoor ducted units or a specialized Electronic Control Box Subassembly (17222000037708) for advanced DC inverter technology, we have the precision-engineered parts necessary for routine repairs or complex system overhauls.

💡 Why Choose South Mini Splits for Your Lennox Main Boards?

  • ✅Wholesale Pricing: Competitive rates on critical electronic components and subassemblies.
  • ✅USA-Based Support: Expert technical assistance to help you identify the exact board for your specific model number, such as the Main Control Board Subassembly (17122000018658).
  • ✅Free Shipping Over $300: Get your vital replacement parts delivered fast to minimize system downtime.

Understanding Lennox Main Boards Control Ecosystems

Modern inverter systems utilize a complex ecosystem of boards working in tandem:

Technical Facts & Performance Advantages

Mini Split BTU Sizing & Application Guide

Use our quick reference chart to match your room size with the ideal system capacity.

Capacity Sq. Footage Application
6,000 BTU150–250Small bedrooms & offices
9,000 BTU250–450Standard bedrooms
12,000 BTU450–600Kitchens & studios
18,000 BTU600–1,000Living rooms & garages
24,000 BTU1,000–1,200Open floor plans
36,000 BTU1,500–1,700Commercial & fitness
48,000 BTU1,900–2,100Large warehouses
60,000 BTU2,400–2,800+Commercial estates

When to "Size Up"

High Ceilings (10ft+)

If your ceilings are 10 feet or higher, you are cooling a larger volume of air. We recommend increasing your BTU choice by 20%.

Poor Insulation

For older homes or buildings with single-pane windows, opt for the next size up to ensure the unit can maintain the set temperature.

Kitchen Environments

Appliances generate significant heat. If the unit is for a kitchen, add 4,000 BTUs to your square footage calculation.

Heavy Sun Exposure

Rooms with large south-facing windows or "sunrooms" act like greenhouses. Increase your BTU capacity by 10-15%

Occupancy

If the area regularly hosts more than two people (like a conference room or classroom), add 600 BTUs per additional person..

Need Help Sizing?

If you aren't sure which unit is right for your project, use our BTU Calculator or contact our USA-based support team for a custom recommendation.

Open BTU Calculator

Frequently Asked Questions

A: If your outdoor condenser connects to only one indoor unit, use a board like the Main Control Board Sub-Single Only (17123000008577). Multi-zone systems require boards designed to manage complex communication between zones.

A: No. Control boards are programmed with specific firmware for different BTU capacities. A 12k BTU unit board like the Main Control Board (30138000318) has different logic than a 24k BTU unit board like the Main Control Board (30138000192).

A: "Subassemblies" usually consist of just the board, while "Assemblies" or "Electric Boxes", like the Electronic Control Box Assembly (17222000033256), often include the protective housing.

A: It depends on the part number. Some items are "Subassemblies" (just the board), while others, like the Electric Box Assy (10000100013), include the protective metal or plastic housing.

A: A V2, such as the Duct MCB V2 (17123000011303), is typically an updated version. Always check communication protocols or contact our support to verify backwards compatibility.