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Mini-Split Heat Pump Product

Overview

A mini-split heat pump heats and cools a single room without ductwork. It splits into two boxes: a slim Indoor Unit mounted high on a wall and a Outdoor Unit sitting on the ground or a bracket outside. A thin refrigerant Refrigerant Line Set and a control wire are all that pass between them, so installation needs only a small hole through the wall. The same machine cools in summer and heats in winter by reversing the direction it moves heat, which is what makes a heat pump far more efficient than resistance heating.

The indoor head pulls room air through the Evaporator Coil with a quiet Cross-Flow Blower, steers the discharge with motorized louvers, and answers an IR Remote Control. Outside, the Inverter Rotary Compressor and Condenser Coil do the thermodynamic work, the Reversing Valve flips between heating and cooling, and the Inverter Drive Board sets the compressor speed.

How it works

Cooling and heating are the same vapor-compression cycle run in opposite directions. In cooling, the Inverter Rotary Compressor pressurizes refrigerant, the outdoor coil rejects heat, the refrigerant expands, and the indoor Evaporator Coil absorbs heat from the room. The Reversing Valve is a four-way valve that swaps the roles of the two coils on command, so in heating the outdoor coil gathers heat even from cold air and the indoor coil releases it into the room.

What sets a modern mini-split apart is the Inverter Drive Board. Instead of switching a fixed-speed compressor fully on and off, it rectifies mains power and synthesizes a variable-frequency drive for the compressor motor, using IGBT power switches under microcontroller control. The Inverter Rotary Compressor then runs slow and steady at part load and ramps up only when demand is high. This continuous modulation holds temperature within a fraction of a degree, eliminates the noisy start-stop cycling of older units, and is the main reason inverter mini-splits reach such high efficiency ratings.

Comfort and quiet come from the indoor side. The Cross-Flow Blower is a long cross-flow fan that moves a wide, gentle stream of air at low noise, and the Louver Stepper Motor steppers aim that air up or down. The unit talks to a handheld IR Remote Control, while the indoor and outdoor control boards coordinate over the interconnect wire. The whole circuit is charged with low-GWP R32 held in the outdoor unit and released into the Refrigerant Line Set when the service valves are opened at commissioning.

Build & assembly graph

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Bill of materials

6 top-level lines · 64 rows shown · 286 parts total · indented to 3 levels
# Item / sub-assembly Part no. Qty/assy Ext. qty Parts Type
1 Indoor Unit 7 parts minisplit-indoor-unit 1 134 assembly
1.1 Indoor Case & Front Cover minisplit-indoor-case 1 part
1.2 Evaporator Coil 3 parts minisplit-evaporator 1 4 assembly
1.2.1 Copper Coil Tube minisplit-copper-tube 1 part
1.2.2 Aluminum Fin Stack minisplit-aluminum-fin 1 part
1.2.3 Coil Header minisplit-coil-header 2 part
1.3 Cross-Flow Blower 3 parts minisplit-indoor-blower 1 4 assembly
1.3.1 Blower Motor blower-motor 1 part
1.3.2 Cross-Flow Fan Barrel minisplit-cross-flow-barrel 1 part
1.3.3 Ball Bearing ball-bearing 2 part
1.4 Louver Stepper Motor 3 parts minisplit-louver-motor 2 23 assembly
1.4.1 Stator Assembly 3 parts + deeper › stator-assembly 2 3 assembly
1.4.2 Rotor Assembly 4 parts + deeper › rotor-assembly 2 19 assembly
1.4.3 Motor Housing motor-housing 2 part
1.5 Washable Air Filter minisplit-indoor-filter 1 part
1.6 Indoor Control PCB 5 parts minisplit-indoor-control 1 77 assembly
1.6.1 Bare PCB pcb-bare 1 part
1.6.2 Microcontroller mcu 1 part
1.6.3 SMD Passive (R/C/L) smd-passives 70× 70 part
1.6.4 Relay relay 1 part
1.6.5 Connector connector 4 part
1.7 Condensate Drain Hose minisplit-indoor-drain 1 part
2 Outdoor Unit 7 parts minisplit-outdoor-unit 1 40 assembly
2.1 Outdoor Case minisplit-outdoor-case 1 part
2.2 Inverter Rotary Compressor 6 parts minisplit-compressor 1 26 assembly
2.2.1 Stator Assembly 3 parts + deeper › stator-assembly 1 3 assembly
2.2.2 Rotor Assembly 4 parts + deeper › rotor-assembly 1 19 assembly
2.2.3 Copper Winding copper-winding 1 part
2.2.4 Motor Housing motor-housing 1 part
2.2.5 Rolling Piston minisplit-rolling-piston 1 part
2.2.6 Refrigeration Oil minisplit-compressor-oil 1 part
2.3 Condenser Coil 3 parts minisplit-condenser 1 4 assembly
2.3.1 Copper Coil Tube minisplit-copper-tube 1 part
2.3.2 Aluminum Fin Stack minisplit-aluminum-fin 1 part
2.3.3 Coil Header minisplit-coil-header 2 part
2.4 Outdoor Axial Fan 3 parts minisplit-outdoor-fan 1 3 assembly
2.4.1 Blower Motor blower-motor 1 part
2.4.2 Axial Fan Blade minisplit-axial-blade 1 part
2.4.3 Fan Guard minisplit-fan-guard 1 part
2.5 Reversing Valve 3 parts minisplit-reversing-valve 1 3 assembly
2.5.1 Four-Way Valve Body minisplit-four-way-body 1 part
2.5.2 Solenoid Coil minisplit-solenoid-coil 1 part
2.5.3 Relay relay 1 part
2.6 Service Valve minisplit-service-valve 2 part
2.7 R32 Refrigerant Charge minisplit-refrigerant-charge 1 part
3 Inverter Drive Board 7 parts minisplit-inverter-board 1 97 assembly
3.1 Bare PCB pcb-bare 1 part
3.2 Microcontroller mcu 1 part
3.3 IGBT Power Module minisplit-igbt-module 1 part
3.4 Bridge Rectifier minisplit-rectifier 1 part
3.5 DC-Bus Capacitor minisplit-dc-cap 2 part
3.6 Power Heatsink minisplit-heatsink 1 part
3.7 SMD Passive (R/C/L) smd-passives 90× 90 part
4 Refrigerant Line Set 4 parts minisplit-line-set 1 7 assembly
4.1 Liquid Line minisplit-liquid-line 1 part
4.2 Suction Line minisplit-suction-line 1 part
4.3 Line Insulation minisplit-line-insulation 1 part
4.4 Flare Nut minisplit-flare-nut 4 part
5 IR Remote Control 4 parts minisplit-remote 1 4 assembly
5.1 Bare PCB pcb-bare 1 part
5.2 Microcontroller mcu 1 part
5.3 LCD Panel lcd-panel 1 part
5.4 Remote Keypad minisplit-remote-keypad 1 part
6 Connector connector 4 part

Sourcing — likely vendors

Companies that make this · indicative price $100–$20k · MOQ & lead are typical
VendorHQSpecialtyMOQLead time
🇺🇸Carrier
carrier.com ↗
Palm Beach Gardens, US HVAC 500 units 8–14 wks
tranetechnologies.com ↗ Davidson, US HVAC 500 units 8–14 wks
🇯🇵Daikin
daikin.com ↗
Osaka, JP HVAC 500 units 8–14 wks
🇺🇸Lennox
lennox.com ↗
Richardson, US HVAC 500 units 8–14 wks
johnsoncontrols.com ↗ Milwaukee, US Building systems 500 units 8–14 wks

421-word article