Lennox M22A018S4-2P

INSTALLATION
INSTRUCTIONS
©
2016 Lennox Industries Inc.
Dallas, Texas, USA
MLA/MPA/MPB and
M22A/M33A/M33B Series
SINGLE-ZONE MINI-SPLIT SYSTEMS
(208/230V) --
Cassette-Mounted Indoor Unit
507546-06
10/2017
Supersedes 10/2016
WARNING
Improper installation, adjustment, alteration, ser vice or
maintenance can cause property damage, personal
injury or loss of life.
Installation and service must be performed by a li censed
professional HVAC installer (or equivalent) or a service
agency.
WARNING
The clean Air Act of 1990 bans the intentional venting of
refrigerant (CFCs, HCFCs, and HFCs) as of July, 1992.
Approved methods of recovery, recycling or reclaiming
must be followed. Fines and/or incarceration may be
levied for non-compliance.
WARNING
This product contains a chemical known to the State
of California to cause cancer, birth defects, or other
reproductive harm.
CAUTION
As with any mechanical equipment, contact with sharp
sheet metal edges can result in personal injury. Take
care while handling this equipment and wear gloves and
protective clothing.
General
Refer to the Product Specications bulletin (EHB) for more
product information.
These instructions are intended as a general guide and
do not supersede local or national codes in any way.
Authorities having jurisdiction should be consulted before
installation.
The M22A, M33A and M33B ceiling cassette indoor units
are matched with an outdoor heat pump unit to create a
mini-split system that uses HFC-410A refrigerant.
Table of Contents
General ...........................................................................1
Included Parts.................................................................2
Model Number Identication ...........................................3
Indoor / Outdoor Unit Match-Ups....................................4
Typical System Components ..........................................5
System Dimensions ........................................................6
Outdoor Units................................................................6
Indoor Units ..................................................................7
System Clearances ........................................................9
Outdoor Unit .................................................................9
Indoor Unit ....................................................................9
Torque Requirements for Caps and Fasteners.............10
Indoor Unit Installation ..................................................10
Unit Placement Considerations ..................................10
Installation of Cassette Base ......................................10
Installation of M33 Cassette Cover Panel...................11
Indoor Unit Condensate Piping Connections ..............13
Outdoor Unit Installation ...............................................13
Placement Considerations ..........................................13
Direct Sunlight, Rain, Snow and Ice Protection ..........14
Prevailing Winds .........................................................15
Buried Refrigerant Pipe Protection .............................15
Outdoor Unit Condensate Piping ................................15
Securing the Outdoor Unit ..........................................16
Refrigerant Piping Connections ....................................17
Leak Test and Evacuation ............................................18
Leak Test ....................................................................18
Triple Evacuation Procedure .......................................18
Wiring Connections ......................................................19
Outdoor Unit ..............................................................19
Indoor Unit ..................................................................19
Unit Start-Up .................................................................27
Adding Refrigerant for Longer Line Set ........................27
Troubleshooting ............................................................28
Test Run .......................................................................28
Pre-Checks .................................................................28
Procedure ...................................................................28
Dry Mode Operation (Dehumidication) .......................28
Procedure ...................................................................28
Sequence of Operation ...............................................28
THIS MANUAL MUST BE LEFT WITH THE OWNER
FOR FUTURE REFERENCE

Lennox M22A018S4-2P Specifications

General

Energy Efficiency Ratio (EER)	Up to 11.5
Phase	1
Refrigerant	R-410A
Cooling Capacity	18, 000 BTU/h
Voltage	208/230V
Tonnage	1.5 Tons

Summary

Installation Instructions

IndoorOutdoor Unit Match-Ups

Torque Requirements and Indoor Unit Installation

Installation of Cassette Cover Panel

Cover Panel Installation and Adjustment

Condensate Piping and Outdoor Unit Installation

Securing the Outdoor Unit

Refrigerant Piping Connections

Details the process of connecting refrigerant lines, including torque specifications.

Leak Test and Evacuation

Covers procedures for testing the system for leaks and evacuating refrigerant.

Wiring Connections

Provides guidelines for power and communication wiring for both units.

Single Zone Wiring Diagrams

Illustrates single-zone wiring configurations for the system.

Unit Wiring Diagrams

Presents wiring diagrams for various indoor and outdoor unit models.

Outdoor Unit Wiring Diagrams

Details wiring diagrams specific to different outdoor unit models.

Outdoor Unit Wiring Diagrams (Continued)

Unit Start-Up and Refrigerant Addition

Covers initial unit start-up procedures and refrigerant addition.

Troubleshooting and Operation