Lennox MWMA018S4-2P

INSTALLATION
INSTRUCTIONS
©
2017 Lennox Industries Inc.
Dallas, Texas, USA
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
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 MWMA and MWMB wall-mounted indoor units are
matched with an outdoor heat pump unit to create a mini-
split system that uses HFC-410A refrigerant.
MLA/MPA/MPB and
MWMA/MWMB Series
SINGLE-ZONE MINI-SPLIT SYSTEMS
(115V and 208/230V) --
Wall-Mounted Indoor Unit
507545-06
4/2017
Supersedes 10/2016
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 ........................................................8
Outdoor Unit ................................................................8
Indoor Unit ...................................................................8
Torque Requirements for Caps and Fasteners...............9
Indoor Unit Installation ....................................................9
Unit Placement Considerations ...................................9
Determining Wall Mounting Plate Location ..................9
Installation of Wall Mounting Plate...............................9
Installation of Wall Sleeve..........................................10
Installation of Indoor Unit on Wall Mounting Plate .....10
Indoor Unit Condensate Piping Connections .............12
Outdoor Unit Installation ...............................................12
Placement Considerations .........................................12
Direct Sunlight, Rain, Snow and Ice Protection .........13
Prevailing Winds ........................................................14
Buried Refrigerant Pipe Protection ............................14
Outdoor Unit Condensate Piping ...............................14
Securing the Outdoor Unit .........................................15
Refrigerant Piping Connections ....................................15
Leak Test and Evacuation ............................................18
Leak Test ...................................................................18
Triple Evacuation Procedure......................................18
Wiring Connections ......................................................18
Outdoor Unit .............................................................18
Indoor Unit .................................................................18
Unit Start-Up .................................................................26
Adding Refrigerant for Longer Line Set ........................26
Troubleshooting ............................................................26
Test Run .......................................................................26
Pre-Checks ................................................................26
Procedure ..................................................................26
Double-Check Pipe Connections ...............................27
If Ambient Temperature is below 63°F (17°C) ...........27
Dry Mode Operation (Dehumidication) .......................27
Procedure ..................................................................27
Sequence of Operation ..............................................27
THIS MANUAL MUST BE LEFT WITH THE OWNER
FOR FUTURE REFERENCE

Lennox MWMA018S4-2P Specifications

General

Model	MWMA018S4-2P
Phase	1
Type	Air Conditioner
Cooling Capacity	18000 BTU/h
Refrigerant	R410A
Voltage	208-230V
Hertz	60 Hz

Summary

General Information

Safety Warnings and Precautions

Crucial safety warnings regarding installation, service, and product hazards.

IndoorOutdoor Unit Match-Ups

System Clearances

Torque Requirements

Fastener Torque Specifications

Indoor Unit Installation

Unit Placement Considerations

Determining Wall Mounting Plate Location

Wall Mounting Plate Installation

Indoor Unit Installation Procedures

Wall Sleeve Installation

Indoor Unit Mounting Procedure

Indoor Unit Condensate Piping

Outdoor Unit Installation

Outdoor Unit Placement Considerations

Securing the Outdoor Unit

Outdoor Unit Mounting Options

Refrigerant Piping Connections

Making Flare Nut Connections

Steps for connecting and tightening flare nut connections.

Refrigerant Piping Details

Flare Nut Torque Specifications

Recommended torque values for flare nut connections.

Leak Test and Evacuation

System Leak Testing

Procedure for testing the system for refrigerant leaks.

Triple Evacuation Procedure

Steps for evacuating the system using a micron gauge.

Wiring Connections

Outdoor Unit Electrical Connections

Guidelines for connecting power wiring to the outdoor unit.

Indoor Unit Wiring Guidelines

Instructions for indoor unit power and communication wiring.

Outdoor Unit Wiring Diagrams

Unit Start-Up

Pre-Start Up Checks

Essential checks before energizing the unit for start-up.

Start-Up Procedure

Step-by-step guide for initiating unit operation.

Refrigerant Management

Adding Refrigerant for Line Sets

Troubleshooting

Troubleshooting Codes

List of error codes and their descriptions for diagnosing issues.

Test Run Procedure

Double-Check Pipe Connections

Dry Mode Operation

Dry Mode Procedure