Lennox MHA018S4S-1P User Manual

1
MINI-SPLIT SYSTEMS SERVICE MANUAL
MHA Series Unit Information
CORP1913-L8
11/2020
Table of Contents
1. Indoor Units ................................................3
1.1. ModelNumberIdentication ..................................... 3
1.2. IndoorUnitSpecications ......................................... 3
1.3. IndoorUnitDimensions ............................................4
1.4. IndoorUnitClearances ............................................. 4
1.5. IndoorUnitWallMounts ...........................................5
1.6. Indoor/OutdoorMatches ........................................... 5
2. Air Throw Data ...........................................6
3. Power and Communication Wiring for
Systems .....................................................7
3.1. Overview ...................................................................7
3.2. WireGauge...............................................................7
3.3. TerminalConnections ...............................................8
4. Indoor Unit Diagrams ................................8
5. Wireless Remote ........................................ 9
5.1. Requirements ...........................................................9
5.2. RemoteControlSpecications .................................9
6. Connection to Centralized Controller .... 11
6.1. SetIndoorUnitAddressforCentralizedControl(Used
withVRFOnly) ........................................................ 11
6.2. IndoorUnitConnectionPointsforCentralized
Controller ................................................................12
6.3. DryModeOperation-IndoorUnits .........................12
6.3.1. Procedure .................................................12
6.3.2. DryModeOperationSequence ................13
6.4. TestRun-IndoorUnits ........................................... 13
6.4.1. TestRunInstructions ................................13
6.4.2. BeforeTestRun ........................................13
6.5. Double-CheckPipeConnections ............................13
6.6. AmbientTemperatureisBelow63°F(17°C) ........... 13
7. Single Zone Outdoor Units .....................15
7.1. ModelNumberIdentication ................................... 15
7.2. Specications..........................................................15
7.3. CoolingandHeatingCapacities .............................16
7.3.1. Cooling-009(115V) ................................16
7.3.2. Heating-009(115V) ................................17
7.3.3. Cooling-009(208/230V) .........................17
7.3.4. Heating-009(208/230V) ......................... 18
7.3.5. Cooling-012(115V) ................................18
7.3.6. Heating-012(115V) ................................19
7.3.7. Cooling-012(208/230V) .........................19
7.3.8. Heating-012(208/230V) ......................... 20
7.3.9. Cooling-018(208/230V) .........................20
7.3.10. Heating-018(208/230V) ......................... 21
7.3.11. Cooling-024(208/230V) .........................21
7.3.12. Heating-024(208/230V) ......................... 22
MHA Single Zone Air
Conditioning Outdoor Unit
MWHA Wall Mount Single Zone
Air Conditioning Indoor Unit
Please refer to Corp1914-L8 for indoor and outdoor unit error codes and component diagnostics.

Lennox MHA018S4S-1P Specifications

General

Model	MHA018S4S-1P
Cooling Capacity	18000 BTU
Refrigerant	R-410A
Voltage	208/230V
Phase	1
Compressor Type	Inverter
Type	Mini-Split Heat Pump
Indoor Unit Type	Wall Mounted

Summary

Indoor Units

1.1. Model Number Identification

Identifies MHA series indoor unit model numbers and their components.

1.2. Indoor Unit Specifications

Provides detailed technical specifications for various indoor unit models.

1.6. Indoor/Outdoor Matches

Details compatible indoor and outdoor unit pairings and their performance ratings.

Power and Communication Wiring

3.2. Wire Gauge

Centralized Controller Connection

6.1. Set Indoor Unit Address

6.2. Indoor Unit Connection Points

Indoor Unit Operations

6.4. Test Run Procedures

Instructions for performing test runs, including pre-checks and post-checks.

Single Zone Outdoor Units

7.1. Model Number Identification

7.2. Specifications

7.3. Cooling and Heating Capacities

Provides detailed cooling and heating capacity data for different operating conditions.

Refrigeration Pipe Work

8.1. Refrigerant Cycle Diagram

8.2. Piping Limitations

Outdoor Unit Connections

9.1. Pipe Length and Torque Requirements

System Wiring

Outdoor Unit Diagrams

Installation Requirements

12.1. Leak Checks and Air Purging

Describes leak checking methods and the procedure for purging air and moisture.

12.4. Refrigerant Addition

Instructions for adding refrigerant based on pipe length and system type.

12.5. System Operation Refrigerant

Electronic Functions

14. Adding Refrigerant - Single-Zone Systems

Guidance on calculating and adding refrigerant for single-zone systems based on pipe length.

Specifications and Operations

16.1. Cooling Chart

16.2. Heating Chart

16.3. Capacity Calculations

Unit Disassembly

17.1. Indoor Unit Disassembly

Step-by-step instructions for disassembling the indoor unit's front panel, filters, and electrical parts.

17.2. Outdoor Unit Disassembly

Instructions for removing panel plates, covers, and components from the outdoor unit.