Lennox MHA Series Service Manual

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7.4. UnitDimensions......................................................22
7.5. OutdoorUnitClearances ........................................23
7.5.1. SingleUnits ..............................................23
7.5.2. MultipleUnits ............................................24
8. Refrigeration Pipe Work ..........................25
8.1. Single-ZoneRefrigerantCycleDiagram ................. 25
8.2. Single-ZonePipingLimitations ...............................25
9. Outdoor Unit Connections and Line
Set Usage .................................................26
9.1. PipeLength.............................................................26
9.2. TorqueRequirements .............................................26
10. Power and Communication Wiring for
Systems ...................................................27
11. Outdoor Unit Diagrams ...........................28
12. Installation Requirements ....................... 29
12.1. GasLeakCheckwithSoapWater: ......................... 30
12.2. AirandMoisture......................................................30
12.3. AirPurgingusingaVacuumPump .........................30
12.4. AddingRefrigerantifPipeLengthExceeds
ChargeLessPipeLength .......................................30
12.5. AddRefrigerantafterLong-TermSystem
Operation ................................................................ 30
12.6. ServicingIndoorUnitRefrigerationCircuit..............31
12.6.1. CollectingRefrigerantintoOutdoorUnit...31
12.6.2. AirPurgingwithVacuumPump ................ 31
12.7. EvacuationafterServicingtheOutdoorUnit
RefrigerationCircuit ................................................ 31
12.7.1. EvacuationoftheComplete
RefrigerationCircuit,Indoorand
Outdoor Unit ............................................. 31
12.7.2. RefrigerantCharging ................................ 31
13. Electronic Function .................................32
13.1. Abbreviation ............................................................32
13.2. ElectricControlWorkingEnvironment. ...................32
14. Adding Refrigerant - Single-Zone
Systems ....................................................32
15. Single-Zone Outdoor Unit LED
Locations .................................................. 32
16. SpecicationsandOperations ...............33
16.1. CoolingChart ..........................................................34
16.2. HeatingChart..........................................................34
16.3. CapacityRequestCalculations ...............................35
16.4. OutdoorFanControl ............................................... 36
16.4.1. CoolingMode ...........................................36
17. Indoor and Outdoor Unit Disassembly ..37
17.1. IndoorUnit(AllModels) ..........................................37
17.1.1. FrontPanel ...............................................37
17.1.2. ElectricalParts .........................................39
17.1.3. Evaporator ................................................41
17.1.4. FanMotorandFan ...................................42
17.1.5. Step Motor ................................................42
17.1.6. DrainHose ...............................................43
17.2. Outdoor Unit ...........................................................43
17.2.1. PanelPlate(SomeModels)......................43
17.2.2. PanelPlate(MWHA024S4) ......................44
17.2.3. ElectronicComponents(MWHA009S4
andMWHA012S4) ...................................45
17.2.4. ElectronicComponents(MWHA018S4) ... 46
17.2.5. ElectronicComponents(MWHA024S4) ... 46
17.2.6. FanDisassembly(MWHA009S4and
MWHA012S4) ..........................................46
17.2.7. FanDisassembly(MWHA018S4) .............47
17.2.8. FanDisassembly(MWHA024S4) .............48
17.2.9. SoundBlanket .......................................... 49
17.2.10.Four-WayValve ........................................ 49
17.2.11. Compressor ..............................................49

Lennox MHA Series Specifications

General

Brand	Lennox
Model	MHA Series
Category	Air Conditioner
Language	English