Midea ESG-Inv M Series User Manual

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ESG‐InvM
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Part4 ‐ Control
3.3 Cooling
Component Wiringdiagramlabel Controlfunctionsandstates
Invertercompressor  COMP Compressorstartupprogramselectedaccordingtoambienttemperature
DCfanmotor FAN Fanrunatmaximumspeed
Electronicexpansionvalve  EXV
Position (steps) from 0 (fully closed) to 480 (fully open), controlled according to
outdoorambienttemperature,dischargetemperature,suctionsuperheat,compressor
speedandrefrigerantsystempressure
Four‐wayvalve 4‐WAY Off
4 Normaloperation
4.1 Heating
Component Wiringdiagramlabel Controlfunctionsandstates
Invertercompressor 
COMP
Controlled according to load requirement from temperature set and outlet water
temperature
DCfanmotor FAN
Controlledaccordingtooutdoorheatexchangerpipetemperature
Electronicexpansionvalve EXV
Position (steps) from 0 (fully closed) to 480 (fully open), controlled according to
outdoorambienttemperature,dischargetemperature,suctionsuperheat,compressor
speed,refrigerantsystempressureandtemperature
Four‐wayvalve 4‐WAY On
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4.2 Cooling
Component Wiringdiagramlabel Controlfunctionsandstates
Invertercompressor 
COMP
Controlled according to load requirement from set temperature and outlet water
temperature
DCfanmotor FAN
Controlledaccordingtooutdoorheatexchangerpipetemperature
Electronicexpansionvalve EXV
Position(steps)from0(fullyclosed)to480(fullyopen),controlledaccordingtooutdoor
ambient temperature, discharge temperature, suction superheat, compressor speed
andrefrigerantsystempressure
Four‐wayvalve 4‐WAY Off
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4.3 Component
• Compressor
The compressorrotationspeed is controlledaccording to the load requirement. Beforecompressor startup,heat pump
determinesthecompressortargetspeedaccordingtooutdoorambient temperature, inlet water set temperature and
actualinletwatertemperatureandthenrunstheappropriatecompressorstartupprogram.Oncethestartupprogramis
completed, the compressor runs at the target rotation speed. During operation the compressor speed is controlled
accordingtotherateofchangeinwatertemperature,therefrigerantsystempressureandtherefrigeranttemperature. 
The running speed of six‐pole compressors in rotations per second (rps) is one third of the frequency (in Hz) of the
electricalinputtothecompressormotor.Thefrequencyoftheelectricalinputtothecompressormotorscanbealteredat
arateof1Hzpersecond.
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• ElectronicExpansionValveControl
Thepositionoftheelectronicexpansionvalve(EXV)iscontrolledinstepsfrom0(fullyclosed)to480(fullyopen). 
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Atpower‐on:TheEXVfirstclosesfully,thenmovestothestandbyposition(480(steps)).AftercompressorrunstheEXVis
controlledaccordingtosuctionsuperheatdischargetemperature,pressure,dischargetemperatureandcompressorspeed.
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Whentheoutdoorunitisinstandby:TheEXVisatposition480(steps).
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MBT Confidential

Midea ESG-Inv M Series Specifications

General

Brand	Midea
Model	ESG-Inv M Series
Category	Heat Pump
Language	English