Daikin GQI-Eco Series Service Manual page 43

ESIE15-13B
 Outdoor Unit
 Indoor Unit
Function and Control
(A) Compressor (M1C)
Inverter drive unit varies compressor operating frequency to control capacity and other
factors.
(B) Electronic Expansion Valve (Y1E)
Provides control to maintain optimum operating condition for high efficiency.
(C) Four Way Valve (Y1S)
Changes operation of cooling / heating.
* Coil energized: heating
Coil not energized: cooling
Outdoor Air Thermistor (R1T)
Used for startup condition control and defrost control.
Discharge Pipe Thermistor (R2T)
Used for discharge temperature protection during compression operation.
Suction Pipe Thermistor (R3T)
Used for suction super heat control by electronic expansion valve.
Heat Exchanger Distributor Pipe Thermistor (R4T)
• Used for calculation of outdoor heat exchanger subcooling during cooling operation.
• Used for judgement of the defrost IN and OUT condition.
Intermediate Heat Exchanger Thermistor (R5T)
Used for calculation of high pressure during cooling operation. (Calculate Pc by detected
temperature and R-410A refrigerant characteristics)
Liquid Pipe Thermistor (R6T)
Used for calculation of indoor unit heat exchanger subcooling during heating operation.
Radiation Fin Thermistor (R10T)
• Used for outdoor fan speed control.
• Used for inverter radiation fin temperature control.
• Used for pressure difference control.
R1T Suction air thermistor
R2T
Heat exchanger thermistor
R3T
Indoor Suction Air Thermistor
Cooling: Thermostat control
•
PMV control
•
General frequency control
•
Heating: Thermostat control
•
PMV control
•
General frequency control
•
Indoor Heat Exchanger Thermistor
Cooling: Compressor frequency control (target Te)
•
Inverter current protection control
•
Freeze-up control
•
Heating: Compressor frequency control (target Tc)
•
Inverter current protection control
•
Hot start control
•
Peak cut-off
•
Function of Main Components and Thermistors
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