Basic Control; Normal Operation - Daikin RXYQ-TA Series Service Manual

SiUS341615E

5. Basic Control

5.1

Normal Operation

Tc : High pressure equivalent saturation temperature
Te : Low pressure equivalent saturation temperature
DSH: Discharge pipe superheated degree
Cooling
Part Name
Inverter compressor 1
Inverter compressor 2
Inverter fan 1
Inverter fan 2
Electronic expansion valve
(Main)
Electronic expansion valve
(Injection)
Four way valve
Solenoid valve
(Accumulator oil return)
Solenoid valve (Oil return 1)
Solenoid valve (Oil return 2)
: equipped
–: not equipped
∗1: RXYQ96/120TA only
Heating
Part Name
Inverter compressor 1
Inverter compressor 2
Inverter fan 1
Inverter fan 2
Electronic expansion valve
(Main)
Electronic expansion valve
(Injection)
Four way valve
Solenoid valve
(Accumulator oil return)
Solenoid valve (Oil return 1)
Solenoid valve (Oil return 2)
: equipped
–: not equipped
∗1: RXYQ96/120TA only
Functions and Control
Electric
RXYQ72-120TA RXYQ144/168TA
Symbol
M1C
M2C –
M1F
∗1
M2F ( )
Y1E
Y2E
Y1S
Y2S
Y3S
Y4S –
Electric
RXYQ72-120TA RXYQ144/168TA
Symbol
M1C
M2C –
M1F
∗1
M2F ( )
Y1E
Y2E
Y1S
Y2S
Y3S
Y4S –
Function of Functional Part
PI control by Te target depends on field
setting 2-8 and 2-81.
Fan speed 9 steps to keep minimum Tc
target 34°C (93.2°F).
0 pulse: closed (thermostat OFF),
3,000 pulses: open (thermostat ON).
0-480 pulses at compressor ON
OFF
Close if DSH < 15°C (27°F)
Only close if Pc – Pe < 0.3 MPa (43.5 psi)
(when compressor OFF)
Function of Functional Part
PI control by Tc target depends on field
setting 2-9 and 2-82.
Fan step 7 (normal Tc and Te) or Fan step 8
(high load).
0 pulse: closed (thermostat OFF),
0-3,000 pulses: SH control 5°C (9°F).
0-480 pulses at compressor ON: based on
indoor demand.
ON
Close if DSH < 15°C (27°F)
Only close if Pc – Pe < 0.3 MPa (43.5 psi)
(when compressor OFF)
Basic Control
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