Daikin RQYQ140-180PY1, Service Manual, Page: 54 / 231

Detailed Control Functions SiBE341001
45 Function
2.5.6 Heat Exchanger Control
While in heating or cool/heat simultaneous operation, ensure target condensing and evaporating temperature by
changing over the air heat exchanger of outdoor unit to the evaporator or the condenser in response to loads.
[Single system]
[Multi outdoor unit system]
Outdoor unit
Left side
Condenser
Right side
Condenser
GR < -20 GR > 25
Outdoor unit
Left side
Evaporator
Right side
Condenser
GR > 25
GR < -20
Outdoor unit
Left side
Evaporator
Right side
–
Outdoor unit
Left side
Evaporator
Right side
Evaporator
GR < -10 GR > 15
Note 1. "GR" is a numeric value
representing the current
balanced condition and
calculated from target
condensing temperature,
target evaporating
temperature, current
condensing temperature,
and current evaporating
temperature.
A1
A2
A3
A4
Outdoor unit
1 2 3
Condenser Condenser Condenser
GR < -10 GR > 15
Outdoor unit
1 2 3
Condenser Condenser Evaporator
GR < -20 GR > 25
Outdoor unit
1 2 3
Condenser Evaporator
–
GR < -10 GR > 15
Outdoor unit
1 2 3
Condenser Evaporator Evaporator
Note 1. "GR" is a numeric value representing the current balanced
condition and calculated from target condensing temperature,
target evaporating temperature, current condensing temperature,
and current evaporating temperature.
Note 2. On the system with two outdoor units, if there is no step for the
destination of transition, that step will be skipped.
B1
B2
B3
GR > 25
GR < -20
GR > 25
Outdoor unit
1 2 3
–
Evaporator
–
GR < -10 GR > 15
Outdoor unit
1 2 3
Evaporator Evaporator –
GR < -10 GR > 15
Outdoor unit
1 2 3
Evaporator Evaporator Evaporator