Daikin REYQ-AATJA, Service Manual, Page: 171 / 495

SiUS372201EA Outline of Control (Indoor Unit)
Part 4 Functions and Control 164
 Assuming suction temperature has changed from 30°C (86°F) to 18°C (64°F) (F

A):
Suction air thermistor is used for temperatures from 30

C (86

F) to 25

C (77

F) (F

D).
Remote controller thermistor is used for temperatures from 25

C (77

F) to 21

C (70

F) (D

B).
Suction air thermistor is used for temperatures from 21

C (70

F) to 18

C (64

F) (B

A).
Heating
When heating, the hot air rises to the top of the room, resulting in the temperature being lower near
the floor where the occupants are. When controlling by suction air thermistor only, the indoor unit
may therefore be turned off by the thermostat before the lower part of the room reaches the set
temperature. The temperature can be controlled so the lower part of the room where the occupants
are does not become cold by widening the range in which remote controller thermistor can be used
so that suction temperature is higher than the set temperature.
 Assuming the set temperature in the figure above is 24°C (75°F), and the suction
temperature has changed from 18°C (64°F) to 28°C (82°F) (A

D):
(This example also assumes there are several other air conditioners, and the suction temperature
changes even when the thermostat sensor is off.)
Suction air thermistor is used for temperatures from 18°C (64°F) to 25°C (77°F) (A

C).
Remote controller thermistor is used for temperatures from 25°C (77°F) to 28°C (82°F) (C

D).
 Assuming suction temperature has changed from 28°C (82°F) to 18°C (64°F) (D

A):
Remote controller thermistor is used for temperatures from 28°C (82°F) to 23°C (73°F) (D

B).
Suction air thermistor is used for temperatures from 23°C (73°F) to 18°C (64°F) (B

A).
Range in w hich remote controller
thermistor can b e u sed
Range in w hich
s u ction air thermistor
can b e u sed
Differential
S u ction air temperat u re (TH1)
Set temperat
u
re (Ts)
12 14 16 18 20 22 24 26 28 30 32 34
53.6 57.2 60.8 64.4 68.0 71.6 75.2 78.8 82.4 86.0 89.6 93.2
°
C
°
F
°
C
32
30
28
26
24
22
20
18
16
°
F
89.6
86.0
82.4
78.8
75.2
71.6
68.0
64.4
60.8
TH1 = Ts + 12
≤
33
°
C
TH1 = Ts + 21.6
≤
91.4
°
F
TH1 = Ts + 10
≤
31
°
C
TH1 = Ts + 18
≤
87.8
°
F
TH1 = Ts + 1
≤
31
°
C
TH1 = Ts + 1.8
≤
87.8
°
F
TH1 = Ts – 1
°
C
TH1 = Ts – 1.8
°
F