York HIDS006B21S - Page 127

(Main Parts)
MAINTENANCE
SM-18001-rev.1
4-53
(2) Thermistor for Indoor Suction Air
Temperature (For Room Temperature
Control)
The room temperature is controlled by the
thermistor for indoor suction air temperature
detecting the temperature at the suction air
inlet of the indoor unit.
The setting temperature is indicated on
the L.C.D. of the wired controller switch by
number.
Adjust the setting temperature for prevention
from excessive cooling and heating.
It is recommended to set the temperature as
follows;
Economical Cooling Operation: 81
o
F (27
o
C) to 84
o
F (29
o
C) / Economical Heating Operation: 64
o
F
(18
o
C) to 68
o
F (20
o
C)
The resistance characteristics of thermistor is shown in the above gure.
ATTENTION:
The thermo-off value of the indoor unit air inlet thermistor is set at the temperature higher than the value
indicated on the wired controller switch by 7
o
F (4
o
C) and the maximum is 86
o
F (30
o
C), because the suction
air temperature during heating operation has a tendency to become higher than that of the occupied zone,
intending comfortable heating operation.
(3) Thermistor for Indoor Discharge Air Temperature (For Discharge Air Temperature Control)
The thermistor for indoor discharge air temperature is utilized for the control of prevention from cold air
discharge in heating operation, etc.
The resistance characteristics of thermistor is shown in the above gure.
(4) Thermistor for Liquid Pipe Temperature of Indoor Heat Exchanger
The resistance characteristics of thermistor is shown in the above gure.
(5) Thermistor for Gas Pipe Temperature of Indoor Heat Exchanger
The evaporating temperature in heating operation is detected.
The resistance characteristics of thermistor is shown in the above gure.
When the temperature of the heat exchanger is below 32
o
F (0
o
C),
thermostat is turned OFF automatically and over 57
o
F (14
o
C),
thermostat is turned ON again.
Prevention from freezing
onto the heat exchanger in
COOL and DRY operation.
When the temperature of the heat exchanger is below 32
o
F (0
o
C),
thermostat is turned OFF automatically and over 57
o
F (14
o
C),
thermostat is turned ON again.
Prevention from freezing
onto the heat exchanger in
COOL and DRY operation.
0
10
20
30
40
50
60
70
80
5
(-15)
14
(-10)
23
(-5)
0
(0)
41
(5)
50
(10)
59
(15)
68
(20)
77
(25)
86
(30)
95
(35)
104
(40)
113
(45)
122
(50)
131
(55)
140
(60)
82
61
46
35
27
20.5
16
12.5
10
8
5.3
3.6
2.5
90
Ambient Temperature (
o
C)
Thermistor
Resistance
Thermistor Characteristics