Part Name
Check Points
3-way valve
A
B
AB
A
A
B
A
B
Motor
Valve
Indicator (red)
Release button
B
<DHW>
<Heating>
AB
(1) Check the movement of the red indicator. The red indicator normally points
to A in DHW mode and to B in Heating mode as shown to the left.
(2) If each indicator position is correct but the 3-way valve does not work prop
-
erly, the motor may not fit onto the valve securely, so remove the motor by
pressing the release button, and reinstall it.
Thermistors
Disconnect the connector then measure the resistance with a tester.
(At ambient temperatures of 10 - 0°C.)
Thermistor
Normal
Abnormal
TH1
4.3 - 9.5 kΩ
Open or short
TH
THW1
THW
THW5
THW6
THW7
THW8
THW9
THWB1
40 - 100 kΩ
Open or short
THWB
• Boiler flow water temperature thermistor (THWB1)
• Boiler return water temperature thermistor (THWB2)
0
10
20
30
40
50
-20 -10 0 10 20 30 40 50
Temperature (
)
Resistance (k
)
<Thermistor Characteristics Charts>
• Room temperature thermistor (TH1)
• Liquid refrigerant temperature thermistor (TH2)
• Flow water temperature thermistor (THW1)
• Return water temperature thermistor (THW2)
• DHW tank temperature thermistor (THW5)
• Zone 1 flow water temperature thermistor (THW6)
• Zone 1 return water temperature thermistor (THW7)
• Zone 2 flow water temperature thermistor (THW8)
• Zone 2 return water temperature thermistor (THW9)
0°C
15kΩ
10°C
9.6kΩ
20°C
6.3kΩ
25°C
5.2kΩ
30°C
4.3kΩ
40°C
3.0kΩ
Thermistor R0 = 15k
Ω
± %
B constant = 480 ± %
Rt = 15exp {3480 (
7+t
–
7 )}
1
1
0
100
200
300
400
500
600
700
800
900
1000
-30 -20 -10 0
10 20 30 40 50 60 70 80
Temperature (°C)
Resistance (kΩ
)
0°C
162.8kΩ
10°C
97.4kΩ
20°C
60.3kΩ
25°C
48.1kΩ
30°C
38.6kΩ
40°C
25.4kΩ
50°C
17.1kΩ
60°C
11.9kΩ
70°C
8.4kΩ
80°C
6.0kΩ
Thermistor R100 = 3.3kΩ ± 2%
B constant = 970 ± 1%
Rt = 3.3exp {3970 (
7+t
–
7 )}
1
1
66
67
OCH531
Содержание ecodan EHPT20X- VM2HB
Страница 89: ...89 OCH531 ...
