Mitsubishi Electric EHSC-MEC Service Manual page 70

<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)
• Zone1 flow water temperature thermistor (THW6)
• Zone1 return water temperature thermistor (THW7)
• Zone2 flow water temperature thermistor (THW8)
• Zone2 return water temperature thermistor (THW9)
Thermistor R0 = 15kΩ ± 3%
B constant = 3480 ± 2%
1 1
Rt = 15exp {3480 ( 273+t – 273 )}
0°C 15 kΩ
10°C 9.6 kΩ
20°C 6.3 kΩ
25°C 5.2 kΩ
30°C 4.3 kΩ
40°C 3.0 kΩ
• Boiler flow water temperature thermistor (THWB1)
• Boiler return water temperature thermistor (THWB2)
Thermistor R100 = 3.3 kΩ ± 2%
B constant = 3970 ± 1%
1 1
Rt = 3.3 exp {3970 ( 273+t – 273 )}
0°C 162.8 kΩ
10°C 97.4 kΩ
20°C 60.3 kΩ
25°C 48.1 kΩ
30°C 38.6 kΩ
40°C 25.4 kΩ
50°C 17.1 kΩ
60°C 11.9 kΩ
70°C 8.4 kΩ
80°C 6.0 kΩ
OCH571D
50
40
30
20
10
0
-20 -10 0 10 20 30 40 50
Temperature (:)
1000
900
800
700
600
500
400
300
200
100
0
-30 -20 -10 0
70
10 20 30 40 50 60 70
Temperature (°C)
80