Mitsubishi Electric PUZ-HA30NHA4 Service Manual page 47

10-7. HOW TO CHECK THE COMPONENTS
<Thermistor feature chart>
Low temperature thermistors
• Thermistor <Outdoor pipe> (TH)
• Thermistor <Outdoor -phase pipe> (TH6)
• Thermistor <Outdoor> (TH7)
• Thermistor <Outdoor pipe> (TH)
• Thermistor <Outdoor pipe> (TH)
Thermistor R0 = 1k' ± %
B constant = 80 ± %
1
=1exp{80( 7+t – 7 )}
t (:): R
t
T (˚F): R =1exp{80( 7+(T– )/1.8 – 7 )}
T
15k'
0:[32˚F]
9.6k'
10:[50˚F]
6.3k'
0:[68˚F]
5.2k'
:[77˚F]
Medium temperature thermistor
• Thermistor <Heatsink> (TH8)
Thermistor R0 = 17k' ± %
B constant = 170 ± %
1
t (:): Rt =17exp{170( 7+t –  )}
=17exp{170( 7+(T– )/1.8 –  )}
T (˚F): R
T
180k'
0:[32˚F]
50k'
:[77˚F]
17k'
0:[122˚F]
8k'
70:[158˚F]
4k'
90:[194˚F]
High temperature thermistor
• Thermistor <Discharge> (TH)
Thermistor R10 = 7.6k' ± %
B constant = 07 ± %
t (:): Rt =7.6exp{07( 7+t – 9 )}
=7.6exp{07( 7+(T– )/1.8 – 9 )}
T (˚F): R
T
250k'
0:[68˚F]
160k'
0:[86˚F]
104k'
0:[104˚F]
70k'
0:[122˚F]
48k'
60:[140˚F]
1
1 1
4.3k'
0:[86˚F]
3.0k'
0:[104˚F]
1
1 1
1 1
1 1
34k'
70:[158˚F]
24k'
80:[176˚F]
17.5k'
90:[194˚F]
13.0k'
100:[212˚F]
9.8k'
110:[230˚F]
50
40
30
20
10
0
-20 -10 0 10 20 30 40 50
-4 -14 32 50 68 86 104122 °F
200
150
100
50
0
500
400
300
200
100
0
7
Temperature
25 50 75 100 110 125
77 122 167 212 230 257 °F
Temperature
25 50 75 100
122 167 212
77
Temperature
120
°
248 F