American Standard 4A6V8024A1000B, Service Facts

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20 4A-V8-SF-1G-EN
Coil and Suction Temperature
Sensor
TEMP F TEMP C
THERMISTOR
RESISTANCE
(OHMS)
VOLTS DC
-15 -26.11 135976 2.71
-10 -23.33 115112 2.64
-5 -20.56 97745 2.56
0 -17.78 83247 2.48
5 -15.00 71108 2.38
10 -12.22 60916 2.29
15 -9.44 52334 2.19
20 -6.67 45088 2.08
25 -3.89 38952 1.97
30 -1.11 33742 1.86
35 1.67 29307 1.75
40 4.44 25520 1.64
45 7.22 22280 1.53
50 10.00 19499 1.42
55 12.78 17108 1.32
60 15.56 15045 1.22
65 18.33 13262 1.13
70 21.11 11717 1.04
75 23.89 10375 0.96
80 26.67 9207 0.88
85 29.44 8188 0.81
90 32.22 7297 0.74
95 35.00 6516 0.68
100 37.78 5830 0.62
105 40.56 5227 0.57
110 43.33 4695 0.52
115 46.11 4224 0.47
120 48.89 3808 0.43
125 51.67 3439 0.40
130 54.44 3111 0.36
135 57.22 2820 0.33
140 60.00 2559 0.30
Figure 8. Coil Temperature Sensor
Pins 2 & 11 (Yellow)
1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18
The Coil Temperature Sensor control has an NTC
thermistor input for sensing the coil temperature. This
reading is used by the defrost algorithm on heat pump
units. The thermistor has a nominal resistance of 10k
ohms at 75°F. The minimum range and resolutions as
measured across pins 2 and 11 required for Coil
Temperature Sensor is —50°F to 150°F
A working Coil Temperature Sensor is required for the
following:
• Defrost Initiation and Termination
• Compressor Sump Heat (Preheating)
• Diagnostics; Charge Level, Indoor/Outdoor Airflow
Figure 9. Suction Temperature Sensor
Pins 3 & 12 (Orange)
1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18
The Suction Temperature Sensor control utilizes an
NTC thermistor input for sensing the suction/gas
temperature. The thermistor has a nominal resistance
of
≈ 10k ohms at 75°F. The minimum range and
resolutions as measured across pins 3 and 12 required
for the Suction Temperature Sensor is —50°F to 150°F
A working Suction Temperature Sensor is required for:
• Outdoor EEV Control (Target Super Heat)
• Diagnostics; Charge level, Indoor/Oudoor Airflow
S SE EN NS SO OR RS S