4. Service procedures
Check Pin
1.Thermistor checks
The checks listed below are performed for 1 second each, in order from the top down. The results are displayed by LED 1 and 2.
Thermistor |
| Check results | |
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Normal |
| Abnormal | |
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Discharge temp. (TD) | LED 1 lit |
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Outdoor air temp. (TO) | LED 2 lit |
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Heat exchanger temp. (C1) | LED 1 lit |
| LED 1 and 2 OFF |
Heat exchanger temp. (C2) |
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Intake temp. (TS) | LED 1 lit |
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2. |
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3. | Forced cooling (or heating) operation |
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(1) Outdoor Air Temp. (TO), Intake Temp. (TS), Heat | (2) Discharge Temp. (TD) Sensors | |
| Exchanger Temp. (C1) Sensor, Heat Exchanger |
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| Temp. (C2) Sensor |
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Resistance (kΩ) | Resistance (kΩ) |
Temperature (˚F)
4
Temperature (°F)