8-3-2. Refrigerant Control
(1)Thermistor 1
1)Initial check:
Must be able to confirm temperature increase of 2°F (1°C) within approximately 1 minute. Objectives: 1. To detect error in switching reversing valve
2.To detect disconnection of Thermistor 1
2)Limit on amount of combustion at low temperature:
When starting up at low temperature, this function prevents rapid increase in temperature of refrigerant.
1.Minimum combustion at 50°F (10°C) or below
2.Limits combustion up to 70% of the maximum rated power at 95°F (35°C) or below
3)Bypass valve operation:
Opens the bypass valve at 117°F (47°C) and reduces power consumption.
4)Limit on amount of combustion at high load:
● Limits amount of combustion at 144°F (62°C)
Resets when temperature decreases to 140°F (60°C).
● Stops combustion at 149°F (65°C)
Resets when the temperature decreases to 131°F (55°C). (Compressor continuously operates.) Error stop occurs after combustion stops eight times. (Operation lamp on indoor unit blinks.)
(2)Thermistor 2
1)Limit on amount of combustion:
Limits combustion when temperature exceeds 131°F (55°C). The range is proportionally controlled between the minimum and maximum temperatures.
2)Combustion stop:
Stops combustion when temperature exceeds 185°F (85°C).
Error stop occurs after combustion is interrupted (stops) eight times. (Operation lamp on indoor unit blinks.)
3)Detection of bypass valve operation
Must be able confirm temperature increases 5°F (3°C) within approximately 1 minute.
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