Defrost Control - Sanyo C4272R Service Manual

Defrost control

Defrost control
Defrost sequence
Heating operation
(25-minute mask)
1
Frost detection
Defrost start
(reverse cycle defrost)
Defrost in progress
2
Defrost cancel
3 Start-up operation
1
(1) Frost detection
1. Outdoor heat exchanger temperature (C1) method (15-minute mask after operation start)
2
3
2. Outdoor air temperature is 7°F or above and outdoor heat exchanger temperature (C1) of 0°F or below is
4
detected continuously for 20 seconds.
3. Outdoor air temperature is below 7°F and outdoor heat exchanger temperature (C1) of below (outdoor air
temperature -10)°F is detected continuously for 20 seconds.
(2) Defrost cancel
• Defrost end conditions
1. Outdoor heat exchanger temperature (C1) rises to 54°F or higher.
2. Outdoor heat exchanger temperature is 45°F or higher continuously for 1 minute.
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3. Defrost time of 10 minutes has elapsed.
(3) Startup operation
After defrost ends, the compressors and outdoor unit fan stop for approximately 40 seconds, then operation begins
in heating mode.
6
•
Operating frequency: 61.8 Hz
•
Outdoor unit fan: OFF
•
Electronic control valve: step 300
• 4-way valve: OFF
•
Indoor unit fan: OFF
II-8
2. Processes and functions
SM831148