Service Manual

14
2. Sequence Flow Charts
a) Refrigerator
Refrigerator Sequence Flow Chart
Legend: Comp-compressor ConFM-condenser fan motor CTh-cabinet thermistor DTh-defrost thermistor EvapFM-evaporator fan motor MH-mullion heater
1. Startup/Cool Down
2. Cool Down Achieved
Comp energized ConFM energized EvapFM energized MH energized
CTh in control
Slight Delay at Startup
CTh cools to 3°F (1.7°C) below setpoint. Factory default 36°F (2°C)
CTh warms to 3°F (1.7°C) above setpoint
4. Defrost
DTh cools to 8.6°F(-13°C)
EvapFM energized MH energized Comp de-energized ConFM de-energized
5. Defrost Termination
DTh warms to 40°F (4.4°C)
Note: a) EvapFM de-energizes when door is opened on FS and when upper door is opened on HS. b) 2-minute minimum Comp on timer starts when Comp energizes. c) 2-minute minimum Comp off timer starts when Comp de-energizes. d) 2-minute temperature display delay timer starts when defrost termination temperature is met. e) 20-minute minimum defrost time. f) 1-hour maximum defrost time.
DTh in control
Power on
EvapFM energized MH energized Comp de-energized ConFM de-energized
2-min. Comp off timer starts
EvapFM energized MH energized
2-min. Comp on timer starts
2-min. temperature display
delay timer starts
Comp energized ConFM energized EvapFM energized MH energized
3. Cool Down Restart