Service Manual

11
2. Prep Table: Refrigerator
Prep Table Top Sequence Flow Chart
2. Cool Down
3. Cool Down Achieved
Comp energized ConFM energized EvapFM energized
EvapFM energized Comp de-energized ConFM de-energized
4. Defrost
CTh above setpoint
CTh cools to setpoint
CTh above
setpoint
Defrost Termination: 46°F (7.7°C) achieved or 45 min. backup defrost timer terminated.
CTh in control
1. Startup
EvapFM energized
6-hr. DT terminates 5-min. min. DT starts 45-min. max. DT starts DH energized Comp de-energized ConFM de-energized EvapFM de-energized
Defrost: Time/Temp achieved.
Power on Red LED On (5 sec. Delay)
Red LED Off Green LED Flashes If Red LED Flashes, check CTh or DTh
Legend: Comp-compressor ConFM-condenser fan motor CTh-cabinet thermistor DH-defrost heater DT-defrost timer DTh-defrost thermistor EvapFM-evaporator fan motor
Note: Delays
a) 2-min. minimum Comp on timer starts when Comp energizes. b) 2-min. minimum Comp off timer starts when Comp de-energizes. c) 5-min. minimum defrost time. d) 45-min. maximum defrost time. e) DOT (drip off time) 1-min. Comp/ConFM delay timer starts when defrost termination temperature is met (drip off time (DOT)). f) FDD (fan delay after defrost) EvapFM starts once 30-sec. EvapFM delay timer terminates or DTh reaches 40°F (4.4°C).
g) If evaporator temperature raises above 50°F (10°C) during the cooling cycle, 6-hr. DT resets.
*
2-min. Comp off timer starts
2-min. Comp on timer starts
Evap. Temp. reaches 46°F (7.7°C) DH de-energized 6-hr DT starts After DOT Delay: Comp energized ConFM energized After FDD EvapFM energized
*
*
*
*
*
*
DTh in control
5. Defrost Termination
6-hr. DT terminates
Evap. temp. below 50°F (10°C)
Defrost Terminated