Stage 1:
5-minute Comp delay timer

Power Switch "ON," Rail Cooling Switch "OFF"

1. Cabinet

C.

Cycle Steps

1.Startup

2-minute

Comp delay timer starts

6-hour DT starts

 

2. Cool Down

 

3. Cool Down Achieved

 

4. Cabinet Defrost

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

From 5 below

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2-minute Comp

 

 

 

 

 

 

 

 

 

 

DTh in control

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

delay timer starts

 

to

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CTh reaches

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CTh warms setpoint

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

3.6°F (2°C)

 

 

• 6 hour DT expires, then

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

or more

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

resets

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

below setpoint

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

100-minute defrost

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CTh in control

 

 

 

 

 

 

 

 

 

 

 

 

termination timer starts

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Cooling

Sequence of

 

Operation

Initial startup begins here

To 5 below

12

CabFM energized

CabFM energized

CabFM energized

CLLV energized

CLLV energized

CLLV energized

CLLV energized

DH energized

PH energized

Comp energized

PH energized

CabFM de-energized

 

ConFM energized

Comp de-energized

Comp de-energized

 

PH energized

ConFM de-energized

ConFM de-energized

 

 

 

PH de-energized

From 4 above

5.Cabinet Cool Down Defrost Recovery (defrost terminated)

DTh reaches 49°F (9.4°C) or

100-minute defrost termination timer expires or DTst temperature reaches 120°F±5°F (49°C±3°C)

Stage 2:

5-minute CabFM and

PH delay timer

To 2 above

CLLV energized

CabFM and PH

CabFM energized

DH de-energized

energize for 10 sec.

CLLV energized

CabFM de-energized

CLLV energized

Comp energized

Comp de-energized

Comp energized

ConFM energized

ConFM de-energized

ConFM energized

PH energized

PH de-energized

 

 

Legend: CabFM-cabinet fan motor Comp-compressorConFM-condenser fan motor CLLV-cabinet liquid line valve CTh-cabinet thermistor DH-defrost heater DT-defrost timer DTh-defrost thermistor DTst-defrost thermostat PH-perimeter heater

Page 12
Image 12
Hoshizaki 73168 service manual Operation, Power Switch ON, Rail Cooling Switch OFF Cabinet