B. Sequence of Operation

The steps in the sequence are as outlined below.

1. Startup

When the power switch is in the "ON" position, the cabinet temperature is displayed and cabinet cooling begins. When the power switch is in the "ON" position and the rail cooling switch is moved to the "NORMAL" or "LOW" position, the rail temperature is displayed and rail cooling begins. The "NORMAL" rail switch position is designed for use when the rail cover is open. The "LOW" rail switch position is designed for use when the rail cover is closed. For further details, see "II.D.4.a) Switch Settings."

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

Cabinet temperature at or above setpoint: CabFM, CLLV, and PH energize. The 2 minute Comp delay timer and 6 hour DT start.

b)Power Switch "ON," Rail Cooling Switch "NORMAL" or "LOW"

Cabinet temperature and rail temperature at or above setpoint: CabFM, CLLV, PH, RailFM, and RLLV energize. The 2 minute Comp delay timer and 6 hour DT start.

2.Cool Down

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

CabFM, CLLV, and PH continue. The 2 minute Comp delay timer expires and Comp and ConFM energize.

b)Power Switch "ON," Rail Cooling Switch "NORMAL" or "LOW"

CabFM, CLLV, PH, RailFM, and RLLV continue. The 2 minute Comp delay timer expires and Comp and ConFM energize.

3.Cool Down Achieved

To prevent Comp hard starts, CLLV (rail cooling switch "OFF") or RLLV (rail cooling switch "NORMAL" or "LOW") remains energized when Comp is off.

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

CTh reaches 3.6°F (2°C) below setpoint. CabFM and PH continue, Comp and ConFM deenergize. CLLV de-energizes for 2 seconds (CLLV then remains energized during Comp off time).

b)Power Switch "ON," Rail Cooling Switch "NORMAL" or "LOW" CTh, RTh, or both have reached 3.6°F (2°C) below setpoint.

(1) Cabinet still cooling, RTh reaches 3.6°F (2°C) below setpoint

CabFM, Comp, CondFM, CLLV, and PH continue. RailFM continues when rail cooling switch is in the "NORMAL" position and per F9 setting when in the "LOW" position. For details, see "II.D.4.a) Switch Settings." RLLV deenergizes.

(2)CTh reaches 3.6°F (2°C) below setpoint, rail still cooling

CabFM, Comp, CondFM, PH, RailFM, and RLLV continue. CLLV de-energizes.

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Hoshizaki 73168 service manual Sequence of Operation, Power Switch ON, Rail Cooling Switch OFF