Tefcold BLC5-P Guide Rapide page 73

11.3 EXAMPLE OF A BLAST CHILLER CYCLE
The following drawing explains how a Blast Chiller cycle can be done.
Temper.
FIRST PHASE:
°C
HARD CHILL
20
15
iS1
10
5
iS2
rS2
0
rS1
-5
-10
-15
iS3
-20
-25
rS3
-30
Insert probe
11.3.1 First phase: "Hard chill".
It is normally used to fast chill hot foods. E.g. from 80°C / 170°F to 20°C / 70°F
During "Hard Chill", both compressor and fan are always on until the rS1 temperature is reached. At this
point compressor is turned on end off so as to keep the temperature of the room at the rS1 value. "Hard
Chill" ends when the temperature measured by the 3 insert probes reach the iS1 value.
11.3.2 Second phase: "Soft chill".
The Soft Chill starts when the Hard Chill ends. It is used to prevent thin layer of ice from forming on the
product. The Soft Chill lasts until the temperature measured by the 3 insert probes reach the set point
iS2 (usually 4 or 5°C).
During Soft Chill the temperature of the room is regulated by the ambient probe with the set point rS2
(normally at 0 or 1 °C / 32 or 34°F). When the box temperature reaches the rS2 value compressor is
turned on end off so as to keep the temperature of the box at this value.
11.3.3 Third phase: "Freezing cycle".
Freezing Cycle: used to fast freeze foods.
The Freezing Cycle starts when the Soft Chill ends. During the "Freezing Cycle" both compressor and
fan are always on until the rS3 temperature is reached. At this point compressor and fans are turned on
end off so as to keep the temperature of the room at the rS3 value (normally some degrees below iS3).
Freezing Cycle ends when the temperature measured by the 3 insert probes reach the iS3 value
(normally -18°C / 0°F), in any case it ends when the maximum time Pd1 + Pd2 + Pd3 has expired.
11.3.4 End of the Blast Chill cycle and starting of the Hold Mode.
When one of the three insert probes reaches the iS3 value the values End followed by the i1P or i2P or
i3P are shown on the display.
Cycle ends when all the probes have reached the iS3 value. A signal is generated: buzzer and alarm
relay is turned ON, the display shows the message "End" alternating with the room temperature.
The alarm automatically stops after the "but" time or by pressing any keys.
At the end of the cycle the controller can start the "Hold mode" keeping the room temperature at the
value set in HdS parameter.
If HdS = OFF, the machine is turned OFF.
NOTE1: with dbH = yES a defrost is done before the holding phase.
1592006207 XB570L GB r1.1 26.08.2015
2 PHASE 3 PHASE
SOFT CHILL FREEZING CYCLE
Room Probe
Time
XB570L
14