Douwe Egberts Cafitesse 700, Back Office Manual

Page: 219 / 265

July 2004
5F - 17
Functions - cooling system
Temperature regulation – cooling system
ON/OFF control:
• Without regulating the cooling compartment
temperature in any form, the system would
possess a constant temperature difference
(typically approx. 26
°
C/79
°
F) between the
surroundings and the cooling compartment.
• As the permissible minimum temperature for
the concentrate is 2
°
C (36
°
F), at ambient
temperatures < 28
°
C (82
°
F) the refrigerat-
ing capacity must be interrupted tempora-
rily. This is carried out by the temperature
regulation system. (Temperature sensor/
switching transistor/microprocessor).
Cooling control
Characteristics of one cooling unit consisting of two peltier elements
Peltier current@ A
5
4.65
4.0
3.0
2.2
2.1
2.0
0.2
Specification
approx. 3.1
Specification
approx. 1.0
Area within
Stand-by specification
Area within
ON specification
Code 33/34 (Stand-by mode)
Peltier current too low
Code 35/36 (Stand-by mode)
Peltier current too high
Code 33/34 (ON mode)
Peltier current too low
Code 35/36 (ON mode)
Peltier current too high
Stand-by = 9W ON = 75W OFF
Standard operational area
1 °C 2 °C 2.5 °C
2.3 °C
3 °C Temperature in cooling box
• Via a temperature sensor (2), the electronic
control system determines the temperature
of the cooling compartment. The cooling
system remains switched on until the
standby temperature is reached (2.5
°
C/
36.5
°
F). Afterwards, the cooling system is
switched to standby until the temperature
rises to 3
°
C (37
°
F) due to the buildup of
heat from the surroundings. If the tempera-
ture drops below 2.3
°
C (36
°
F) in the
standby mode, the cooling system switches
off until the temperature rises above 2.5
°
C.
During the beverage delivery operation, the
cooling system is interrupted. (Fig. 1)
Cafitesse 700 - Functions - cooling system