CLIMAVENETA ACCURATE, Руководство пользователя и по обслуживанию

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9
English 01/07
ACCURATE AX* - AW*
CALIBRATING THE THERMOSTATIC VALVE
(air-cooled models)
The thermostatic valve is calibrated using the adjustment screw
shown in the figure; in the water-cooled models, the correct cali-
bration is already performed in the factory.
• Check that the subcooling of the liquid at the condenser
outlet is around 3-5°C;
• Check that the thermostatic valve superheating value is cor-
rect (around 5 °C);
• Check that the valve sensor bulb is correctly positioned, secu-
red and insulated.
If the superheating is above the value indicated previously, open
the valve further; if it is lower, close the valve further.
NOTE: the thermostatic valve must only be calibrated by
specialist personnel.
OPERATION AND CONTROL
A I U
WATER-COOLED UNITS
Water in an open circuit
If the temperature of the cooling water is not controlled and may
fall below 25°C, a pressure control valve is required (available as
an accessory) for each condenser; in this case, the supply pressu-
re must not be less than 200 kPa (2 bar).
IMPORTANT: do not use water cooled using an evaporative
tower, as the condensers will rapidly become fouled by lime scale.
Water in a closed circuit
The condensers on the units are supplied with water pumped in
a closed circuit and cooled by external radiators; check that the
cross-section of the pipes and that the characteristics of the cir-
culating pump are suitable: an insufficient water flow-rate affects
the performance of the air-conditioner.
The temperature of the cooling water must be controlled so as
to not fall below 25°C, preferably according to the diagram
shown in the figure.
IMPORTANT: the cooling water must contain a percen-
tage of ethylene glycol (passivated and consequently non-
corrosive) according to the minimum expected outside
temperature.
In the Energy Saving models, the use of glycol is always
required.
-4°C -10°C -17°C -25°C -37°C
10% 20% 30% 40% 50%
Freezing point (°C)
Percentage of ethylene glycol by weight
B
C
A
25 °C
adjustment screw