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We reserve the right to make changes without any prior notice.
Translation from original instructions
2.2.4 Installing the flow switch
The units are shipped from the factory with the flow switch installed.
The arrow on the switch must be aligned with the water flow.
2.2.5 Unit operating in heat pump mode
The performance of units in heat pump operation goes down as the external air temperature falls.
The units are fitted with an antifreeze heater to heat the plate heat exchanger and the bottom of the external coil.
This heater gets started when the external air temperature drops below the setpoint temperature of the thermostat that
controls heater operation.
2.2.6 Operation with water to the evaporator at low temperature
With temperatures below 5°C, it is mandatory to work with water and anti-freeze mixtures, and also change the safety devi
-
ces (anti-freeze, etc.), which must be carried out by qualified authorised personnel or by the manufacturer.
The glycol percentage by weight is determined based on the desired temperature of the chilled water (see table).
Minimum ambient temperature or liquid
outlet temperature (°C)
0
-5
-10
-15
-20
-25
-30
-35
-40
Freezing point (°C)
-5
-10
-15
-20
-25
-30
-35
-40
-45
Antifreeze
% by weight
Ethylene glycol
6
22
30
36
41
46
50
53
56
Propylene glycol
15
25
33
39
44
48
51
54
57
If ambient temperatures are expected to be lower than the freezing point of water, it is essential to use an
-
ti-freeze mixtures in the above-mentioned percentages.
In the case of units with pump units applied in systems with glycol percentages above 30%, when ordering,
a request must be made for a technical check for compatibility of the pumps and, if necessary, the best so
-
lution identified, which could require the use of a specific hydraulic module or the application of pumps with
special electric motors.
2.2.7 Operation in heat pump mode with low temperature water
The standard units are not designed to operate in heat pump mode with water temperatures that are too low (refer to the
Techical Catalogue for the limits).
2.2.8 Condensate drain (only for heat pump units)
In heat pump units, condensate is drained through a series of openings located at the base of the external unit. We recom-
mend placing the unit carefully and in such way that condensate is not drained in pedestrian transit areas as this would pose
the risk of condensate freezing if the external air temperature is low and the surface to become slippery.
