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Operation and maintenance instructions
Frost protection heating and cooling coils
The water coils are always protected against freezing by
an anti-frost temperature sensor. This sensor is monted
on the surface of the water coil. When the anti-frost
protection temperature of the hydraulic coil detects a
tempeature lower than °C (default), the pump contact
is closed and the way valve is opened % during
minutes. If the unit is running, the alarm is activated
immediately. For a water preheating coil, the frost alarm
is delayed by minutes. If frost protection conditions
occur when the air handling unit is OFF, the alarm is
delayed by minutes.
Setting Settings
range
Factory
setting
Internal heating coil -10...+10°C +4,0°C
External heating coil -10...+10°C +4,0°C
External cooling coil -10...+10°C +4,0°C
Internal preheating coil -10...+10°C +4,0°C
Freecooling
The bypass on the GLOBAL product range, can be cong-
ured for freecooling. The main parameters to activate the
free cooling function are the outside temperature (T)
and the extract (room) air temperature (T). When there
is maximal freecooling possibility the bypass will be %
open. The % opened bypass can activate the cong-
urable freecooling airow.
Setting Settings
range
Factory
setting
Outdoor T° 0...27°C 10,0°C
Extract/Room T° 6...28°C 22,0°C
Supply airow (l/s, m³/h)
Extract airow (l/s, m³/h)
Bypass control Frost protection
Freecooling
Frost protection &
free cooling
Freecooling
Frost protection
Frost protection plate heat exchangers (PX)
In environments where the extract air can occasionally
be humid, the defrosting function can be activated to
protect the heat exchanger from frosting. There are four
strategies: down control of the supply air volume, modu-
lating by-pass control, modulation of capacity of a pre-
heating coil, dierential pressure measurement (cold cli-
mate option). If non of these measures are eective, the
air handling unit can be stopped by limting the minimal
supply air temperature. When the Frost protection cycle
is active, it will be indicated on the HMI. The congurable
temperatures are exhaust temperatures.
Setting Settings
range
Factory
setting
T° Low 1...3°C +1,0°C
T° High 1...5°C +5,0°C
Stop supply airow No
Yes
Yes
Frost protection rotary heat exchangers (RX)
In environments where the extract air can occasionally
be humid, the defrosting function can be activated to
protect the heat exchanger from frosting. The speed of
the rotating heat exchanger is linked to the tempera-
ture of the outdoor (sensor T). When the Frost pro-
tection cycle is active, it will be indicated on the HMI.
Setting Settings
range
Factory
setting
Activate Frost protection -29...+99°C -9°C
RX rotation speed 2...10RPM 2RPM
Frost protection cycle active
Frost protection alarm
Frost protection Nominal
Rotation speed