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25
42N_S 42N_E
English
The units can be equipped, on demand, with one of the four available
types of controls.
Controls are of the electronic type with microprocessor control.
The controls can be wall-mounted.
Each control can manage one single unit; using A and B controls and an
optional auxiliary board several units can be managed by one control,
see accessories.
All controls must be opened and installed only by qualified personnel as
they contain electrical and electronic components, connected to 230V
power supply.
WARNING:
t
Disconnect the power supply before opening the control cover
t
All inputs (external contact, seasonal changeover etc.) must be
electrically insulated consistent with 230V requirements.
Unit with AC motors
Type “
A
” control is used in 2-pipe systems.
Type “
B
” control is used in 4-pipe systems and 2-pipe systems with
electric heater.
Controls “A” - “B” - “C” - “D”
Unit with EC motors
The “
C
” -type control is used for 2-pipe systems.
The “
D
”-type control is used for 4-pipe and 2-pipe systems with electric
heater.
The controls keep the internal temperature set by means of the knob
between 10 °C and 30 °C.
Control characteristics
Type
A
C
B
D
ON/OFF
Three fan speeds manually selected
Fan speed automatically selected
Temperature selector
Blue LED – cooling operation
Red LED – heating operation
Yellow LED – automatic seasonal changeover
Yellow LED – energy saving
Manual seasonal changeover button
Central seasonal changeover
Automatic seasonal changeover button
Energy saving button
Return air temperature sensor
Temperature sensor located on the board
Cooling / Heating valve outlet (2-pipe)
Heating valve outlet (4-pipe)
Cooling valve outlet (4-pipe)
Electric heater outlet
Frost-protection
External contact
Water minimum temperature sensor
Air sampling (periodic fan starting)
Continuous ventilation
Temperature block
Autotest
Supplementary heating