Cooling mode (chilled water)
(DIP switch no.8 = OFF)
½ SDC
1
0
½ SDC
w
Y11
30
22
D
02
T [°C]
T[°C] Room temperature
w
Room temperature setpoint
Y11 Manipulated variable«Valve»
Y21 Manipulated variable «Electric heating»
SDH Switching differential ”Heating”
w
D
Setpoint
differential
Xdz Dead zone
SDC Switching differential ”Cooling”
The room temperature setpoint can be limited in increments of 1 K by making use of
the minimum and maximum limitation facility. Arbitrary setpoint readjustments can thus
be presented.
Operating modes
The following operating modes are available:
Heating or cooling mode with automatic changeover and with manually selected fan
speed III, II or I. In normal operation, the controller maintains the adjusted setpoint.
The frost protection function is activated only when DIP switch no.4 is set to OFF.
Frost protection mode can be activated either
•
by manually switching to standby .
•
by activating the external operating mode changeover switch, provided
DIP switch 2 is set to OFF
If the room temperature falls below 8 °C, the controller will automatically switch to frost
protection mode. In that case, the heating valve opens and the fan operates at the se-
lected speed. If the selector is in position standby , the fan will operate at speed I.
The room temperature is maintained at a setpoint of 8 °C and the setpoint adjusted by
the user will be ignored.
If frost protection operation is locked (DIP switch no. 4 in position ON), standby is
locked also, which means that the controller will not switch to standby but to OFF.
In frost protection mode, the electrical heater is always enabled, independent of the
position of DIL switch no.8 ( behaviour of electrical heater in cooling mode).
In energy saving mode, the setpoint of heating is 16°C and the setpoint of cooling
28 °C, independent of the position of the setpoint knob. This operating mode will be
activated when input D1 for operating mode changeover is active and DIP switch no.2
is set to ON.
A changeover switch can be connected to status input D1–GND. When the switch
closes its contact (caused by an open window, for instance), the operating mode will
change from normal operation to energy saving mode (provided DIP switch no.2 is set
to ON), or from normal operation to standby (provided DIP switch no.2 is set to OFF). If
the room temperature falls below 8 °C and if DIP switch no.4 is set to OFF, frost protec-
tion mode will become active.
The operating action of the switch (N.C. or N.O) can be selected.
Ordering
When ordering, please give name and type reference.
The QAH11.1 temperature sensor (can be used as a return air temperature or change-
over sensor), the changeover mounting kit and the zone valve are to be ordered as
separate items.
Energy saver
Normal operation
Frost protection mode
Note
Energy saving mode
Operating mode
changeover switch
4
