User Manual

Functions
Handling system faults
4
90 | 146 A6V11545892_en--_a
# Function of input Description
Type
X1/X2/U1
Presence
detector
10 Presence detector
Presence detector input switches the operating
mode to Comfort when the room is occupied and
switches back to previous operating mode when
the room is unoccupied.
Presence detector is also possible via bus. In this
case, do not assign the function to any local input
X1, X2 or U1. See also Presence detector [➙ 43].
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11
External temperature
limit
The sensor is connected to the pipe and
measures the temperature of the floor heating
water. When the value exceeds the selected limit
(P252), heating is stopped. See also Monitoring
and limitation functions [➙ 47]
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12 Coil temperature
To avoid cooling flow air in the room, the sensor
measures the coil water temperature and
releases the fan only when the selected minimum
hot water temperature limit is exceeded (P366).
See also Fan control [➙ 87].
AI
Hotel
presence
detector
13 Hotel presence detector
Hotel presence detector input switches the
operating mode to Economy when the room is
unoccupied and icon displays (buttons are
locked) and switches back to previous operating
mode when the room is occupied.
Hotel presence detector is also possible via bus.
In this case, do not assign the function to any
local input X1, X2 or U1. See also Presence
detector [➙ 43].
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● Control action can be changed from normally open (NO) and normally closed
(NC) via P151, P154 or P156.
● Each input X1, X2 or U1 must be configured with a different function (1…5 &
9…13). Exception: 1, 2 or 3 inputs can be configured as fault (6) or monitor
input (7,8).
● X1 is factory-set to "External sensor" (1), X2 to "Not used" (0), and U1 to
"Window contact" (3).
For more detailed information, see Applications overview [➙ 36].
● For inputs X1, X2, or U1, one physical switch can be used for up to 20
thermostats (parallel connection).
Caution! DO NOT mix X1/X2 and U1.
● For sensors on inputs X1, X2, or U1, the maximum cable length is 80 m.
4.11 Handling system faults
If the room temperature exceeds or falls below the measuring range, i.e. above
49 °C or below 0 °C, the limiting temperatures blink, for example, 0 °C or 49 °C.
In addition, the heating output is activated if the current setpoint is not set to OFF,
the thermostat is in heating mode and the temperature is below 0 °C.
For all other cases, no output is activated.
The thermostat resumes Comfort mode as soon as the temperature is within the
measuring range.
Note
Temperature out of range