ID Alarm
Cause
System reaction
Remedy
6 Frost protection
The temperature has fallen to below
11 °C after the heating coil.
The mixing valve heating opens contin-
uously. The (optional) heating pump
switches on.
Check the heat supply and the
unit hydraulics, rectify error.
Reset alarm.
The temperature has fallen to below
5 °C after the heating coil.
The 'frost protection' alarm is tripped.
The heating mixing valve opens 100%.
The unit switches off.
9 Forced switch-off unit
An external signal has activated the
forced switch-off function.
The unit switches off.
Deactivate the external signal.
Reset alarm.
10 Forced switch-off zone
An external signal has activated the
forced switch-off function.
All units in the zone switch off.
202 Fresh air filter maintenance
(operating hours)
The operating hours for the mainte-
nance reminder have been reached.
–
Check the filter and renew it if
necessary.
Reset alarm.
206 Filter maintenance (operating hours)
The operating hours for the mainte-
nance reminder have been reached.
–
Check the filter and renew it if
necessary.
Reset alarm.
208 Air filter maintenance
The pressure difference for filter
monitoring was exceeded for more than
2 minutes.
–
Change the filter.
Reset alarm.
220 Fault supply air temperature sensor
shortcut
The sensor or the cabling has a short
circuit.
The unit switches to L_REC operating
mode and controls using the extract air
temperature.
The unit switches off if the extract air
sensor fails at the same time.
Rectify fault.
Reset alarm.
221 Fault supply air temperature sensor
open
The sensor or the cabling has an
interruption.
222 Fault fresh air temperature sensor short
circuit
The sensor or the cabling has a short
circuit.
The system operates at a fresh air temper-
ature of 0 °C.
Rectify fault.
Reset alarm.
223 Fault fresh air temperature sensor
interruption
The sensor or the cabling has an
interruption.
232 Fault return temperature sensor
shortcut
The sensor or the cabling has a short
circuit.
The unit continues to operate with a return
temperature of 99 °C. Functions controlled
using this sensor are not active.
Rectify fault.
Reset alarm.
233 Fault return temperature sensor open The sensor or the cabling has an
interruption.
234 Fault room temperature sensor 1
shortcut
The sensor or the cabling has a short
circuit.
– If there is only 1 sensor present:
All units in the zone switch to L_REC mode
and operate without room temperature.
– If there are several sensors:
The defective sensor is masked out. All
units in the zone use the value of the other
sensors.
Rectify fault.
Reset alarm.
235 Fault room temperature sensor 1 open The sensor or the cabling has an
interruption.
236 Fault room temperature sensor 2
shortcut
The sensor or the cabling has a short
circuit.
The defective sensor is masked out. All
units in the zone use the value of the other
sensors.
Rectify fault.
Reset alarm.
237 Fault room temperature sensor 2 open The sensor or the cabling has an
interruption.
238 Fault room temperature sensor 3
shortcut
The sensor or the cabling has a short
circuit.
239 Fault room temperature sensor 3 open The sensor or the cabling has an
interruption.
240 Fault room temperature sensor 4
shortcut
The sensor or the cabling has a short
circuit.
241 Fault room temperature sensor 4 open The sensor or the cabling has an
interruption.
287 Fault heating pump
The pump has a fault or the corre-
sponding circuit breaker has tripped.
At cold outside temperatures, the unit
switches to L_REC operating mode.
Rectify fault.
288 Fault cooling pump
The pump has a fault or the corre-
sponding circuit breaker has tripped.
The unit continues to run without cooling. Rectify fault.
289 Fault heat generation
Fault heat supply
At cold outside temperatures, all units in
the zone switch to REC operating mode.
Rectify fault.
21
TopTronic
®
C
System control for TopVent
®
Alarms
4 216 689-en-01
