59
3062878_201707
14. Fault messages
Alarm messages
Effects
Cause
Remedy
Frost thermostat responded
(AL13)
Fans are switched
off; outdoor air
damper is closed;
heating circuit pump
starts; heating circuit
mixer is opened; heat
source receives a
demand
Temperature captured
at the thermostat below
limit
Check heating medium;
check heating circuit pump;
check frost stat, acknowledge
fault message
Frost prot. temp. vent. air
below set value (AL14)
Fans are switched
off; outdoor air
damper is closed;
heating circuit pump
starts; heating circuit
mixer is opened; heat
source receives a
demand. With electric
heater bank: System
off
Supply air temperature
too low
Check heating medium;
check heating circuit pump;
check parameters, acknowledge
fault message
Temperature limiter,
electric heater bank (AL15)
The system shuts
down after a delay
Electric heater bank
temperature too high
Check heater bank;
acknowledge fault message
Safety temperature limiter
elec. htr bank (AL16)
The system shuts
down after a delay
Electric heater bank
temperature too high
Check heater bank;
acknowledge fault message
Fault, pump, cold water
bank (AL17)
Pump off, cooling
valve closed, demand
chiller off
An overload relay of an
external cooling circuit
pump has responded
Reset overload relay; check
power drawn by the pump;
acknowledge fault message
Central fault ext
refrigeration unit (AL18)
Chiller is switched off Cooling unit / direct
evaporator has
recognised a fault;
cooling unit / direct
evaporator faulty
Check cooling unit / direct
evaporator; acknowledge fault
message
Fire alarm system
responded (AL19)
Subject to parameter
settings, either
system OFF, only
message or smoke
extraction
Smoke detector has
responded
Acknowledge fault message
Vent. temp sensor faulty or
not connected (AL20)
The system shuts
down
Sensor or lead faulty
Check sensor and lead,
acknowledge fault message
Vent. air hum. sensor faulty
or not connected (AL21)
Humidifier shuts
down; system
continues to operate
Sensor or lead faulty
Check sensor and lead,
acknowledge fault message
Room temp sensor faulty or
not connected (AL22)
The system shuts
down
Sensor or lead faulty
Check sensor and lead,
acknowledge fault message
Indoor air humidity sensor
faulty or not connected
(AL23)
Humidifier shuts
down; system
continues to operate
Sensor or lead faulty
Check sensor and lead,
acknowledge fault message
Extr. air temp sensor faulty
or not connected (AL24)
If an extract air /
supply air cascade
is installed:
System OFF
otherwise
message only
Sensor or lead faulty
Check sensor and lead,
acknowledge fault message
Extr. air hum. sensor faulty
or not connected (AL25)
Humidifier shuts
down; system
continues to operate
Sensor or lead faulty
Check sensor and lead,
acknowledge fault message