Alarm list
May be due toDescriptionAlarm text on the displayAlarm
• Open circuit or short circuit on sensor input
• Sensor does not work (see section "Disturb-
ances in comfort")
• Defective control board AA23 in F2050
Sensor fault, Sensor incoming water in F2050
(BT3).
Sensor fault BT33
• Open circuit or short circuit on sensor input
• Sensor does not work (see section "Disturb-
ances in comfort")
• Defective control board AA23 in F2050
Sensor fault, Sensor outgoing water in F2050
(BT12).
Sensor fault BT1212
• Open circuit or short circuit on sensor input
• Sensor does not work (see section "Disturb-
ances in comfort")
• Defective control board AA23 in F2050
Sensor fault, Sensor fluid pipe in F2050 (BT15).Sensor fault BT1515
• Low flow during heating operation
• Too high set temperatures
Too high temperature out from the condenser.
Self-resetting.
High condenser out162
• Temperature generated by another heat
source
Too high temperature into the condenser. Self-
resetting.
High condenser in163
• Set when the heat pump runs the defrosting
procedure
not an alarm, but an operating status instead.Defrosting in progress183
• Insufficient air circulation or blocked heat
exchanger
• Open circuit or short circuit on input for high
pressure switch (63H1)
• Defective high pressure switch
• Expansion valve not connected correctly
• Service valve closed
• Defective control board in F2050
• Low or no flow during heating operation
• Defective circulation pump
• Defective fuse, F(4A)
The high pressure switch (63H1) deployed 5
times within 60 minutes or for 60 minutes con-
tinuously.
HP alarm220
• Open circuit or short circuit on input for low
pressure sensor
• Defective low pressure sensor
• Defective control board in F2050
• Open circuit or short circuit on input for suc-
tion gas sensor (Tho-S)
• Defective suction gas sensor (Tho-S)
Too low value on the low pressure sensor 3
times within 60 minutes.
LP alarm221
• Any circuit breakers for F2050 off
• Incorrect cable routing
Communication between the control board and
the communication board is interrupted. There
must be 22 volt direct current (DC) at the switch
CNW2 on the control board (PWB1).
OU Com. error223
• The fan cannot rotate freely
• Defective control board in F2050
• Defective fan motor
• Control board in F2050 dirty
• Fuse (F2) blown
Deviations in the fan speed in F2050.Fan alarm224
• Sensor does not work (see section "Ambient
temperature sensor")
• Insufficient air circulation or heat exchanger
• Blocked
• If the fault persists during cooling, there may
be an insufficient amount of refrigerant.
• Defective control board in F2050
Temperature deviation on the hot gas sensor
(Tho-D) twice within 60 minutes or for 60
minutes continuously.
Continuously high hot gas230
• F2050 not powered
• Fault in the communication cable.
Communication fault with accessory boardCommunication error254
• Sensor does not work (see section "Disturb-
ances in comfort")
• Insufficient air circulation or blocked heat
exchanger
• Defective control board in F2050
• Too much refrigerant
Temperature deviation on the heat exchanger
sensor (Tho-R1/R2) five times within 60 minutes
or for 60 minutes continuously.
High temperature in heat ex-
changer
261
• Can occur when 15V power supply to the in-
verter PCB is unstable.
When IPM (Intelligent power module) displays
FO-signal (Fault Output) five times during a 60-
minute period.
Power transistor too hot262
• Incoming power supply interference
• Service valve closed
• Insufficient amount of refrigerant
• Compressor fault
• Defective circuit board for inverter in F2050
Voltage from the inverter outside the paramet-
ers four times within 30 minutes.
Inverter error263
• Open circuit in connection between boards
• Defective circuit board for inverter in F2050
• Defective control board in F2050
Communication between circuit board for invert-
er and control board broken.
Inverter error264
NIBE F2050Chapter 10 | Disturbances in comfort38
To Next Page
Loading...
