Alarm list

 

 

Code Alarm text Comment Troubleshooting tips
Text Hex
1B 1 Low supply airflow Supply flow not reaching 80% of setpoint in normal mode or 95% of setpoint while calibrating VAV

1. Too high pressure in the duct system (wrong size ducts, closed diffusers, blocked intake grills, stuck dampers)

2. Dirty filters

3. Disconnected, clogged, bent pressure tubes

Troubleshooting

2B 2 Low extract air flow Extract flow not reaching 80% of setpoint in normal mode or 95% of setpoint while calibrating VAV

1. Too high pressure in the duct system (wrong size ducts, closed diffusers, blocked intake grills, stuck dampers)

2. Dirty filters

3. Disconnected, clogged, bent pressure tubes

Troubleshooting

3B 3 VAV calibration fail Both VAV sensors values are out of allowed range (3..9V)

VAV sensor not connected, broken or wrong measuring range selected.

Troubleshooting

4B 4 Change outdoor air filter Outdoor air filter impurity level reached 100%

Message can also appear after unsuccessful filter calibration

Troubleshooting

5B 5 Change extract air filter Extract air filter impurity level reached 100%

Message can also appear after unsuccessful filter calibration

Troubleshooting

6B 6 Electric heater off Heater overheat (TK70)

Thermostat 70°C

Troubleshooting

7B 7 Electric heater off Heater radiator overheat (TK60)

On the units where TRIAC’s has separate overheating thermostat 60°C on the radiator

Troubleshooting

8B 8 Electric heater off Heater(Zone1) overheat (TK70)

Additional zone with electrical heater. Thermostat 70°C

Troubleshooting

9B 9 Electric heater off Heater(Zone1) radiator overheat (TK60)

On the units where TRIAC’s has separate overheating thermostat 60°C on the radiator

Troubleshooting

10B A Electric heater off Heater(Zone2) overheat (TK70)

Additional zone with electrical heater. Thermostat 70°C

Troubleshooting

11B B Electric heater off Heater(Zone2) radiator overheat (TK60)

Additional zone with electrical heater. Thermostat 70°C

Troubleshooting

12B C High pressure on compressor  

Reached maximum allowed pressure (18 bar), by presostat (RHP Standard). Resets at 13 bar.

Troubleshooting

13B D Low pressure on compressor  

Reached minimum allowed pressure (0,5 bar), by presostat (RHP Standard). Resets at 1,5 bar

Troubleshooting

14B E Service time  

One year of continuous operation has passed

Troubleshooting

15B F Evaporator icing Heat pump evaporator icing and can’t be defrosted

After three defrost cycles, pressure drop over evaporator have not increased above limit

Troubleshooting

16B 10 Compressor failure Compressor 1

DIN 17-18 on PM board

17B 11 Compressor failure Compressor 2

Not used

18B 12 Compressor failure Compressor 3

Not used

19B 13 Compressor off Heatpump can’t start due to too low air flow

Minimum airflow needed for the heat pump to start not reached. Increase airflow setpoint

20B 14 Compressor off Heatpump can’t start due to too low air temperature

Outdoor temperature is between max. temperature allowed for heating and min. temperature allowed for cooling (default is 15 and 20C)

21B 15      
22B 16      
23B 17      
24B 18 Compressor failure Probe U3 broken or disconnected

Analog low pressure sensor (LPT1)

25B 19 Compressor failure Probe U4 broken or disconnected

Suction temperature sensor (ST1)

26B 1A Compressor failure Probe U5 broken or disconnected

Analog high pressure sensor (HPT1)

27B 1B Compressor failure Probe U6 broken or disconnected

Discharge temperature sensor (DT1)

28B 1C Compressor failure Probe U8 broken or disconnected

Phase sequence relay (circuit 2 or circuit 3)

29B 1D Compressor failure Low SH alarm circ.1

SH<4K, more than 360 s

30B 1E Compressor failure LOP alarm circuit 1

Too low condensation pressure

31B 1F Compressor failure MOP alarm circuit 1

Too high disscharge pressure

32B 20 Compressor failure Low suction temp. circuit 1

Suction temperature < -20 °C for more than 180 s, or < -25 °C

33B 21 Compressor failure High discharge press. circuit 1

Measured by analog high pressure sensor (HPT1) >33 bar, for more than 180s

34B 22 Compressor failure Low suction pressure circuit 1

Measured by analog low pressure sensor (LPT1) <4 bar, for more than 180s, or <3,3 bar

35B 23 Compressor failure Low pressure circ.1 by pressostat

Pressostat LP1 <1,7 bar (auto reset at 2,7 bar)

36B 24 Compressor failure High pressure circ.1 by pressostat

Pressostat HP1 >42 bar (auto reset at 33 bar)

37B 25   Maintenance request compressor 1 circuit 1  
38B 26   Pump down end for max time circuit 1  
39B 27 Compressor failure Error BLDC management circuit 1

Compressor can not start because of electrical limitations (voltage, current, etc.). Can also appear of compressor type or settings missmatch.

40B 28 Compressor failure High discharge temp. circuit 1

>105°C for more than 180 s, or imediately if >115°C

41B 29 Compressor failure Alarm delta pressure circuit 1

Pressure difference is <0,5 bar after 15 s since compressor start. Possible refrigerant leackage, stuck SVR or EVD, broken compressor

42B 2A Compressor failure Start failure BLDC circuit 1

Compressor can not reach specified speed during start-up. Can appear because of compressor type/settings mismatch.

43B 2B Compressor failure Envelope alarm circuit 1

Compressor was working outside envelope zone for longer than 180 s. Needed to verify in what zone compressor was running, to find possible reasons.

44B 2C Compressor failure Offline Power+ circuit 1

No communication with Carel frequency inverter. Possible reasons: no power, broken cable, wrong settings

45B 2D Compressor failure Alarm Power+ circuit 1

Alarm generated by Carel frequency inverter. Actual alarm message needed to be checked in /_hp.html screen or on the Carel control panel.

46B 2E Compressor failure Probe S1 EVD circ.2 broken or disconnected

Analog low pressure sensor (LPT2)

47B 2F Compressor failure Probe S2 EVD circ.2 broken or disconnected

Suction temperature sensor (ST2)

48B 30 Compressor failure Probe S3 EVD circ.2 broken or disconnected

Analog high pressure sensor (HPT2)

49B

31

Compressor failure Probe S4 EVD circ.2 broken or disconnected

Discharge temperature sensor (DT2)

50B 32 Compressor failure Low SH alarm circ.2

SH<4K, more than 360 s

51B 33 Compressor failure LOP alarm circuit 2

Too low condensation pressure

52B 34 Compressor failure MOP alarm circuit 2

Too high disscharge pressure

53B 35 Compressor failure ExV motor alarm circuit 2

 

54B 36 Compressor failure Low suction temp. circuit 2

Suction temperature -20 °C for more than 180 s

55B 37 Compressor failure Battery alarm EVD circuit 2  
56B 38 Compressor failure EEPROM EVD alarm circuit 2

 

57B 39 Compressor failure Firmware EVD circ.2 not ok

 

58B 3A Compressor failure Configuration error EVD circuit 2

 

59B 3B Compressor failure Offline EVD circ.2

 

60B 3C Compressor failure High discharge press. circuit 2

Measured by analog high pressure sensor (HPT2)

61B 3D Compressor failure Low suction pressure circuit 2

Measured by analog low pressure sensor (LPT2)

62B 3E Compressor failure Low pressure circ.2 by pressostat

Pressostat LP2

63B 3F Compressor failure High pressure circ.2 by pressostat

Pressostat HP2

64B 40   Maintenance request compressor 1 circuit 2 Not used
65B 41   Pump down end for max time circuit 2 Not used
66B 42   Compressor Starter overcurrent circuit 2  
67B 43 Compressor failure Mains power phases mismatched

Check voltage and phase sequence

68B 44 Compressor failure Alarm delta pressure circuit 2

Pressure difference is <0,5 bar after 15 s since compressor start. Possible refrigerant leackage, stuck SVR or EVD, broken compressor

69B 45 Compressor failure Envelope alarm circuit 2

Compressor was working outside envelope zone for longer than 360 s. Needed to verify in what zone compressor was running, to find possible reasons

70B 46 Compressor failure Probe S1 EVD circ.3 broken or disconnected

Analog low pressure sensor (LPT3)

71B 47 Compressor failure Probe S2 EVD circ.3 broken or disconnected

Suction temperature sensor (ST3)

72B 48 Compressor failure Probe S3 EVD circ.3 broken or disconnected

Analog high pressure sensor (HPT3)

73B 49 Compressor failure Probe S4 EVD circ.3 broken or disconnected

Discharge temperature sensor (DT3)

74B 4A Compressor failure Low SH alarm circ.3

SH<4K, more than 360 s

75B 4B Compressor failure LOP alarm circuit 3

Too low condensation pressure

76B 4C Compressor failure MOP alarm circuit 3

Too high disscharge pressure

77B 4D Compressor failure ExV motor alarm circuit 3

 

78B 4E Compressor failure Low suction temp. circuit 3

Suction temperature -20 °C for more than 180 s

79B 4F Compressor failure Battery alarm EVD circuit 3

 

80B 50 Compressor failure EEPROM EVD alarm circuit 3

 

81B 51 Compressor failure Firmware EVD circ.3 not ok

 

82B 52 Compressor failure Configuration error EVD circuit 3

 

83B 53 Compressor failure Offline EVD circ.3

 

84B 54 Compressor failure High discharge press. circuit 3

Measured by analog high pressure sensor (HPT2)

85B 55 Compressor failure Low suction pressure circuit 3

Measured by analog low pressure sensor (LPT2)

86B 56 Compressor failure Low pressure circ.3 by pressostat

Pressostat LP2

87B 57 Compressor failure High pressure circ.3 by pressostat

Pressostat HP2

88B 58 Compressor failure Maintenance request compressor 1 circuit 2

Not used

89B 59 Compressor failure Pump down end for max time circuit 3

Not used

90B 5A Compressor failure Compressor Starter overcurrent circuit 3

 

91B 5B Compressor failure High discharge temp. circuit 3

 

92B 5C Compressor failure Alarm delta pressure circuit 3

Pressure difference is <0,5 bar after 15 s since compressor start. Possible refrigerant leackage, stuck SVR or EVD, broken compressor

93B 5D Compressor failure Envelope alarm circuit 3

Compressor was working outside envelope zone for longer than 360 s. Needed to verify in what zone compressor was running, to find possible reasons.

94B 5E Compressor failure Carel module configuration sequence was not completed

 

127B 7F Serviso režimas I/O override or pressure lock function is active

By deleting alarm all override inputs/outputs will be restored to automatic

 
1A 80 Supply air temp. sensor failure B1 Open circuit

Incorrect/damaged wiring, faulty sensor

Troubleshooting

2A 81 B1 Short circuit

Incorrect/damaged wiring, faulty sensor

Troubleshooting

3A 82 Extract air temp. sensor failure B2 Open circuit

Incorrect/damaged wiring, faulty sensor

Troubleshooting

4A 83 B2 Short circuit

Incorrect/damaged wiring, faulty sensor

Troubleshooting

5A 84 Outdoor air temp. sensor failure B3 Open circuit

Incorrect/damaged wiring, faulty sensor

Troubleshooting

6A 85 B3 Short circuit

Incorrect/damaged wiring, faulty sensor

Troubleshooting

7A 86 Exhaust air temp. sensor failure B4 Open circuit

Incorrect/damaged wiring, faulty sensor

Troubleshooting

8A 87 B4 Short circuit

Incorrect/damaged wiring, faulty sensor

Troubleshooting

9A 88 Water temp. sensor failure B5 Open circuit

Incorrect/damaged wiring, faulty sensor

Troubleshooting

10A 89 B5 Short circuit

Incorrect/damaged wiring, faulty sensor

Troubleshooting

11A 8A Return water temp. low Bellow set alarm temperature (default +8C)

Incorrect/damaged wiring, faulty sensor, faulty heating system/control

Troubleshooting

12A 8B Internal fire alarm Supply air temp. exceeding +70C or extract air temp. exceeding +50C

Incorrect/damaged wiring, faulty sensor

Troubleshooting

13A 8C External fire alarm External fire system

Signal received from external fire system to C5 connections 6-8

Troubleshooting

14A 8D External stop External alarm input

External signal received by controller 

Troubleshooting

15A 8E Heat exchanger failure Heat exchanger efficiency is too low

1. Rotary heat exchanger not rotating (broken belt, motor, control board)

2. CF heat exchanger by-pass failure (damper stuck, broken actuator, actuator not connected)

3. Air temperature sensors measuring incorrectly, so calculated efficiency is incorrect.

4. Air leakage between extract and supply airflows (missing gaskets, not fully closed door)

Troubleshooting

16A 8F Heat exchanger icing

 

1.After three cycles of defrosting, pressure drop over exchanger has not increased above critical limit

2.After three cycles of defrosting, exchanger efficiency has not increased above critical limit

Troubleshooting

17A 90 Low supply air temperature Supply air temp drops bellow +5C

Incorrect/damaged wiring, faulty sensor, faulty heating system/control

Troubleshooting

18A 91 High supply air temperature Supply air temp. exceeding +45C (10min)

Incorrect/damaged wiring, faulty sensor, faulty heating system/control

Troubleshooting

19A 92 Low supply air flow Supply flow not reaching 30% of setpoint

1. Disconnected, clogged, bent pressure tubes.

2. Air dampers stuck or not open

3. Fan turning in wrong direction (AC fans) 4. Wrong fan settings (k-factor, VM module microswitches, wrong max. airflow setting)

5. Control voltage not reaching the fan (broken cable, electronic board)

6. Broken fan or frequency inverter

Troubleshooting

20A 93 Low extract air flow Extract flow not reaching 30% of setpoint

1. Disconnected, clogged, bent pressure tubes.

2. Air dampers stuck or not open

3. Fan turning in wrong direction (AC fans) 4. Wrong fan settings (k-factor, VM module microswitches, wrong max. airflow setting)

5. Control voltage not reaching the fan (broken cable, electronic board)

6. Broken fan or frequency inverter

Troubleshooting

21A 94 Electric heater overheat Heater TK100

Reset electrical heating protection relay by pressing "RESET" button, check thermostat, wiring

Troubleshooting

22A 95 Heater(Zone1) TK100

Reset electrical heating protection relay by pressing "RESET" button, check thermostat, wiring

Troubleshooting

23A 96 Heater(Zone2) TK100

Reset electrical heating protection relay by pressing "RESET" button, check thermostat, wiring

Troubleshooting

24A 97 Evaporator air temp. sensor failure

B11 Open circuit

Incorrect/damaged wiring, faulty sensor

Troubleshooting

25A 98

B11 Short circuit

Incorrect/damaged wiring, faulty sensor

Troubleshooting

26A 99 Evaporator coil temp. sensor failure

B12 Open circuit

Incorrect/damaged wiring, faulty sensor

Troubleshooting

27A 9A

B12 Short circuit

Incorrect/damaged wiring, faulty sensor

Troubleshooting

28A 9B Compressor failure

Compressor 1

 

29A 9C

Compressor 2

 

30A 9D

Compressor 3

 

31A 9E Supply air temp. sensor failure

Open circuit (Zone1)

Incorrect/damaged wiring, faulty sensor

Troubleshooting

32A 9F

Short circuit (Zone1)

Incorrect/damaged wiring, faulty sensor

Troubleshooting

33A A0

Open circuit (Zone2)

Incorrect/damaged wiring, faulty sensor

Troubleshooting

34A A1

Short circuit (Zone2)

Incorrect/damaged wiring, faulty sensor

Troubleshooting

35A A2 Water temp. sensor failure

Open circuit (Zone1)

Incorrect/damaged wiring, faulty sensor

Troubleshooting

36A A3

Short circuit (Zone1)

Incorrect/damaged wiring, faulty sensor

Troubleshooting

37A A4

Open circuit (Zone2)

Incorrect/damaged wiring, faulty sensor

Troubleshooting

38A A5

Short circuit (Zone2)

Incorrect/damaged wiring, faulty sensor

Troubleshooting

39A A6 Return water temp. low

Zone1

Incorrect/damaged wiring, faulty sensor, faulty heating system/control

Troubleshooting

40A A7

Zone2

Incorrect/damaged wiring, faulty sensor, faulty heating system/control

Troubleshooting

41A A8 Supply air temp. sensor failure

B14 Open circuit

Incorrect/damaged wiring, faulty sensor

Troubleshooting

42A A9

B14 Short circuit

Incorrect/damaged wiring, faulty sensor

Troubleshooting

43A AA External stop

Zone1

 

44A AB

Zone2

 

89A D8 Communication error Carel module not responding to modbus requests

No communication with Carel main board. Possible reasons: no power, broken cable, wrong settings

Troubleshooting 

90A D9 Service mode C5 board is locked Can be unlocked only by Komfovent service department connected to the AHU.
91A DA Controller failure Too low 24V supply voltage Main power supply voltage, main controller
92A DB Too high 24V supply voltage Main power supply voltage, main controller
93A DC Supply fan C5_VM module Incorrect wiring, settings, faulty module
94A DD Exhaust fan C5_VM module Incorrect wiring, settings, faulty module
95A DE El. Heater C5_PM module Incorrect wiring, settings, faulty module
96A DF Heat pump C5_PM module Incorrect wiring, settings, faulty module
97A E0 Zone1 C5_PM module Incorrect wiring, settings, faulty module
98A E1 Zone2 C5_PM module Incorrect wiring, settings, faulty module
99A E2 Supply fan drive failure   Alarm generated by fan frequency inverter
100A E3 Supply fan drive overload (Lenze: F_AF) Alarm generated by fan frequency inverter
101A E4 Supply fan motor failure (Lenze: F_rF, F_OF1)

Alarm generated by fan frequency inverter

Troubleshooting

102A E5 Supply fan motor overload (Lenze: F_EF), Overheat Alarm generated by fan frequency inverter
103A E6 (Lenze: F_PF, F_OF), Overcurrent Alarm generated by fan frequency inverter
104A E7 Exhaust fan drive failure   Alarm generated by fan frequency inverter
105A E8 Exhaust fan drive oveload (Lenze: F_AF) Alarm generated by fan frequency inverter
106A E9 Exhaust fan motor failure (Lenze: F_rF, F_OF1)

Alarm generated by fan frequency inverter

Troubleshooting

107A EA Exhaust fan motor overload (Lenze: F_EF), Overheat Alarm generated by fan frequency inverter
108A EB (Lenze: F_PF, F_OF), Overcurrent Alarm generated by fan frequency inverter
109A EC Rotor drive failure   Alarm generated by fan frequency inverter
110A ED Rotor drive overload   Alarm generated by fan frequency inverter
111A EE Rotor motor failure   Alarm generated by fan frequency inverter
112A EF Rotor motor overload   Alarm generated by fan frequency inverter
113A F0   Alarm generated by fan frequency inverter
114A F1 Communication error Supply fan C5_VM module  Cable, settings or electronics fault
115A F2 Exhaust fan C5_VM module  Cable, settings or electronics fault
116A F3 El. Heater C5_PM module  Cable, settings or electronics fault
117A F4 Heat pump C5_PM module  Cable, settings or electronics fault
118A F5 Zone1 C5_PM module Cable, settings or electronics fault
119A F6 Zone2 C5_PM module  Cable, settings or electronics fault
120A F7 Supply drive (Lenze modbus)  Cable, settings or electronics fault
121A F8 Exhaust drive (Lenze modbus) Cable, settings or electronics fault
122A F9 Supply drive2 (Lenze modbus)  Cable, settings or electronics fault
123A FA Exhaust drive2 (Lenze modbus)  Cable, settings or electronics fault
124A FB Rotor drive Cable, settings or electronics fault
125A FC Controller failure Internal pressure sensors (C5_DP)  
126A FD C5 Analog circuit (auto-calibration, multiplexer)  Short circuit on the C5 board external terminals (incorrect wiring, broken external components)
127A FE C5 Digital circuit (EEPROM, flash)  

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