EN
UAB KOMFOVENT we reserve the right to make changes without prior notice
C5.1-20-05
16
The function of step rotation is provided, when capacities of coolers are
the same.
The number of direct evaporation cooling units must be provided in ad-
vance.
2.7.4. Reversal of direct evaporation coolers
There is a reverse option of direct evaporation coolers, i.e. when the cooler is switched to the heating mode. In
such case, there must be only max 3 cooling control steps. There are control terminals DX3 for connection of
the cooler reversing signal “Heating” (Pic. 1.3 b.).
The option of reversal of direct evaporation cooling units must be pro-
vided in advance.
2.8. Troubleshooting
If the unit fails to operate:
• Make sure that the unit is connected to the power supply network.
• Check whether the main switch (if designed) is turned on.
• Check all fuses of the automatics. If necessary, replace blown-out fuses with new ones having the same
electrical parameters (the sizes of the fuses are indicated on the schematic electrical diagram).
• Check whether there is any failure message on the control panel. If there is indication, it needs to be elimi-
nated first. In order to eliminate the failure, follow the table.
• If nothing is indicated on the control panel, check whether cable connecting control panel with the unit is
not damaged.
2.8 Table. Alarms indicated on the control panel, their possible causes and elimination methods
Code
Message
Possible cause
Elimination
14B
Service time
If unit continuous operation (without
breaks) was 12 months, then periodic
inspection message appears.
After disconnecting the unit from power
supply, it is necessary to carry out peri-
odic inspection of the unit, i.e. to check
the condition of the heat exchanger,
the heater and fans.
1B, 19A
Low supply air flow
Too high resistance of the ventilation
system.
Check pressure pipes, air dampers, air
filters and make sure that the ventila
-
tion system is not blocked.
2B, 20A
Low extract air flow
Too high resistance of the ventilation
system.
Check pressure pipes, air dampers, air
filters and make sure that the ventilation
system is not blocked.
3B
VAV calibration fail
Pressure sensors are not connected
or broken.
Check connections of the sensor or
replace the sensor.
4B
Change outdoor air filter The fresh air filter is blocked.
Shut down the unit and replace the
filter.
5B
Change extract air filter
The extract air filter is blocked.
Shut down the unit and replace the
filter.
6B-11B
Electric heater off
The heater is disconnected due to too
low air volume.
As soon as the heater cools down,
protection resets automatically. It is
recommended to increase the ventila-
tion intensity level.
113B,114B
CF exchanger not
calibrated
CF exchanger calibration not perfor
-
med or failed
Make sure that all doors are closed,
there is no obstructions in the ducts
and AHU can reached airflow setpoint
of COMFORT 1 mode. Repeat cali
-
bration manually (see 2.5.1.3.).
127B
Service mode
Temporary mode, which can be acti-
vated by the service personnel.
The service mode is switched off by
simply deleting the alert message.
