OSTBERG HERU 400-2400 S, User Manual, Page: 115 / 120

115 / 120
2018-02-13 Climatix HERU® 400-2400
Troubleshooting
HMI alarm
Fan alarm The connector between
the unit joint is
probably not
connected
Check the connectors on the extract air fan.
On some models, the fan cabling for the extract air has
a connector located next to the dividing line of the
unit. Power and signal are of different types so that
there can be no cross-connection.
IMPORTANT! Make sure there is no power to
HERU® CX before performing this action.
Switch off the external load switch and
make sure that there is no voltage in the
incoming power feed before performing
work.
•
HERU®400 CX:
Problem does not apply to this size,
as size 04 is delivered in one unit and
therefore does not have a connector
to the extract air fan
•
HERU® 800 CX:
Check the unit connection (follow the
extract
air’s fan cables).
•
HERU®1600 CX:
Check above the rotary heat
exchanger (follow the extract
air’s fan
cables).
HMI alarm
Fan alarm
The EC motors may have
triggered an alarm
Switch off the main switch for power supply to
HERU® CX. Then reset the alarm in the
HMI, see chap. 5.4.1.
HMI alarm
Fan alarm
The fuse to the fans may
have blown
Check fuse F4; reset as needed.
HMI alarm
Supply air temp. fire
alarm
(Extract air temp. fire
alarm)
The fire alarm is
configured for
temperature alarm
on supply air and
extract air. The
temperature has
now risen above the
set value and tripped
the alarm.
Check the settings on Fire alarm temp.
setpoint. Main index > Unit >
Setpoints/Settings > All settings > Fire
alarm. temp. set.
HMI alarm
Recovery alarm
Cannot reset alarm in
HMI unit
The alarm must first be reset in EMS. This is
done by breaking line voltage to HERU®
CX.
To keep in mind:
Check what type of error EMS indicates
before acknowledging the alarm, see
chap.0.
HMI alarm
Temperature alarm
- Supply air temp.
- Extract air temp.
- Outside air temp.
- Exhaust air temp.
- Frost protection
sensor temp.
E.g. Outside temp.:
82.88 °C
The temperature has
risen above the max
temperature limit.
The temperature when
the alarm was
tripped is displayed
in the alarm text.
Acknowledge the alarm and check if the
temperature of the affected sensor seems
reasonable.