User Instructions for GECO GH21RA controller
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Page 9 Edition I
19.06.2013
5.5.
Alarm/Note mode
Alarm
- The controller goes into alarm mode when one of the required sensors fails or is
disconnected, or when the cable is broken. The controller will signal that the sensor in
question is required. When the fault is repaired, the controller returns to the mode it was in
before. The controller will not enter alarm mode when the sensor fault has been repaired. Any
changes to components should be done with the controller turned off.
Note
- The controller switches to warning mode when the DHW/returning sensor fails or is
disconnected, or when the cable is broken. The controller then gives information about the
warning, and the types of operations conditionally possible without the sensor. The user must
always accept operations that are conditional on the lack of sensor, each time the controller is
restarted. This applies only to those sensors which do not affect the safe operation of the
heating system. After repairing the sensor problem or removing the cause of the interference,
the controller returns to the mode in which it was previously operating. Any changes to
components should be made with the controller turned off.
The other functions of the note mode are to give information when the hot water tank has not
been disinfected, or the temperature in the feeder has not been raised. The controller exits the
notes mode when one of the notes is UW10 or UW17.
5.6.
Emergency work.
Safe mode allows the boiler to work in case of damage to the feeder and or fan TRIAC, until
servicing is possible. For the controller to operate the feeder / fan in safe mode, the correct
mode should be selected from the menu, in addition to changing the feeder/fan connection. A
detailed description is on page 39.
6.
Operating the controller
Operating the controller is described in this chapter. It includes turning it on, using the
keyboard, a working preview of the measuring system, reading text or characters on the
screen, and editing the parameters available to the user.
6.1.
Controller fascia panel