User Instructions for GECO GH21TA controller
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Page 8 Edition I
19.06.2013
In automatic heating mode, the controller displays text information in the top part of the
screen:
Heating
– when the standard regulation option is set
Grate mode H
– when the grate mode option is set
Pump only
– when the pump only mode is set
A detailed description of non-standard heating regulation options can be found in section 7.
5.3.
Automatic mode - maintain
The controller enters this mode if the temperature in the boiler reaches that set by the
user in the parameters menu.
The fuel feeder and fan are disabled, for the time set by the user in the ‘maintain time’
parameter. After this time, the controller turns on the feeder and fan for the time set by the
manufacturer (service parameter S20). It is usual for the fan to operate longer than the feeder
during the time set in service parameter S18, in order to ignite the fuel supplied.
The controller will exit maintain mode and return to automatic mode, if the temperature of
the boiler falls below the value set in installation parameter ‘boiler temperature hysteresis’,
which can be edited by the user. The central heating pump works in the same way as in
automatic mode.
When working in automatic mode maintain, text information is shown in the top part of the
screen:
Maintain
– when the standard option is set
Grate mode M
– when grate mode is set
A detailed description of non-standard heating regulation options can be found in section 7.
5.4.
Manual mode
In manual mode, the controller does not implement the control algorithm, and the number
and type of technological devices connected is dependent on the user, who takes
responsibility for the correct operation of the equipment. On the main screen, the actual and
set boiler temperature is always displayed. The choice of heating regulation option does not
affect the operation of the system in manual mode. In this case, the user has full control over
what equipment will be operated by the controller.
