Geco GH21RA User manual

INSTRUCTIONS
FOR CONTROLLER
GH21RA
FOR CENTRAL
HEATING BOILER
CONTROLLER
WITH FEEDER
SCREW
USER MANUAL
We strongly recommend that you familiarise yourself fully with the contents of this manual
before installing and using any of our devices. If you have any questions, please contact us
between 08:00 and 16:00

User Instructions for GECO GH21RA controller
______________________________________________________________________________
Page 2 Edition I 19.06.2013
Table of contents
1. DESCRIPTION OF CONTROLLER ..........................................................................................................................3
2. TECHNICAL SPECIFICATIONS...............................................................................................................................3
3. REQUIRE ENTS FOR ELECTRICAL INSTALLATION.........................................................................................4
5. CONTROLLER ODES............................................................................................................................................6
5.1. S TANDBY ODE .................................................................................................................................................7
5.2. A UTO ATIC ODE - HEATING .............................................................................................................................7
5.3. A UTO ATIC ODE - AINTAIN ...........................................................................................................................8
5.4. ANUAL ODE ..................................................................................................................................................8
5.5. A LAR /N OTE ODE ..........................................................................................................................................9
5.6. E ERGENCY WORK ............................................................................................................................................9
6. OPERATING THE CONTROLLER...........................................................................................................................9
6.1. C ONTROLLER FASCIA PANEL ...............................................................................................................................9
6.2. O PERATING THE CONTROLLER – AIN SCREEN ..................................................................................................11
6.3. P REVIEW OF SYSTE OPERATIONS ....................................................................................................................11
6.4. H ELP BUTTON ..................................................................................................................................................12
6.5. ANUAL ODE ................................................................................................................................................13
6.6. C ONTROLLER ENU – G RAPHIC TREE ................................................................................................................14
6.6.1 U SER SETTINGS ................................................................................................................................................15
6.6.2 I NSTALLATION SETTINGS ..................................................................................................................................16
6.6.3 O PERATION HISTORY .......................................................................................................................................17
6.6.4 C ONTROL PANEL SETTINGS ...............................................................................................................................19
7. DESCRIPTION OF ADDITIONAL FUNCTIONS ...................................................................................................20
7.1. DHW PRIORITY ( HOT WATER )........................................................................................................................20
7.2. S U ER FUNCTION ..........................................................................................................................................20
7.3. A NTI - LEGIONELLA FUNCTION ............................................................................................................................21
7.4. GA03HA ROO PANEL ....................................................................................................................................22
7.5. F UEL FEEDER TE PERATURE DETECTION ..........................................................................................................23
7.6. B OILER EXTINGUISHED DETECTION ...................................................................................................................24
7.7. A NTI -S TOP FUNCTION ......................................................................................................................................24
7.8. G RATE ODE ...................................................................................................................................................24
7.9. P U P ONLY ODE ............................................................................................................................................25
7.10. O PERATION RECORD ........................................................................................................................................25
7.11. E ERGENCY WORK ..........................................................................................................................................25
8. SYSTE INSTALLATION......................................................................................................................................26
8.1 H EATING INSTALLATION NU BER 1..................................................................................................................26
8.2 H EATING INSTALLATION NU BER 2..................................................................................................................27
8.3 H EATING INSTALLATION NU BER 3..................................................................................................................28
9. CONTROLLER ALGORITH S FOR ATTACHED DEVICES ................................................................................29
9.1 HEATING ODE – FUEL FEEDER .............................................................................................................29
9.2 AUTO ATIC ODE – CH PU PS .............................................................................................................29
9.3 HEATING ODE - FAN ...............................................................................................................................29
9.4 AUTO ATIC ODE – DHW/ IXER PU P.............................................................................................30
9.5 AINTAIN ODE – FAN AND FEEDER....................................................................................................30
10. ALAR S .................................................................................................................................................................31
11. E ERGENCY WORK..............................................................................................................................................37
12. TE PERATURE LI ITER (STB). ...................................................................................................................38
13. LOSS OF POWER ..............................................................................................................................................39
14. GH03HA ROO PANEL ...................................................................................................................................39
15. IN CASE OF DA AGE TO THE CONTROLLER...............................................................................................41
17. INFOR ATION REGARDING THE LABELING AND DISPOSAL OF WASTE ELECTRONIC AND
ELECTRICAL EQUIP ENT ............................................................................................................................................43

User Instructions for GECO GH21RA controller
______________________________________________________________________________
Page 3 Edition I 19.06.2013
1. Description of controller
The GH21RA controller is assembled using microprocessor techni ues utilising automatic
surface mounting.
This controller is a device used to control the process of preparing domestic hot water
(the DHW circuit), and provides support for the main circuit (circuit CH). Parameters can be
adapted according to the condition and the type of boiler.
The controller is e uipped with a system to guard against power failure and various types of
interference. The controller identifies each emergency and gives a visual and audio warning.
The controller automatically supports three installation configurations, which meet the
re uirements of the installer fully. The device supports three temperature sensor inputs,
digital input for reed relay switch, additional output for room panel GA03HA, and four outputs
for external devices.
The GH21RA controller is e uipped with:
• Temperature inputs:
- to measure the temperature of the water coming from the boiler
- to measure the temperature of the feeder tray
- to measure the temperature of the water in the boiler / returning CH temperature
•Digital input
- for connecting cotter pin break sensor to boiler feeder screw – reed relay
• Input (RS485)
- Dedicated connector for GECO GA03HA room panel
2. Technical specifications
Supply voltage 230V
~ +10% -15%
Resistance
characteristics of NTC
sensor
Operating temperature od +5°C do +40°C
Humidity od 20% do 80% RH
Temp.
°C
Re
sistance
Ω
Fuse – Fan, Feeder 3.15A 0 7174.89
Sensor type NTC 2.2k
Ω
10 4374.83
Sensor temperature
operating range NTC: 0°C÷100°C 20 2747.10
30 1774.91
40 1172.09
Input Maximum continuous
load 50 795.08
60 547.95
CWU pump 1A 250W 70 384.62
CO pump 1A 250W 80 275.86
Fan* 1A 250W 90 202.37
Feeder* 1A 250W 100 149.16

User Instructions for GECO GH21RA controller
______________________________________________________________________________
Page 4 Edition I 19.06.2013
*When a contactor or relay proxy is connected, use a dedicated blowout
system (eg varistor). Omission of this security measure may result in
malfunction or damage to the controller output.
3. Requirements for electrical installation
WARNING!
Only a person with a valid licence to carry out electrical installation work can install the controller
wiring and connection technologies. It is recommended that the work is carried out by a qualified
installation engineer. The following are the basic requirements for the electrical power supply for
this particular controller:
1. Repairs, maintenance and other work on the system can be carried out only after
disconnecting the main power supply.
2. The room in which the controller is to be installed should be equipped with 230V/50Hz
electrical system in accordance with the applicable regulations.
3. The controller should be supplied from a dedicated circuit 230VAC/50Hz grid, protected by
a circuit breaker.
4. The controller power cable should have a cross section minimum mechanical strength of 2.5
[mm2]
5. The cable must be protected from mechanical damage, by keeping it in a duct or housing
4. Graphic and text descriptions of driver connections
When the cable has been prepared, you will be ready to connect the power to the controller and
temperature sensors, thermostats and other devices:
•The 230 V power supply should be connected to the controller using the terminals marked “L”
and “N” – in inputs 01-02.
•The NTC temperature sensor must be connected to the inputs in accordance with the
instructions set out in the tables in section 8, System Installation. Please note that the number of
sensors supported depends on the type of installation, and unused sensors do not have to be
connected to inputs.
•The room panel GA03HA must be connected to a separate input, as described.
•Technological equipment (pumps / fans / feeder) should be connected to the outputs, as
described in the tables in section 8, System Installation and according to the selected installation

User Instructions for GECO GH21RA controller
______________________________________________________________________________
Page 5 Edition I 19.06.2013
Input parameters are described in the following tables:
Description of controller inputs – temperature sensors
Temperature sensor Type of input Controller designation
Water flowing from
the boiler NTC 50-51
Water in the DHW
boiler/ Return temp. NTC 52-53
Fuel feeder NTC 54-55
Description of controller inputs – room thermostat GA03HA
Type of room
thermostat Type of input Controller designation
GH21RA dedicated
room panel - GECO RS485 58-59-60-61
Description of controller inputs – digital
Cotter pin break
sensor for feeder Type of input Controller designation
Reed relay CTC100 56-57
Description of controller outputs – technological equipment
Device installed Type of input Controller designation
CH pump Relay 05-06
DHW pump Relay 07-08
Feeder TRIAC 09-11
Fan TRIAC 12-14

User Instructions for GECO GH21RA controller
______________________________________________________________________________
Page 6 Edition I 19.06.2013
ONLY A QUALIFIED WIRING TECHNICIAN MAY
CONNECT DEVICES TO THE GH21RA CONTROLLER.
5. Controller modes
The controller can be operated in five modes:
•Standby – returns the controller to the state before loss of power. The controller
algorithm is not implemented, the clock operates in real time, and the chosen installation
settings are stored.
•Automatic - There are two sub-modes, heating and maintain
Heating – in this mode, the algorithm is implemented in the control mode selected
depending on the type of fuel
Maintain - the controller enters this mode if the boiler temperature reaches the set point.
In this mode, an individually prepared algorithm is implemented.
•anual – This mode is used only to validate the on / off (tests) for each installation of
technological e uipment, so when you are sure that tests are finished, go to the automatic
mode.
•Alarm – Characterised by the occurrence of an alarm that prevents further operation of
the e uipment or the occurrence of a warning, which allows the user to accept temporary
operation under warning conditions accepted by the user with the awareness that it is
temporary in nature. When the fault is resolved, the driver returns to the mode it was in
before.
•Emergency work – Emergency work allows the boiler to work in case of damage to the
feeder and or fan TRIAC, until servicing is possible.

User Instructions for GECO GH21RA controller
______________________________________________________________________________
Page 7 Edition I 19.06.2013
5.1. Standby mode
After the installation procedure described in the previous chapter, the GH21RA driver
is turned on standby. In this mode, the screen displays a message about how to select
automatic or manual mode.
When the controller is in standby mode, you can switch to manual mode using the
button . During normal operation, it is possible to return the controller to standby mode
at any time, by pressing the button .
In standby mode, all outputs and the alarm sound signal are disabled. When the controller is
switched to automatic mode, the display shows the actual temperature of the water in the
boiler, the set temperature, and information about the controller mode.
5.2. Automatic mode - heating
In automatic mode, the controller implements the control algorithm for the chosen heating
schema, according to the heating regulation option chosen. Basic information about the
system, displayed on the main screen, includes current and set boiler temperature, and
operating mode. The user may choose from three heating regulation options: Standard, grate
mode and pump only.
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.

User Instructions for GECO GH21RA controller
______________________________________________________________________________
Page 8 Edition I 19.06.2013
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:
aintain – when the standard option is set
Grate mode – when grate mode is set
A detailed description of non-standard heating regulation options can be found in section 7.
5.4. anual 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 e uipment. 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 e uipment will be operated by the controller.
After entering the manual mode, operation of all e uipment will be stopped automatically.
The controller working in automatic mode displays text information at the top of the screen –
‘manual mode’.

User Instructions for GECO GH21RA controller
______________________________________________________________________________
Page 9 Edition I 19.06.2013
5.5. Alarm/Note mode
Alarm - The controller goes into alarm mode when one of the re uired sensors fails or is
disconnected, or when the cable is broken. The controller will signal that the sensor in
uestion is re uired. 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

User Instructions for GECO GH21RA controller
______________________________________________________________________________
Page 10 Edition I 19.06.2013
Button Description Function
Turn on/off The main screen appears
Change modes
Switch between manual and automatic
In the ‘boiler mode bar’, Manual Mode
appears, or in the case of Automatic
Mode, the display reads Heating,
Grate Mode H, Pump only, Maintain,
or Grate mode M
Automatic mode allows a view of
devices, temperature and accompanying
features. In manual mode, view
temperature and accompanying
features, and see devices which can be
edited.
The screen shows temperature,
devices and accompanying features
From the main screen, go to the user
help menu.
From the alarm and note screen, go to
Data service
The screen shows help for users.
The screen shows product
information and service helpline
information.
Confirm change.
Enter Menu from the main screen
Saves change
Goes to Menu from the main screen
Exit without confirming changes.
Hold the button for three seconds to go
to the main screen
Exit to previous screen or higher level
menu
Right arrow
Quickly go to boiler output temperature
screen from the main screen.
Move to the next column or row on
the right.
The screen displays boiler output
temperature.
Left arrow
Quickly go to boiler output temperature
screen from the main screen.
Move to the next column or row on
the left.
The screen displays boiler output
temperature.
Up arrow
Increase value
Go to the next position above
Increase the value by one step
Down arrow
Decrease value
Go to the next position below
Decrease the value by one step

User Instructions for GECO GH21RA controller
______________________________________________________________________________
Page 11 Edition I 19.06.2013
6.2. Operating the controller – main screen
When first connected to a power source, the controller turns on in standby mode. The
function button is used to turn the controller on/off, and to move from standby to
manual mode.
⇒
6.3. Preview of system operations
The controller offers a uick preview of system operations. When you press the button
in any mode, you can preview all the major parameters of the controller, ie temperature
measured by the controller, device status, and active / inactive control functions.
All information on the work of the heating system are divided into categories and placed on
separate screens. Move between the screens by using the buttons .
In this place shows
controller working
just in safe mode
Directional
keys, for
changing
values
Left side of the display
is changeable by user
in controller settings.
User choose with one
of the parameters will
by show.
Set boiler
temperature
Boiler mode
HEATING
MAINTAIN
MANUAL MODE
GRATE MODE H
ONLY PUMP
GRATE MODE M
Current boiler
temperature

User Instructions for GECO GH21RA controller
______________________________________________________________________________
Page 12 Edition I 19.06.2013
At the bottom of every screen there is a text description of the item. Move between items on
the screen using the buttons .
The curser shows the position on the screen. The current device is shown by the negation
of the icon corresponding to the device. Current additional functions are shown in the same
way. System temperature preview is possible in all controller modes. In the manual mode, it is
also possible to switch devices on and off.
6.4. Help button
Using the button from the main screen opens the help menu, from where the user can
get service information and descriptions of all icons displayed on the controller’s screens.

User Instructions for GECO GH21RA controller
______________________________________________________________________________
Page 13 Edition I 19.06.2013
Basic information about the boiler and controller manufacturer is available:
USING THE BUTTON FROM ALARM MODE TAKES YOU TO
SERVICE INFORMATION. THE FOLLOWING IS DISPLAYED ON THE
SCREEN: CONTROLLER MODEL, PROGRAMME NUMBER, AND
TELEPHONE CONTACT DETAILS FOR THE MANUFACTURER OR
TECHNICIAN.
6.5. anual mode
Pressing the button in automatic mode switches the controller to manual mode, and
immediately stops all devices.
In this mode, the user can manually turn on/off the fan, feeder, heating pump and hot water
pump, independently of each other. To do this, press the button which will open the
screen for editing the devices.
After moving to the desired position on the screen, according to the information text at
the bottom, using the button will switch on and off the selected device. The cursor shows
the position on the screen. The device to be switched on or off is indicated by a backlit icon.

User Instructions for GECO GH21RA controller
______________________________________________________________________________
Page 14 Edition I 19.06.2013
MENU
Operation record
User settings
Boiler temperature
Temperature
DHW
/
Return
Fan speed
Feeder working time
Installation settings
Configuration layout
Domestic Hot Water
(optional)
Summer mode
(optional)
Feeder stop time
Control panel settings
4
Language selection
Date and time
Anti-Legionella
(optional)
Maintain time
Alarms and notes
Boiler operating time
Emergency work time
Exceeding maximum
temperature
Display selection
Standard
Profile 1
Control mode
Standard control
Fire grate mode
Anti-stop function
Standard
Full
Off
Emergency work
Inactive
Power supply outage
Pump only
Feeder
Fan
Factory settings
Boiler temperature
hysteresis
DHW temperature
hysteresis (optional
)
Feeder + Fan
6.6. Controller menu – Graphic tree

User Instructions for GECO GH21RA controller
______________________________________________________________________________
Page 15 Edition I 19.06.2013
6.6.1 User settings
Description of user settings parameters in ax
Factory
settings
Set boiler temperature 'S3' 'S4' 50°C
Set DHW/returning temperature (optional) 35 65 40°C
Fan speed 1 10 5
Feeder working time 2 250 15s
Feeder stop time 5 250 45s
Maintain time 1 250 15min
•Set boiler temperature – Temperature that the boiler will reach
•Set DHW/returning temperature – Temperature to which the boiler will rise. This
parameter is available for users only when the DHW (temp DHW)/additional mixer pump
(temp returning) option is selected.
•Fan speed – This parameter sets the fan speed, i.e., the amount of air supplied. It allows the
selection of fan speed depending on the uality and type of fuel used.
•Feeder work time – This parameter describes the length of time that the fuel feeder is
connected in HEAT mode, in standard setting
•Feeder stop time – This is the interval between each supply of fuel to the boiler in AUTO
mode. The range varies from 5 s to 250 s.
•aintain time – The time after which the controller switches on the fan and feeder,
specified by the manufacturer to prevent the boiler shutting down in maintain mode. The
range is from 5 min to 250 min.

User Instructions for GECO GH21RA controller
______________________________________________________________________________
Page 16 Edition I 19.06.2013
6.6.2 Installation settings
Description of installation parameters in ax
Factory
settings
System configurations:
(1) - K1: Boiler + CH
(2) - K2: Boiler + CH + DHW
(3) - K3: Boiler + CH + Mixer
1 3 1
DHW priority (optional) No Yes No
Summer mode (optional) No Yes No
Anti-Legionella (optional) No Yes No
Boiler temperature hysteresis 2 10 5°C
Temperature hysteresis of DHW/returning (optional) 2 10 5°C
Regulation option:
(1) - Standard
(2) – Grate mode
(3) – Pump only
1 3 1
Anti-stop function:
(1) - Standard
(2) - Complete
(3) - Inactive
1 3 3
Emergency work:
(1) - Inactive
(2) - Feeder
(3) – Fan
(4) – Feeder + Fan
1 3 1
•System configuration – Allows selection of the heating system operated by the controller,
with an additional pump or without. A description of the system is in section 8.
•DHW priority – Activating the function makes water heating the primary function of the
Controller. A description of the functions in section 7.
•Summer mode – This function turns off the central heating pump and the boiler operates
only to heat water. A description of this function is in section 7.
•Anti-legionella – This is aimed at limiting the growth of bacteria of the genus legionella
pneumophila in the hot water. A description of this function is in section 7.
•Boiler temperature hysteresis – value of the boiler temperature hysteresis, at which
maintain mode is exited and heat mode is resumed.
•DHW temperature hysteresis – value of DHW temperature hysteresis, at which the pump
returns to hot water mode, or exits maintain mode.

User Instructions for GECO GH21RA controller
______________________________________________________________________________
Page 17 Edition I 19.06.2013
•Regulation option – Allows customisation of the system operation algorithm according to
type of fuel and technical capabilities. A description of this function is in section 7.
•Anti-stop function – Allows a security function for connected devices, which guards
against system deterioration during the summer months. A description of this function is in
section 7.
•Emergency work –Safe mode allows the boiler to work in case of damage to the feeder and
or fan TRIAC, until servicing is possible. A description of this function is in section 7.
6.6.3 Operation history
Operation history is where information on all controller malfunctions and custom activities
is stored. All failures and irregularities identified by the programme are stored and archived
according to whether they are alarms or notes.
Operation history menu:
Additional information is stored to help the user or service technician identify any
irregularities in system operation. The types of events recorded in operation history are:
Alarms and notes – The controller can store the last 8 alarm conditions detected. Alarms
and comments are displayed in a chronological list, with the most recent at the top. Alarms
are indicated with the symbol AL, and notes with UW, along with information about the type
of problem and the date and precise time at which it occurred.

User Instructions for GECO GH21RA controller
______________________________________________________________________________
Page 18 Edition I 19.06.2013
All new alerts appear on the operation history list alongside an envelope icon, indicating an
‘unread’ alert that needs the attention of the user or a service engineer. The envelope icon
disappears when the alert has been read.
Boiler operating time - The screen shows the operating time, in automatic heating and
maintain mode. The time is measured by the hour [h].
Emergency work time – The screen shows safe mode operating time, without breakdown of
feeder and fan, measured by the hour [h].
Exceeding maximum temperature – The screen shows the number of times the maximum
temperature of 85°C has been exceeded, displayed in number of incidences.

User Instructions for GECO GH21RA controller
______________________________________________________________________________
Page 19 Edition I 19.06.2013
Power supply outage – The screen shows the number of times that power to the controller
has failed, displayed in number of incidences.
6.6.4 Control panel settings
Settings for the controller, which do not effect heating system operations, can be found in the
controller settings panel.
Controller settings parameters:
Language selection – The controller allows the user to choose from one of several language
settings.

User Instructions for GECO GH21RA controller
______________________________________________________________________________
Page 20 Edition I 19.06.2013
Date and time – In order to ensure that all of the controller functions work correctly and at
the optimum level, set the correct time and date.
Display selection – The user can set a personal profile screen, and customise the type of
information that will be shown. The settings menu offers several choices, with ‘standard’ set by
default.
7. Description of additional functions
7.1. DHW priority (hot water)
The GH21RA controller can be set to pump hot water as a priority. If you select this mode,
water heating becomes the primary function of the controller, with heating (CH) secondary.
This is only available in the second configuration. To enable this function, set the value to
"yes" in the menu.
To enable this function, set the value to ‘YES’ in the main menu.
7.2. Summer function
The GH21RA controller is e uipped with a summer mode, which can be used in the
summer to turn off the CH pump so that the boiler only heats water. For this function to work,
a system installation supporting a DHW pump must be selected. This is only available in the
second configuration.
To enable this function, set the value to ‘YES’ in the main menu.