34
14. Commissioning and Testing
(continued)
14.3 Adjusting the CO
2
Adjustment screw
Fig. 41
Q
Fig. 42
1. Remove the casing panel as described in Section 18.1
(page 45);
2. Connect a manometer to the inlet test nipple (Fig. 41) on
the gas valve, turn on the Central Heating and ensure the
inlet working pressure is 20mbar. If correct proceed as
follows;
3. Turn on the combustion analyser, remove the combustion
test point plug
Q
(Fig. 42) and insert the analyser probe
into the test point;
4. Turn on the Central Heating and ensure that the boiler is
firing.
5. Access the setting menu by pressing the and
buttons for 5 seconds the
icon will be shown in the
display;
6. Press the menu button four times to access Menu 5
and press the setting button once to switch the output
of the boiler to maximum (two digits will be flashing
indicating the temperature of the boiler). There will be a
cursor at the top of the display indicating the boiler is at
maximum output. If the cursor is at the bottom of the
display (indicating minimum output) press the button
the change to maximum output;
7. If necessary adjust the screw on the gas valve (Fig. 41) to
set the CO
2
to 8.9% +/- 0.2% (NG) or 8.9% +/- 0.2%
(LPG) with the front case removed;
8. Press the setting button once to set the combustion
control rate mode to minimum, and, if necessary, adjust
the screw on the gas valve to set the CO
2
to 9.2% +/-
0.2% (NG) or 9.7% +/- 0.2% (LPG) with the front case
removed;
9. Press the setting button again to set the combustion
rate control mode to maximum and if necessary adjust
the screw on the gas valve to set the CO
2
to 8.9% +/-
0.2% (NG) or 9.7% +/- 0.2% (LPG) with the front case
removed;
10. Reassemble in reverse order.
14.4 Gas Conversion
To convert from Natural Gas (G20) to LPG (G31), it is
necessary to insert a diaphragm between the gas valve and
air/gas arm.
Once the conversion has been made, the CO
2
setting will
need to be checked as described in Section 14.3, for LPG
the CO
2
reading should be 10% +/- 0.2% with the front case
fitted or 9.7% +/- 0.2% with the front case removed.
To convert from LPG (G31) to Natural Gas (G20), it is
necessary to remove the diaphragm and restrictor from
between the gas valve and air/gas arm.
Once the conversion has been made, the CO
2
setting will
need to be checked as described in Section 14.3, for NG the
CO
2
reading should be 9.2% +/- 0.2% with the front case
fitted or 8.9% +/- 0.2% with the front case removed.
14.6 Fitting the external sensor
14.5 Range rating the maximum heating
power
To adjust the maximum heating power it is necessary to
access the settings menu by pressing the and
buttons together for five seconds, and proceed as follows;
1. Press the menu button 3 times to access Menu 4;
2. Press the button to access Menu 4.9;
3. The value is adjustable between 0 and 10, 0 being the
minimum output and 10 being the maximum, please refer
to the chart on page 36 (Fig. 44) for the required setting;
4. The maximum central heating output can now be
adjusted by pressing the setting button
;
5. To exit the setting mode, do not press any buttons for 1
minute, the boiler will automatically exit the Setting Menu.
The external sensor should be fitted 1.5 meters above the
floor on a North to North West facing wall out of direct
sunlight.
To connect the external sensor, it is first necessary to
remove the casing panel as described in Section 18 (page
45);
Remove the PCB cover as described in Section 18.4 and
connect the external sensor as described in Section 18.5
(page 54).
has been bled from the system;
- Loosen the cap on the head of the pump to eliminate any
air pockets;
- Repeat the procedure for bleeding the radiators of air;
- Check the system pressure and, if it has dropped, open
the filling loop again to bring the pressure back up to 1.5
bar;
2. Make sure that all radiator valves are open;
3. Turn on the gas cock and check the seals on the
connections with any approved soap solution and
eliminate any leaks;
4. Press the reset button
28
(Fig. 1) the boiler will re-attempt
ignition. If the burner does not light the first time, wait 1
minute and repeat the procedure;
5. Once the boiler has ignited check the minimum and
maximum CO
2
values and gas rates;
- Adjust if necessary as indicated in Section 14.3.
Inlet test nipple
Summary of Contents for Minima HE System 24 Nat
Page 19: ...19 1 2 A A Fig 14 Fig 16 Fig 13 11 Installing the Boiler continued Fig 15 P P ...
Page 22: ...22 Fig 21 Fig 22 Fig 23 ...
Page 31: ...31 WIRING DIAGRAM FOR CONNECTION TO AN OPEN VENTED CYLINDER DIAGRAM B ...
Page 32: ...32 WIRING DIAGRAM FOR CONNECTION TO AN MTS UNVENTED CYLINDER DIAGRAM A ...
Page 61: ...61 24 Benchmark Commissioning Checklist ...
Page 62: ...62 25 Service Interval Record ...
Page 63: ...63 ...
