Alpha Alpha CB24, Инструкции по установке и обслуживанию, Страница: 16 / 36

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5.3 TEST FOR GAS SOUNDNESS AND PURGE THE SUPPLY
1. With the boiler gas service cock closed (slot at right angles to valve). Pressure test the gas supply and inlet pipework
connection to the boiler gas service cock for soundness in accordance with BS 6891.
2. Loosen the gas inlet pressure test point screw on the gas valve (see Fig. 17). Ensure the gas supply is on and open the
boiler service cock to purge in accordance with BS 6891.
3. Retighten the test point screw and test for gas soundness. Close the boiler gas service cock.
5.4 INITIAL LIGHTING - Refer to Fig. 16
1. Ensure that the gas and electrical supplies to the boiler are off and that the mains water inlet valve and the central heating
flow and return valves are open.
2. Turn on the gas and electrical supplies to the boiler.
3. Ensure all external controls are calling for heat. If the optional Clock is fitted, refer to the User's instructions, set the time
and ensure the Clock is in an 'on' mode.
4. Set the hot water and central heating temperature selectors to maximum.
5. Set the selector switch to (DHW only).
6. Open a hot water tap, the main burner will light and the boiler will provide hot water. Close the tap and the burner will go out.
7. Set the selector switch to (CH and DHW). The boiler will now run in the central heating mode. The pump will start,
the fan will start; once the pressure switch is proved, the main gas valve solenoid will open allowing the main burner to
light from the ignition electrodes.
5.5 CHECK THE BURNER PRESSURES - Fig. 17
Turn the boiler off. Loosen the burner pressure test point screw on the
gas valve and connect a pressure gauge. Allow the boiler to run for 10
minutes and check the burner pressures.
Hot water mode
1. Set the selector switch to (DHW only) and fully open a hot water tap.
2. The burner will light at the ignition rate and the burner pressure will
increase to maximum.
3. Gradually close the hot tap and check that the burner pressure
decreases to its minimum. Fully open the tap and check that the
burner pressure increases. Close the tap and check that the burner
goes off.
Note: The burner pressure settings have been factory set and do not
require adjusting. If incorrect, check that the inlet gas pressure is 20 mbar.
If the inlet gas pressure is not 20 mbar, either the pipework is too small
or the gas supply to the house is insufficient, in which case contact your gas supplier.
Central heating mode
1. Set the selector switch to (DHW and CH).
2. The burner will light at the ignition rate and will increase to the factory pre-set maximum output after 1 minute.
3. Turn off the boiler. Disconnect the pressure gauge and tighten the test point screw.
Test for gas soundness using suitable leak detection fluid.
Note: Refer to Technical Data, section 2.1 for burner pressure settings.
5.6 FINAL COMMISSIONING
1. Allow the heating system to heat up, then balance the system to achieve the necessary temperature difference across the
heating flow and return pipes at the boiler and check the system volume and pressure. (Refer to Technical Data, sections
2.2 and 2.8).
2. Turn off the boiler.
3. Thoroughly flush out the water pipework and with no pressure in the boiler heating circuit, empty the cyclone at it's drain point
(see Fig. 11) of any debris. Clean the mains water inlet filter (see Fig. 11).
4. Re-pressurise the system as described in section 5.1.
5.7 FINAL ASSEMBLY
1. Raise the control panel and secure in position with the screws provided.
2. If the boiler is to be left in service with the User, set the controls, clock (if fitted, see User's Operating manual) and room
thermostat (if fitted) to the User's requirements.
Alpha CB24/28 - Commissioning
Fig. 17