11. Carefully examine all seals and gaskets, replacing if necessary.
Look for any evidence of leaks or corrosion and if found determine
and rectify the cause.
12. Reassemble in reverse order.
13. Complete the relevant Service Interval Record section of the Bench
mark Commissioning Checklist at the rear of this publication and
then hand it back to the user.
9.2.2
Checking the water pressure
In order for the boiler to operate correctly, the pressure of the water in the
heating circuit must be between 1.0 and 1.5 bar. Restore the water pres
sure if necessary.
9.2.3
Checking the expansion vessel
Check the expansion vessel and recharge or replace it if necessary.
Check its pre-charge every year and restore the pressure to 1 bar if nec
essary.
9.2.4
Checking the automatic air vent
Check that the pump venting valve is working. In the event of a leak, re
place the valve.
9.2.5
Checking the burner and cleaning the heat exchanger
1. Isolate the boiler from the gas & electrical supplies.
2. Remove the front panel.
3. Remove the silencer.
4. Disconnect the spark electrode lead and earth wire from the detec
tion / spark electrode.
5. Remove the clip securing the gas feed pipe to the fan. Disconnect
the pipe.
6. Completely remove the combustion chamber / burner door assembly
by unscrewing the four M6 nuts and drawing it forwards to disen
gage it from the heat exchanger..
7. Check that the detection/spark electrode is not worn. Replace the
electrode if necessary.
8. Check the condition of the burner, the gasket and the insulation
board.
9. Any loose deposits in the heat exchanger should be removed using
a vacuum cleaner.
10. A brush with plastic bristles can be used to dislodge any stubborn
deposits, which should then also be removed by vacuum.
11. Do not use any chemicals to clean the heat exchanger.
12. The burner does not require any maintenance as it is self-cleaning.
Check that there are no cracks and/or other damage on the surface
of the burner. If the burner is damaged, replace it.
13. Reassemble in reverse order.
Fig.51
Restore water pressure
PN-0000382
Fig.52
Remove burner / door assembly
PN-0000394
9 Maintenance
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