22
Concord CXS -
Installation & Servicing
SER
VICING
SERVICING
27 SERVICING - continued
Unscrew the extended nuts at the top of the NOx duct behind
the control box and lift the NOx duct clear of the burners as
illustrated below.
Undo the wing nuts securing the burner front plate. Pull the
front plate forwards, at the top, and lift it out,
taking care not to
damage the insulation or the detection electrode
.
On the
CXS 40, 50 & 60
remove the screws holding the HT
heat shield from the LH leg of the combustion chamber. Raise
slightly and withdraw the heat shield,
taking care not to
damage the leads.
The burners may be lifted out after they have been pushed
back to clear the injectors. Take care not to damage the
ignition electrode assembly and carefully detach the ignition
leads when removing the left hand burner. Take care not to
damage the detection electrode when removing the RH burner.
GENERAL
WARNING
ALWAYS turn OFF the gas supply at the gas inlet
cock and DISCONNECT the electricity supply
BEFORE WORKING on the APPLIANCE.
To facilitate the replacement of components, remove
and replace the lower front panel, NOx duct and the
burner front plate as necessary - described under
‘Servicing’.
condition.
In particular, check that:
1.
The ignition electrode shield and base fixing screws are
tight.
2.
The electrodes are correctly positioned. Refer to Frames
31 or 32.
3.
Reassemble in reverse order. Refit the flue baffles,
cleanout cover, NOx duct, and casing panels.
TESTING AFTER SERVICING
After re-assembly, restore the electricity and gas supplies.
Light the boiler. Refer to the Lighting Instructions and also
Frame 19 ‘Testing for Gas Soundness’ .
Check burner manifold pressures (Frame 21) and adjust if
necessary (Frame 21).
Finally, reset any external controls to the desired position.
Undo the screws securing the cleanout cover
and lift it off to give access to the flueways.
Lift out the flue baffles (
not fitted to the CXS
110 & 120).
Remove all loose deposits from the heat
exchanger (especially from between the fins),
using the brush provided, and remove all
debris from the combustion chamber floor.
Examine the burner assembly. Clean the
burner bars by brushing them down with a stiff
bristle (not wire) brush. Check each bar
carefully to ensure that all flame ports are
clear, that there are no cracks and that all
surfaces are free from accumulated deposits.
If available, an industrial vacuum cleaner may
be useful to assist in this work. When cleaning
the burner bars, take care to avoid damage
from rough handling to the ignition or detection
electrodes.
Inspect the ignition and detection electrodes.
Ensure that they are clean and in good
28 REPLACEMENT OF COMPONENTS - Refer to Frames 5, 31, 32 and 33.
