Supplied By www.heating spares.co Tel. 0161 620 6677
6
ROUTINE SERVICING
To ensure continued efficient operation of the appliance, it is
recommended that it is checked and serviced as necessary at regular
intervals. The frequency of servicing will depend upon the particular
installation conditions and usage, but in general once a year should be
adequate. It is the law that a competent person, such as British Gas or
other CORGI registered personnel, must carry out any service work.
Service the appliance by following the full procedure detailed below:
COMBUSTION CHECK
6.1
The appliance incorporates a flue sampling point on the appliance flue
elbow, or appliance vertical flue adaptor. If the service engineer has
suitable equipment to analyse the flue gas, the plastic cap may be
removed and a 6 mm inside diameter sample tube fitted. For CBX
appliances operate in DHW mode, at full rate, for SBX appliances
operate the appliance in Service mode, (see section 5.2). After ten
minutes operation check the CO
2
/CO values and compare with those
figures stated in section 2.3. Do not forget to replace the cap after use.
When the appliance is operating at maximum output check that the gas
supply pressure is 20.0 mbar, using the inlet pressure test point located
on the gas supply pipe.
Before commencing any service operation, ISOLATE the mains electrical
supply, and TURN OFF the gas supply at the main service cock.
GAS CONTROL
VALVE, FAN & BURNER ASSEMBLY
6.2
Refer to Figures 22, 23, 24, and 25
a)
Remove the casing front panel, pulls off.
b)
Lower the controls panel (2 screws).
c)
Remove the sealed chamber front panels (11 screws).
d)
Disconnect the igniter plug, earth lead and detection plug from the
igniter and detection electrodes.
22
CONTROL PANEL
23
COMBUSTION CASE PANELS
e)
Unscrew the screw holding the gas valve lead plug, and disconnect
the plug.
f)
Disconnect the electrical leads from the fan (2 plugs).
g)
Undo the nut holding the gas valve feed pipe to the gas isolating
cock, and disconnect.
h)
Disengage the gas valve feed pipe grommet from the casing by
pushing it up.
i)
Remove the 6 nuts holding the combustion chamber front cover in
place.
j)
Remove the gas control valve, fan & burner assembly, by carefully
pulling forward the combustion chamber front and rotating the
assembly anticlockwise so that the burner points forward, then
disengage the gas valve feed pipe from the casing, by lifting up the
assembly. Take care not to damage the insulation.
k)
The assembly may then be inspected.
l)
Re-assemble in reverse order.
BURNER
6.3
IGNITION & DETECTION ELECTRODES
6.4
Inspect, and if necessary clean the main burner ports using a soft brush
or vacuum cleaner. Do not use a wire brush or any abrasive material.
a)
Inspect the ignition and detection electrodes in situ. If necessary, clean
using a soft brush. If either the electrode or the ceramic insulation
shows signs of damage or wear, replace the electrode(s) and their
gasket.
b)
Check that the alignments of the ignition and detection electrodes are
correct. Refer to Figure 26. Adjust by carefully bending the tip of the
electrode rod whilst supporting the base of the rod. Do not put any
pressure on the ceramic insulation.
FIXING SCREWS
FIXING SCREWS
25
751030 MANUAL (NEW) 21/9/10 08:44 Page 43
