Servicing the Unit - Page 10
(See ‘BOILER SERVICING GUIDE’ label on the boiler)
Before servicing the appliance please read the
Important Information section on page 3.
After servicing, complete the relevant section of the
“Benchmark” Installation, Commissioning and Service
Record Log Book. This should be in the possession of the
user.
For economy and safety reasons, it is important to
service the appliance regularly.
1)
Turn off the electrical supply to the boiler.
2)
Remove the front panel of the outer case by pulling
forwards at the top and lifting upwards.
3)
Lift trim on flue pipe connection clear of the top panel
and remove the top panel of the outer case by pulling
upwards.
4)
Turn off the gas supply at the service tap and
disconnect the union (Fig 7).
5)
Disconnect the electrical socket by pulling upwards (Fig
7).
6)
Remove the four wing nuts and carefully withdraw the
burner and controls assembly. Remove the terminals
from the thermocouple interrupter (Fig 12).
7)
Release the two screws securing the front insulation
assembly and remove the assembly (Fig 9).
8)
Remove the four thumb screws securing the top
inspection panel (Fig 10). Remove the retaining bracket
and remove the casting baffles.
9)
Clean the fins of the heat exchanger with a stiff bristle
brush. Clean out any deposits that have collected in the
bottom of the combustion box ensuring that the two air
openings in the base are clear.
10) Remove any debris that may have collected under the
combustion box.
11) Check all the insulation panels for damage, replace if
necessary. Refit the front insulation panel, casting
baffles and retaining bracket the top inspection panel.
12) Clean the burner as follows:
a)
Pull and release the lint arrester from the front of
the combustion box panel held in position by two
spring clips. This can be cleaned by thoroughly
washing and then allowed to dry.
b)
Disconnect the burner by removing the 3 securing
screws (Fig 11).
c)
Brush any deposits from the blades and ensure
none of the ports are blocked. Clean any deposits
from the venturi.
d)
Remove the injector from the inlet manifold, clean
carefully and replace.
13) Clean the pilot as follows: Unscrew the pilot tubing nuts
at both ends and remove the pilot
tube. Remove and clean the pilot injector and clean the
pilot shroud (Fig 12).
14) Re-assemble the pilot components and then the burner
in reverse order of dismantling.
15) Refit the burner and controls assembly checking that
the door seal is undamaged. Replace if necessary.
Reconnect the T.T.B. terminals.
16) Reconnect the gas union at the service tap. Turn on the
tap and check for gas soundness.
17) Refit the electrical socket and turn the thermostat to the
OFF position.
18) Refit the outer case top panel.
19) Hold in the grey on/off button on the gas control valve
(Fig 7). Press in the igniter button and release. Repeat
until the pilot lights. Hold in the on/off button for a
further 20 seconds and then release. The pilot should
then stay alight.
(IF THE PILOT FAILS TO REMAIN ALIGHT, TURN
THE GREY ON/OFF BUTTON FULLY CLOCKWISE
AND RELEASE, WAIT 3 MINUTES AND START
AGAIN FROM 19.) The flame should be without a
yellow tip and be approximately 25mm (1 in) long. No
adjustment of the pilot flame is necessary as the pilot
jet is sized to give the correct flame length at 20 mbar
(8 in wg) inlet pressure.
20) Turn on the electricity supply to the boiler.
21) Remove the pressure test point screw (Fig 7). Connect
a pressure gauge and operate the burner by turning the
thermostat knob to its highest setting.
22) Check that the pressure corresponding to the range
rated output is correct for the installation (see data
label). If necessary adjust the appliance throttle (Fig 7).
23) Turn the boiler thermostat to the OFF position and refit
the pressure test point screw.
24) Turn the boiler thermostat to its original setting.
25) Replace the outer case front panel.
26) Complete the relevant section of the “Benchmark”
Installation, Commissioning and Service Record Log
and hand it back to the user.
