Instructions To The User; Inspection And Service - Worcester Highflow 400 RSF Installation And Servicing Instructions

refer to Section 13, Users Instructions and set the controls to the
user's requirements.
If the appliance is to be left inoperative check that the Operating
Switch or programmer is set to OFF. Turn the gas service cock to
off and switch off the electricity supply.
If there is any possibility of the appliance and system being left
inoperative during frosty conditions then drain the appliance
and system.
For short inoperative periods leave the appliance under the
control of a frost thermostat, if fitted, or operating continuously
under the control of a room thermostat set at 6°C.

13. Instructions to the User

13.1 Tell the user how to operate the appliance and hand over
the Users Instructions leaflet.
13.2 Tell the user what to do if the heating system is not to be
used in frosty weather. Also tell the user that if the appliance is
not to be used for long periods during frosty weather, the system
must be drained and the gas and electricity supplies turned off.
13.3 Tell the user the Sealed System set pressure if applicable.
13.4 Tell the user of the importance of regular servicing.
Worcester Heat Systems Ltd offer a comprehensive maintenance
contract.
13.5 Set the system controls to the users requirements.
13.6 If an external programmer has been fitted which has a
programmable hot water facility then instruct the user how to
set up the programme.
14. Inspection and Servicing
To ensure continued efficient operation of the appliance it must
be checked and serviced as necessary at regular intervals. The
frequency of servicing will depend upon the particular
installation conditions and usage, but once per year should
generally be adequate. The extent of the service required by
the appliance is determined by the operating condition of the
appliance when tested by fully qualified engineers.
It is the law that any service work must be carried out by
competent engineers such as British Gas or Corgi registered
personnel.
14.1 PRE-SERVICE INSPECTION.
Check that the flue terminal and the terminal guard, if fitted, are
clear.
If the appliance is in a compartment check that the ventilation
openings in the compartment door or walls are clear. Refer to
Section 6, Air Supply.
Check the system and remake any joints or fittings which show
signs of leakage. Refill, vent and re-pressurise sealed systems as
described in Section 12, Commissioning.
Operate the appliance and the system taking note of any faults.
WARNING:
Disconnect the electrical supply at the mains and turn off the
gas supply at the gas service cock on the appliance before
servicing the appliance. See Fig.16.
After completing the service always test for gas soundness as
indicated in BS 6891.
14.2 DISMANTLE THE APPLIANCE.
To carry out a full and comprehensive service of the appliance
remove the following parts to gain access to the components
which need to be checked or serviced.
(a) Cabinet Front Panel.
Lift off the top location and clear the lower return over the kick
strip. See Fig. 14.
(b) Facia and Control Box.
Remove the cabinet front panel. Unscrew the two screws
securing the facia to the outer edges of the cabinet, accessible
under the facia. Ease the facia forwards on the slide rails until
fully extended. Lift the facia and control box upwards through
90° into the Service Position. Lodge in the Service Position on the
outer locations. See Fig. 14.
(c) Expansion Vessel.
Unscrew one screw securing the expansion vessel support
bracket to the right hand side panel. Lower the vessel gently
until resting on the floor. See Fig. 16.
(d) Inner Casing Cover.
Repeat operations a, b and c. Unscrew the four screws securing
the cover to the inner casing and lift off. See Fig. 16.
(e) Fan.
Repeat operations a,b,c and d. Ease the two electrical
connections from the fan motor and the two flexible pipes from
the venturi housing. Unscrew the two screws securing the front
of the fan mounting plate to the flue hood. Ease the fan
assembly out of the flue bend or flue adaptor by gently pulling
the mounting plate forwards about 20 mm to clear the flue bend
or flue adaptor. Remove the fan and mounting plate assembly
from the inner casing. Ensure the short leg of the venturi faces
into the fan. See Fig. 35.
(f) Flue Hood.
Repeat operations a,b,c,d and e. Unscrew the two screws
locating the front of the flue hood to the combustion chamber
cover. Ease the flue hood forwards about 15 mm to clear the rear
location. Remove the flue hood off the heat exchanger and clear
of the inner casing. See Fig. 35.
(g) Combustion Chamber Cover.
Repeat operations a,b,c,d,e, and f. Unscrew the four screws
securing the combustion chamber cover and remove the cover.
See Fig. 35.
(h) Burner.
Repeat operations a,b,c,d,e,f and g. Unscrew the two screws
securing the pilot bracket to the burner. Unscrew the two screws
securing the front of the burner to the burner bracket located
inside the inner casing. Remove the burner by easing upwards
and forwards off the main burner injector and clear of the pilot
bracket. See Fig. 35.
(i) Pilot Bracket.
Repeat operations a,b,c,d,e,f and g. Unscrew the two screws
securing the pilot bracket to the burner bracket. Unclip the spark
igniter and remove.
Support the pilot bracket with a suitable tool. Unscrew the pilot
pipe union nut and ease the pipe clear of the bracket. Remove
the pilot injector from the pilot bracket. See Figs. 34 and 35.
14.3 Servicing of Components.
Clean the Fan.
Unscrew the three screws securing the fan mounting plate to the
fan. Unscrew the two screws securing the venturi assembly to
the fan and ease out of the fan outlet. Any dust or fluff
accumulated on the fan or venturi should be removed with a soft
brush or by blowing. Reassemble the venturi and fan mounting
plate in the reverse order. See Fig. 35.
Clean the Burner.
Brush the blade tops and mixing tube with a soft brush and
check that all the flame ports are clear. Remove any blockages
with a non-metallic brush.
Clean the Main Burner Injector.
Inspect the main burner injector located at the rear of the inner
casing. Clean with a soft brush. Do not use a wire brush or
anything likely to cause damage.
Clean the Pilot Bracket.
Brush with a soft brush. Clean the pilot injector by rinsing it in
warm water. Check the condition of the electrode.
Clean the Gas to Water Heat Exchanger.
Cover the main burner injector and pilot bracket with a cloth.
Clean the heat exchanger using a soft brush. Remove the
deposits from the bottom of the combustion chamber. The heat
exchanger is manufactured from copper take care not distort
any of the fins.
Combustion Chamber Insulation.
Examine and replace any pads that are damaged.
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