Worcester HEATSLAVE 9.24 RSF Installation And Maintenance Instructions Manual page 35

[g) Ensure a
'J '
bolt is located in the
bracke~
on each side of
the combustion chamber with the M4 washer and M4 w ing
nut at
~ he
start of the thread.
{h) Reassemble in the reverse order. Push each ' J' bo11 in an
upwards direction until they are located in 1he brackets on
the
inside of the boiler
casing.
(il .Test for gas soundness at thejointbetween t hepilotsupply
pipe tubing nut and pilot bracket as described in Section
15 Routine Cleaning and Inspection, Instruction B.
For replacement of the following parts the electrical tray must
be hinged down wards:
Unscrew
the hexagon
headed screw
at
the front insid9 edge
of each side panel and ease the electrical tray forwards off the
fovrbalf studs locating it to the rear of the applil:mce. Allow the
electrical tray to pivot vertically downwards supported by the
two plastic stops.
7. TO REPLACE THE BOILER HEAT EXCHANGER
!See
Fig. 37)
(a)
Drain down the heat ing system and the appliance.
NOTE:
A dra4n cock is fitted to the re ar right hand side of
the hot water heat exchenger. See Fig. 40.
!bt Remove t1'1e fan, f lue hood assembly and burner as
described in Section
'•5
Rout ine Cleaning and Inspection.
parts
3b,
c.
d.
e, f,
g . h, i, j, k ,
t,
m and n.
!cl
Removethecombustion chamber as described in parts 8b
and
c.
~d)
Unscrew the two fiat face union conf"'ections securi"\g the
heat exchanger to the water f low manifold and return
pipework .
(e) Ease the heat exchanger off t he pipework and lower out
of the
boiler
casing. Rernove the fibre sealing washers if
attached to the appliance pipeworl<.
(f)
Refit a new heat exchanger in t he reverse order using new
f ibre
sealing washers.
NOTE:
The heat exchanger will only fit in one direction. The
hea't exchanger pipes are offset and the heat exchanger is
installed w ith the smaller offset :awards the base ot !he
boiler.
Fig_ 37
Do not damage air seal gasket when
removing heat exchanger.
Unscrew flat face union connections.
Ease heat exchanger oft the pipe work
and lower out of boiler casing .
. 35
(g) Open all radiator valves and f ill the system venting as
necessary. The appliance is fitted wit h a manual air vent
on the outlet of t he black hot water heat exchanger. See
Fig.
40.
!h) Test for gas soundness atthe joint be1ween the pilot supply
pipe tubing nut and pilot bracket as described in Section
, 5
Routine Cleaning and Inspection, Instruction
8.
Check
the pilot
fl&me
size
as
described in Section
16
Replace-
ment of Parts, Instruc tion 3e.
li
1
Inspect the boiler f ront cover sealing gasket.lfthere is any
damage or det erioration replace t he inner cover.
til Replace the boiler inner cover
as
described in Section 15
Routine Cleaning and Inspection. Instruction 8'i).
8. TO REPLACE THE GAS VALVE
(See Fig . 35.)
(a) Disconnect the pilot supply pipe and the gas service cock
at the
onion f itting.
(bl Pull off the
t wo yellow
w ires
connected
to
the gas valve
terminals. Undo the fixing screw securir.9 the electrical
cover aside. Disconnect the leads at the push-on t erminals.
Unscrew the earth connection .
(c) Remove the four MS screws attaching the
gas
valve to the
gas manifold and aaso the valve out of the appliance !:ufti-
ciently to allow access to the rear. Do not lose the sealing
washer .
(dl
Undothefixing screw securing
the
rear
elec ~ rical
cover and
ease the electrical cover backwards. Disconr.eclt he push-
o n
termin als. Unscrew the earth terminal
and
remove
the
gas valve.
{e ) Remove the gas service cock union tail and l"!ut and fi1 to
!he
replacemMt
gas valve using a suit able sealing
com-
pound on the threads.
(f) Reassemble the gas valve in the reverse order taking care
to replace the sealing washer between t he gas valve and
manifold. The two yellow wires should be connected to the
g reen modureg coil on the gas valve
in
anv order. Check
that the correct mains connections to t he solen oid
operators have been made. Refer to the wiring diagram ,
Fig. 27.
fgl Turn
011
the gas at the gas service cock. Turn
or~
the elec·
t rica!
supply.
Heat exchanger.