Replacement Of Failed Components; Igniter Assembly; Control Thermostat Renewal - Hamworthy Purewell Installation, Commisioning And Maintenance Instructions

13.3 Standard Diverter models: -
1) Check the flue above the draught diverter is self-
supporting before removing the two bolts on the
draught diverter clamp and sliding the primary flue up
inside the double cone assembly. The complete
assembly can be removed and stored safely. Lift flue
bezel and remove the top-casing panel by removing
the relevant screws. Lift off and store in a safe place
to avoid damage or scratching.
2) Undo the screws supporting the gas pipe clamp.
NOTE! The boiler gas pipe may require supporting in
order not to place undue stress on the main gas
header pipe.
3) Carefully prise away the silver insulation jacket from
the flue hood. Undo and remove the nuts holding the
flue hood to the boiler. Take care not to move the
locking nuts which locate the hood's position. Remove
the gas baffle, (not fitted to 120kW boiler).
13.4 Low Line models: -
1) Check the flue above the flue pipe is self-supporting.
Remove the top panel to gain access to the draught
diverter. Remove the insulation and inspection cover
(M6) bolts on sloping front.
2) If further access is required remove M6 bolts along
top of draught diverter. The top section should now
drop down to free the flue pipe. Undo M6 bolts from
baffle and swing away.
3) NOTE! This baffle MUST be relocated in the correct
position when re-assembling the draught diverter.
4) All models: - The boiler flueways are now exposed
and can be brushed through diagonally in both
directions to remove deposits from the cast iron finned
surfaces. Re-assemble the boiler in the reverse order
to that shown above. Ensure a new rope seal is fitted
to the flue hood to maintain a gas tight seal, (see
spares list). Ensure primary flue is sealed into flue
hood spigot. The boiler's operation may be affected
if this seal is not completely fitted. Before replacing
the burner bar assembly, lift out both halves of the
radiant reflector and brush off any dust and fallen
deposits accumulated on it. Also clean the area under
the reflector before re-placing it in its correct location.
Re-assemble the burner bar assembly, ensuring
correct location on the rear support bracket. Refit the
gas manifold taking care not to damage any fragile
components. Check all gas connections are tightened
securely before opening the gas service cock. Switch
on the electricity supply and re-light the boiler following
the correct procedure on the inside of the door.
Take gas pressure readings and exhaust gas readings
and compare with Figure No. 1, or for propane firing
refer to Appendix 'A', adjust as required. Ensure no
gas leaks are evident from the gas connections, see
Figure No. 3 for procedure. Check thermostat settings
and adjust if required.
HAMWORTHY HEATING LTD.
Re-fit door and tidy floor around boiler as necessary.

14.0 REPLACEMENT OF FAILED COMPONENTS

There are a number of components listed below which
can be replaced simply and quickly by following the
given procedure. In each case carrying out the
appropriate part of the commissioning procedure must
check the operation of each replaced component. See
Section 11.0:Commissioning and Testing
NOTE: Isolate electrical supply to the boiler and
turn off the gas supply before removing controls
cover and commencing any servicing or
component exchange procedure.

14.1 Igniter Assembly

Reference to Figure No. 10 shows position of igniter
assembly. To remove assembly the igniter lead must
first be disconnected from the electrode, (Protective
boot to be pulled down cable to reveal connector).
Figure No. 14 shows diagram of igniter assembly and
relevant components and part numbers. Renew
components as required and generally remove any
loose sooty deposits and clean as required. Ensure
positions of components are as recommended in
Figure No. 14 (ensure protective boot is replaced over
electrode).

14.2 Control Thermostat Renewal.

Part No. 339009345 or 533901178
Alternative thermostat manufacturers may be used in
the Purewell boiler controls assembly. However, the
fitting and wire spade connections are physically
identical. The terminal identification may well be
different from that shown on the wiring diagram inside
the fascia. Please refer to thermostat to ensure correct
connections are made and correct operation is
obtained.
To replace the thermostat the following procedure
must be followed. NOTE! Record existing temperature
setting of thermostat for reference before removal.
Remove holding screws underneath and lift boiler top
panel to reveal thermostat pocket. Carefully remove
thermostat phials. Drop down fascia to reveal controls
section. Remove the 'push on' spade connectors from
the thermostat body noting position of coloured cables.
Pull off the control knob and remove bezel. (Note!
The two M3 screws holding the thermostat to its
bracket may retain this). Note if screws are of different
type/length for re-assembly purposes before removing
them. The thermostat body can now be removed by
gently feeding capillary through the controls bulkhead.
Fit the new thermostat and ensure the capillary is
correctly located within the pocket. Do not force the
bulb into the pocket by placing undue stress on the
capillary. Close fascia and re-fit top panel correctly.
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PUREWELL AUTOMATIC IGNITION 500001035/G