Glow-worm Ultrapower sxi Range - Manual (Page 56)

56
15 Replacement of Parts
15.1 General
Replacement of parts must be carried out by a competent
person approved at the time by the Health and Safety
Executive.
IMPORTANT:
The following replacement of parts described
in sections 15.7 to 15.12 and section 15.14 will require the
removal of the burner module assembly and the replacement
of seal and self locking nuts.
Replacement parts that have associated components that
need replacing on removal, i.e. ‘O’ ring, seals, gasket, etc.,
will be supplied and should be fitted.
Before replacing any parts the boiler and immersion heater
should be isolated from the mains electric supply and the gas
should be turned off at the gas service isolation valve on the
boiler, see diagram 12.1.
Unless stated otherwise parts are replaced in the reverse
order to removal.
After replacing any parts always test for gas soundness and if
necessary carry out functional test of the controls.
For replacement of parts the front casing panels will need to
be removed.
The tank module front panel will need to be removed first to
gain access to the boiler module front panel securing screws.
Remove the two screws on the underside of the panel and lift
off, see diagram 13.2.
For ease of servicing, the control box and domestic expansion
vessel can be moved into their service positions, this will
improve access to hydraulic components, see diagrams 13.4
to 13.6.
Draining of Boiler Heating Circuit
To drain the boiler heating circuit, isolate the flow and return
valves, see diagram 12.1.
Open the top tap on the filling loop to drain the boiler out
through the filling loop hose.
After servicing or replacing parts open the heating flow and
return isolating valves and refill, vent and pressurise the
heating circuit, refer to section 12.3.
Close the drain valve and disconnect the hose.
Check for leaks.
Draining of Boiler Domestic Water Circuit
Drain the domestic water circuit by closing the cold-water
isolation valve, see diagram 12.1.
Open one or more hot water taps to drain the hot water circuit.
After servicing or replacing parts open the cold-water isolation
valve and slowly open a hot water tap to remove air. Close the
hot water tap and check for any leaks.
15.2 Domestic Expansion Vessel
For access, refer to section 15.1.
Isolate the DHW inlet valve, see diagram 12.1 and drain
through a domestic tap.
Loosen the locknut at the top of the vessel, see diagram 15.1.
To remove the expansion vessel slide forward out of its
hanging bracket.
Remove the flexible hose from the expansion vessel by
undoing the union nut and lock nut, see diagram 15.1.
Fit a new rubber seal in union nut on flexible hose.
Fit the replacement unit.
Refill, vent and pressurise the boiler.
Check for leaks.
Diagram 15.2
13341
IGNITER
UNIT
BRACKET
SECURING
SCREW
(2 OFF)
IGNITION
LEAD
ELECTRICAL
CONNECTION
13330
DOMESTIC
EXPANSION VESSEL
FLEXIBLE
HOSE
BRACKET
UNION NUT
LOCK NUT
Diagram 15.1
15.3 Silencer assembly
For access, refer to section 15.1.
To aid access to the silencer and securing screw, slacken
the locknut at the top of the domestic expansion vessel, see
diagram 15.1 and slide the vessel forward out of its bracket
and put in its service position, see diagram 13.6.
To remove, undo the securing screw and pull the silencer from
the fan, this is a push fit so no tools or fixings are required for
its removal or fitting, see diagram 13.7.