Replacement Of Parts; Removing Outer Case; Primary Sensor; Overheat Thermostat - Worcester Greenstar i Series Installation, Commissioning And Servicing Instructions

6.8

REPLACEMENT OF PARTS

CAUTION: Turn off the gas supply and isolate the mains
supplies before starting any work and observe all
relevant safety precautions.
NOTICE: REPLACEMENT OF COMPONENTS.
▶ After replacement of any components always check
for gas tightness where relevant and carry out
functional checks as described in Commissioning.
Damaged O-rings or gaskets must be replaced.

6.8.1 REMOVING OUTER CASE

1. Undo the two screws securing the top of the boiler casing.
2. Undo the two screws securing the bottom of the boiler casing.
▶ Pull the case forward and remove. To remove bottom tray, pull
forward on the tag on the underside of the tray.
1.
1.
2.
Fig. 88 Remove outer case
To gain access to the following components he outer
case has to be removed:

▶ Primary sensor

▶ Overheat thermostat

▶ Flue limit thermostat
6.8.2 PRIMARY SENSOR
Refer to figure 89 for removal.
1. Remove electrical connection by pulling upwards. Squeeze retaining
clip on plastic moulding of sensor and pull back and up until clear of
pocket in heat exchanger.
2. Pull forward to remove completely.
▶ Coat new sensor with heat conductive paste and replace.
6 720 804 532 (2012/09)
6.8.3 OVERHEAT THERMOSTAT
Refer to figure 89 for removal.
▶ Remove two electrical connectors from thermostat.
3. Slacken and remove fixing screw and thermostat (3).
▶ When replacing ensure thermostat sits correctly on surface of the
casting with the left hand side of thermostat sitting up against the
shoulder.
It is essential that the mating surface of the thermostat is
coated with heat conductive paste.
1.
Fig. 89 Primary sensor and overheat thermostat

6.8.4 FLUE OVERHEAT THERMOSTAT (WITH GROMMET)

To remove and replace the thermostat either:
▶ Using a small terminal screwdriver, prise the thermostat and grommet
from the plastic housing.
Take care not to damage the grommet or plastic housing.
-or-
1. Release the flue connection from the sump.
2. Push the flue tube up.
2.
1.
Fig. 90 Lower exhaust section
▶ Remove electrical connections.
▶ Push the flue limit thermostat in from the sump.
▶ Retrieve the thermostat from the sump well.
SERVICE AND SPARES
3.
2.
2.
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