Pump Head; Drain Tap; Pressure Gauge; Hydraulic Block Removal - Worcester Greenstar i Series Installation, Commissioning And Servicing Instructions

SERVICE AND SPARES

6.8.19 PUMP HEAD

▶ Ensure the boiler is fully drained).
▶ Disconnect the electrical connection from the bottom of the pump.
NOTICE: Water damage
▶ Protect the Control unit from water ingress when
removing the Pump head.
1. Remove the four Allen bolts securing the pump at each corner.
2. Gently pull the pump towards you and remove.
Fig. 117 Pump head removal
▶ To refit, follow the above in reverse.

6.8.20 DRAIN TAP

▶ Ensure the appliance has been fully drained.
1. Rotate the drain tap fully anti-clockwise.
2. Withdraw the drain tap from its housing
6.
5.
2.
Fig. 118
▶ To refit, follow the above in reverse. Ensure any seals that have been
disturbed are renewed.

6.8.21 PRESSURE GAUGE

▶ Refer to figure 118
▶ Ensure the appliance has been fully drained.
3. Prise the lugs apart (3) securing the pressure gauge to the fascia.
4. Remove the gauge (4) taking care not to damage or kink the capillary.
5. Withdraw the spring clip from the pressure sensing head housing.
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1.
1.
2.
1.
1.
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1.
4.
3.
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6. Remove the pressure sensing head and pressure gauge capillary from
the housing.
NOTICE: Heat damage
▶ Route the plastic capillary tube away from the pump
to ensure that the pipe is not melted against the hot
pump body.
▶ To refit, follow the above in reverse. DO NOT forget to fit the washer
from the capillary when fitting a replacement gauge.

6.8.22 HYDRAULIC BLOCK REMOVAL

Remove the syphon assembly.
Refer to Syphon assembly removal page 45
▶ Ensure the appliance has been fully drained.
▶ Disconnect the electrical connections to the NTC sensor, turbine and
pump.
▶ Undo the nuts securing the copper water pipes to the manifold (there
is no need to remove the gas pipe).
1. Release the spring clips securing these water pipes to the plastic
housing and remove the pipes.
▶ Release the spring clip securing the expansion vessel pipe to the
plastic housing and remove the pipe.
▶ Release the spring clip securing the pressure gauge sensing head to
the plastic housing and remove the sensing head.
▶ Release the locking devices that secure the two copper water pipes
leading to the combustion chamber by squeezing the two tabs
together and rotating anti-clockwise (viewed from above).
This is not essential but makes the removal of the block
easier.
▶ Remove the rubber pipe connecting the sump and remove the
syphon.
2. Undo the two screws securing the hydraulic block to the chassis
(located top left / top right of the housing).
1.
2.
Fig. 119 Hydraulic block removal part 1
3. Lift the left hand side of the block slightly.
4. Manoeuvre the block out, starting at the right hand side.
▶ Take care not to snag the harness.
2.
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