SERVICE AND SPARES
6 720 803 800 (2012/11)
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6.8.22 DRAIN TAP
▶ Ensure that the boiler is full drained down.
▶ The drain tap rotates anticlockwise for a ¼ turn to open.
1. Rotate the drain tap fully anticlockwise passed the ¼ turn stop point to
release.
2. Push in and withdraw from the housing.
Fig. 110 Drain tap
6.8.23 CH PRESSURE RELIEF VALVE
▶ Isolate the boiler and ensure that the boiler is fully drained.
1. Release the knurled connector from the bottom of the PRV.
2. Pull the captive clip to the left to release the PRV.
3. Pull the Central Heating pressure relief valve out of the housing.
▶ Replace in reverse order, secure with the clip and mounting screws.
Fig. 111 PRV
6.8.24 DHW PRESSURE RELIEF VALVE
1. Release the retaining clip
2. Pull the pressure relief valve (1) with the deflector (2) from the
housing.
▶ When replacing the DHW pressure relief valve, re-use the deflector
from the old PRV.
Fig. 112 DHW PRV
6.8.25 DHW PLATE HEAT EXCHANGER
1. Undo and remove the retaining screw.
2. Rotate the left hand side of the heat exchanger towards you and slide
out to the left.
Fig. 113 Remove plate heat exchanger.
▶ When replacing the heat exchanger, ensure that any seals that have
been disturbed are replaced.
6.8.26 HYDRAULIC BLOCK REMOVAL
1. Squeeze the ratchet connector and rotate clockwise to release.
2. Release the pin on the expansion vessel connector at the pump
assembly.
3. Pull the expansion vessel up and secure in raised position.
4. Remove the clip securing the pump return to the heat exchanger.
Before removal:
▶ Isolate the electrical power to the boiler.
▶ Drain the boiler.
▶ Isolate the cold water mains.
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Before removal:
▶ Isolate the electrical power to the boiler.
▶ Isolate the cold water mains and drain DHW circuit
within the boiler.
▶ Drain the boiler.
Do not remove the hydraulic block assembly unless
absolutely necessary.
Before removal:
▶ Isolate the electrical power to the boiler.
▶ Drain the boiler.
▶ Isolate the cold water mains and drain the DHW circuit
within the boiler.
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