Worcester Greenstar 25Si Compact - Service and Spares (Continued); 7.8.27 Hydraulic Block Removal; 7.8.28 Bypass Valve; 7.8.29 Access to Boiler Control Components

SERVICE AND SPARES
Greenstar Si Compact
ErP
- 6 720 813 278 (2015/07) 55
7.8.27 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.
5. Release the knurled connector securing the CH pressure relief valve to
the PRV pipe work.
6. Remove the screws securing the hydraulic block assembly.
Fig. 112 Hydraulic block
7.8.28 BYPASS VALVE
Remove the hydraulic block from the boiler.
1. Remove the clip on the return connection.
2. Remove the clip on the pump connection.
3. Remove the spring clip retaining the by-pass pipe.
4. Separate the return unit from the flow manifold.
5. Using a pair of pliers remove the by-pass valve.
Fig. 113 Bypass valve
▶ When re-assembling, in reverse order, ensure that any seals that have
been disturbed are replaced.
7.8.29 ACCESS TO BOILER CONTROL COMPONENTS
1. Release the three captive screws retaining the installer access cover.
2. The access cover can now be removed with the flap.
Fig. 114 Installer access cover
PCB FUSE
The fuse is located next to the high voltage connectors and the spare
fuse (1) is located on the back of the access cover.
To remove the fuse:
1. Push the top of the fuse holder up.
2. Rotate the top of the fuse holder anti-clockwise and remove.
Fig. 115 Fuse holder
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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