Bypass Valve; Access To Boiler Control Components; Replacing The Control Unit - Worcester 27i System Compact Installation, Commissioning And Servicing Instructions

SERVICE AND SPARES

6.8.22 BYPASS VALVE

Remove the hydraulic block from the boiler, refer to section 6.8.21.
1. Remove the clip on the return connection.
2. Remove the clip on the pump connection.
3. Remove the spring clip retaining the copper by-pass pipe.
4. Separate the return unit from the flow manifold assembly.
5. Using a pair of pliers remove the by-pass valve.
1.
4.
2.
5.
3.
Fig. 110
▶ When re-assembling, in reverse order, ensure that any seals that have
been disturbed are replaced.

6.8.23 ACCESS TO BOILER CONTROL COMPONENTS

1. Remove the three screws retaining the installer access cover.
2. The access cover can now be removed with the flap.
1.
Fig. 111 Installer access cover
50
2.
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.
1
1.
Fig. 112 Fuse holder

6.8.24 REPLACING THE CONTROL UNIT

The control unit is supplied within a plastic housing. The
complete unit must be replaced.
With the installer access cover removed:
1. Remove all the connectors
2. Slide out all the cable strain relief clamps
1.
2.
Fig. 113 Disconnect external connections
With the control unit in the service position:
1. Remove the access cover retaining screw.
2. Release the catches and remove the access cover.
▶ Disconnect and remove all cables and connectors from the control
unit.
▶ Remove the pressure gauge, refer to section 6.8.17.
Greenstar i System Compact - 6 720 807 726 (2013/05)
2.