SERVICING AND SPARES
6 720 815 725 (2015/05)
50
26. HYDRAULIC BLOCK
▶ Ensure the appliance has been fully drained.
▶ Disconnect the electrical connections to the NTC, Turbine and pump.
▶ Undo the nuts securing the copper water pipes to the manifold (there
is no need to remove the gas pipe).
▶ 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.
▶ Undo the nut securing the pressure gauge to its bracket and remove
the gauge.
▶ Disconnect the pipe work to the pressure relief valve.
▶ Disconnect the drain pipe from the drain tap
(see e. g. step 1 in Fig. 96).
▶ 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).
1. Undo the two screws securing the hydraulic block to the chassis
(located top left/top right of the housing).
2. Lift the left hand side of the block slightly, then manoeuvre the block
out, starting with the right hand side.
▶ Take care not to snag the harness or pressure gauge bracket.
▶ To refit, follow the above in reverse. Ensure any seals that have been
disturbed are renewed.
Fig. 97 Hydraulic block removal
The block will still contain a small amount of water, which
will spill if the block is tilted.
1.
2.
6 720 812 176-16.1O