10.4 Hydraulics maintenance
10.4.1 Expansion vessel
Warning
Take precautions to protect other components from water damage
when removing the expansion vessel.
1. Close the flow and return isolation taps and drain the primary circuit.
2. Relieve the pressure from the expansion vessel.
3. Prise off the securing clips and disconnect the braided hose from the
vessel and hydraulic inlet assembly, taking care as water may still be
in the vessel.
4. Ensure that the braided hose is free of restriction, as a boiler with a
blocked hose will exhibit symptoms similar to one with a failed vessel.
Important
Where the hose is found to be blocked it must be cleared or
replaced and the vessel re-charged to 1 bar.
5. If the hose is clear support the vessel, undo the locknut and
manoeuvre the vessel out of the boiler.
6. Reassemble in reverse order and recharge to 1 bar.
10.4.2 Pump - complete
Warning
Take precautions to protect other components from water damage
when removing the pump and auto air vent.
1. Hinge the control box down.
2. Close the flow and return isolation taps and drain the boiler primary
circuit. Disconnect the electrical plugs from the pump motor.
3. Undo the screws securing the body to the pipe and manifold and draw
the pump forward to remove.
4. Examine the "O" ring seals on the return pipe and manifold, replacing
if necessary.
5. Reassemble in reverse order.
Fig.61
Removing the expansion vessel
PN-0000530
Fig.62
Removing the pump
PN-0000531
10 Maintenance
7696317 - 1 - 21032018
61