Viessmann VITODENS 200 WB2A, Installation & Servicing Instructions Manual

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NOTE: There may be a small discharge of water hence precautions should be taken.
e)
If a rear flue is fitted it is necessary to temporarily disconnect the flue system.
f)
Unscrew the automatic air vent situated at the top of the boiler behind the flue
connector.
g)
Unscrew the eight screws securing the top rear cover and remove the cover.
h)
Lift out the expansion vessel. Replace and reassemble in reverse order. Check
the expansion vessel pre-charge pressure.
i)
Connect the filling loop, open the CH flow and return valves and re-pressurise
the system to design pressure using the filling loop valves and venting as
necessary. Check all connections for soundness and then disconnect the
filling loop.
j)
Finally, ensure that the outer casing is secured in position warm up the system
and check for leaks and correct pressure readings.
9 Replacement of Parts
9.23 Expansion Vessel
69