Viessmann VITODENS 200 WB2A, Installation & Servicing Instructions Manual

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9 Replacement of Parts
a)
Gain access by following step 9.1(b).
b)
Isolate the central circuit by closing the flow and return valves. Drain the
appliance using the drain point situated underneath the appliance at the bottom
right hand side.
c)
Slide out the clip securing the pressure gauge connecter to the casing above
the flow connection and pull out the connector.
NOTE: There may be a small discharge of water hence precautions should be taken.
d)
Release the seven plastic tabs securing the lid of the control pod and lift off
the lid.
e)
Push down gently and rotate in an anticlockwise direction the plastic clip
securing the back of the pressure gauge head and lift out the head.
f)
Carefully cut the cable ties securing the pressure gauge connecting tube to the
wire bundles and remove the gauge completely.
g)
Replace the pressure gauge and reassemble in reverse order re-attaching the
pressure tube to the wire bundles using suitable cable ties.
h)
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.
i)
Finally, ensure that the outer casing is secured in position warm up the system
and check for correct pressure readings.
9.21 Pressure Gauge
67