Replacement Of Parts; Heat Exchanger - Viessmann VITODENS 200 WB2A Installation & Servicing Instructions Manual

9 Replacement of Parts

Before commencing any service operation, ISOLATE the mains supply and TURN OFF the gas
supply at the appliance service cock.
It is the law that any service work must be carried out by a registered person.

9.1 Heat Exchanger

a)
Close the isolation valves between the boiler and the central heating system.
Attach a suitable hose to the drain point on the lower right hand side of the
boiler and drain the boiler.
b)
Remove the outer casing as follows: Open the lower hinged controls cover.
Remove the upper decorative cabinet by pulling forward and place in a safe
position. Disconnect the fixing clips at the side of the control pod and hinge
the pod forwards.
c)
Remove the sealed chamber front panel by removing the two socket head
fixing screws at the bottom and hinge upwards unhooking from the top fixing
lugs. Place the cover in a safe position.
d)
Pull the electrical cable connector from the fan motor (A), pressure switch (B),
gas valve (C), ionisation electrode (D), and ignition unit (E).
e)
Disconnect the electrical connections from the boiler temperature sensor,
temperature limiter and flue gas temperature sensor.
f)
Disconnect the gas inlet union from the gas valve, release the gas pipe union
above the pipe connection frame and remove the gas connection pipe together
with its rubber bulkhead seal.
g)
Remove the four nuts (G) and remove the burner plate complete with the
burner, fan and gas valve.
h)
Remove the securing clip from the water connection between the flexible hose
from the expansion vessel to the flow pipe and disconnect.
i)
Remove the securing clips from the upper flow connection of the heat
exchanger and the lower flow connection above the rear bulkhead and remove
the pipe.
j)
Remove the retaining clip and the siphon.
Supplied By www.heating spares.co Tel. 0161 620 6677
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