Viessmann VITODENS 200 WB2A, Installation & Servicing Instructions Manual

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4 Installation Procedure
Combi
A Central heating flow
B Hot water outlet (Combi only)
C Gas connection
D Cold water inlet (Combi only)
E Central heating return
F Drain valve connection
System
A Central heating flow
B DHW cylinder flow (if required)
C Gas connection
D DHW cylinder return (if required)
E Central heating return
F Drain valve connection
Figure 4/E: Key - Boiler Service Connections
4.7.1 Horizontal Flues (Rear and Side Flues).
a)
Accurately measure the total flue length ‘L’ from the external wall face to the
centre line of the flue spigot as shown. If this distance is 640mm or less, no
further extensions will be required. (refer to Figure 4/F).
b)
Where the flue length is less than 640mm the flue pipe will require cutting.
The cut length is calculated L – 80mm.
Refer to Figure 4/E. Connect a suitable discharge pipe to the pressure relief valve outlet using a
tundish and pipework as required by the Building Regulations. The pipe between the appliance
and the tundish must be a minimum of 15 mm copper and run continually downwards.
NOTE: There is a safety device incorporated within the gas service cock which, when exposed
to heat (100°C) will shut off the gas supply. Care should be taken whilst connecting the gas
supply not to expose the gas service cock to heat sources e.g heat from blow torches.
If shut off does occur then the safety valve has to be replaced, as it cannot be re-set.
a)
Refer to Figure 4/E. Connect the gas supply to the gas inlet connection on the
gas cock. Upon completion, tighten the union connection.
b)
NOTE: The appliance is supplied adjusted for Natural Gas G20.
c)
If the appliance is to be used on Propane (G31) follow the instructions supplied
with the conversion kit.
4.5 Connecting the Gas Supply
4.6 Pressure Relief Valve Connection
4.7 Flue System Preparation
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