Recommended Venting Practice - Viessmann Vitocrossal 300 CU3A Installation Instructions Manual

CU3A Venting Systems Installation
General Installation Information
Legend
A Boiler flue termination
CU3A 26-35 80 mm
CU3A 45-57 110 mm
B Combustion air intake 80 mm
C Combustion air 80 mm to 3 in. CPVC adaptor is
supplied with the boiler installation fittings
(May be used with CPVC/ABS air intake pipe system)
(continued)

Recommended venting practice

When installing a venting system the following
recommended venting practices apply:
Keep length and number of 90º elbows to a minimum.

Try not to use back-to-back 90º elbows.

Use 45º elbows where possible to minimize the number

of 90º elbows in case redirection of flue gas is required.
The special vent system shall not be routed into,

through, or within any other vent such as an existing
masonry or factory-built chimney.
Exception:
A masonry chimney flue may be used to route the venting
system only if no other appliance is vented in the same flue.
IMPORTANT
Route the flue gas connection to be free of load and
torque stresses. We recommend fitting an on-site support
immediately downstream of the boiler flue connection.
WARNING
The Vitocrossal 300 CU3A boiler cannot be common
vented with any other appliances including additional
Vitocrossal 300 CU3A boilers.
General Information
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