Recommended Venting Practice; Leak Test (For Coaxial Venting Systems Only) - Viessmann Vitodens 100-W WB1B Series Installation Instructions Manual

General Information
General Installation Information

Recommended venting practice

Leak test (for coaxial venting systems only)

Viessmann recommends that the heating contractor perform
a simplified leak test during boiler start-up. For this purpose
it is sufficient to measure the CO
combustion air in the annular gap of the air intake pipe.
The vent pipe is considered sufficiently leak-proof if a CO
concentration in the combustion air no higher than 0.2%
or an O concentration no lower than 20.6% is measured
2
relative to a starting O
2
12
concentration of the
2
concentration of 20.9%.
Rigid Venting Systems Installation Instructions
(continued)
When installing a venting system the following
recommended venting practices apply:
Keep length and number of 90º elbows to a minimum.
g
Try not to use back-to-back 90º elbows.
g
Use 45º elbows where possible to minimize the number
g
of 90º elbows in case redirection of flue gas is required.
The special vent system shall not be routed into,
g
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.
If higher CO values or lower O
2
inspect the venting system thoroughly.
Continuous short cycling of the boiler can indicate a leaking
venting system.
2
Note: The vent pipe adaptor comes with two measurement
ports, one for combustion air intake measurement
and one for flue gas measurement.
values are measured,
2