System Design Considerations
20
VITOROND 200, VD2A
System Design Considerations
Burner Calibration
With 2-stage and fully modulating
burners, ensure that the chimney is
compatible with the lower flue gas
temperatures associated with partial load
conditions set on the burner.
Never operate boiler without an installed
venting system which safely vents all
products of combustion to the outdoors.
The vent system must comply with all
applicable local and/or national codes.
Vitorond 200, VD2A boilers are Category I
and III boilers as defined in ANSI Z21.13
when used with natural gas and LP. Venting
systems shall be sized and constructed in
accordance with approved engineering
methods (ASHRAE, HVAC Systems and
Equipment Handbook, Chapter 31
“Chimney, Gas Vent, and Fireplace
Systems”) including the chimney and boiler
manufacturer’s instructions.
In Canada
For gas-fired boilers install venting system in
accordance with all applicable local codes.
In the absence of local codes, follow
national codes CAN/CSA B149.1 or .2 or
latest edition.
For oil-fired boilers follow CSA B-139 or
latest edition.
In U.S.A.
For gas-fired boilers connecting to gas vents
or chimneys, vent installations shall be in
accordance with Venting of Equipment of
the National Fuel Gas Code, ANSI Z223.1 or
applicable provisions of the local building
codes.
For oil-fired boilers follow NFPA 31. Always
use latest code editions.
Venting (option #1)
The Vitorond 200, VD2A boiler is approved
as a
Category I
appliance and must be
vented accordingly.
Chimney
For proper operation of the Vitorond 200,
VD2A boiler, all products of combustion
must be safely vented to the outdoors, while
ensuring that flue gases do not cool
prematurely.
It is critical that the chimney system be
properly designed to handle the relatively
cool flue gas temperatures produced by the
Vitorond 200, VD2A boiler.
If the chimney system lacks sufficient
insulation and/or the chimney diameter is
too large, corrosive and damaging
condensation will result due to flue gases
cooling too quickly. If a calculated chimney
diameter lies between two values, the larger
diameter should be selected.
The chimney connection length between the
boiler vent pipe collar and the chimney must
be installed with insulation.
Vent pipe collar diameter does not
automatically indicate vent/chimney size.
We recommend consulting a reputable
chimney installer for advice in
project-specific circumstances.
When installing the Vitorond 200, VD2A
boiler, it is necessary to install a barometric
draft regulator in the chimney/vent for
proper operation of the boiler.
Install the barometric draft regulator within
5 to 7 ft. / 1½ to 2 m from the breeching
outlet located at the rear of the boiler.
Barometric draft regulator type
For natural gas or propane applications, use
a double-acting type. For #2 fuel oil
applications, use a single-acting type.
Barometric draft regulator diameter
The barometric draft regulator
must be the
same diameter
opening as the chimney for
which the vent is sized.
For example, a 14” chimney would require a
14” barometric draft regulator. Do
not
size
the barometric draft regulator to the
breeching outlet of the boiler, unless the
chimney is also intended to be of that
diameter.
The size of the flue gas outlet on the boiler
does not automatically determine the
horizontal breeching, or the actual chimney
diameter. The chimney size must be
designed for the actual boiler model and its
input.
Venting (option #2)
The Vitorond 200 boiler is a
Category III
positive pressure non-condensing boiler.
Each boiler must be vented individually.
The vent system must be properly designed
and suitable materials must be selected. The
chimney must be gas tight.
Use an AL29-4C® special stainless steel
venting system (UL/ULC listed for Category
III) for single-wall vertical venting of the
Vitorond 200 boiler.
For more details on the positive pressure
venting option, see the Viessmann
installation instructions for the positive
pressure venting system.
The following manufacturers may be
contacted for suitable stainless steel
chimneys:
ProTech Systems Inc.
26 Gansevoort Street
Albany, NY
12202
Tel.: (518) 463-7284
Fax: (518) 463-5271
Toll free: 1-800-766-3473
Selkirk Metalbestos
Selkirk Canada Corporation - head office
375 Green Road
Stoney Creek, ON
L8E 4A5
Tel.: (905) 662-6600
Fax: (905) 662-5352
Toll free:1-800-263-9308
Security Chimneys
Division of Security Chimneys Ltd.
2125 Monterey
Laval, PQ
H7L 3T6
Tel.: (450) 973-9999
Fax: (450) 973-2222
Toll free: 1-800-667-3387
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When installing or insulating (overhead)
piping or venting, do not stand on top
panel of boiler. Advise other trades
accordingly!
WARNING
The Vitorond 200, VD2A boiler is not
approved for side wall venting.
CAUTION
IMPORTANT
Barometric draft regulator
