Vermont Castings UVL18RN Installation And Operation Instructions Manual page 6

Example:
Gas Range
Vent-Free LogSet
Total
4. Compare the maximum BTU/hour rating the space
can support with the total BTU/hour used by the
appliances.
Example: 76,800 BTU/hour the space can support
80,000 BTU/hour used by appliances
In this example, the maximum BTU/hour that the
space can support is less than the total used by the
appliances.
The space is considered to be Confined Space.
Additional air must be provided to meet the require-
ments on the vent-free gas log set.
The installation and the provisions for combustion
and ventilation air must conform with the National
Fuel Gas Code, ANSI Z223.1, or the CSA-B149.1
Installation Code (Series).
A confined space may be ventilated in two ways:
A. Open up or provide at least two ventilating grilles to
an adjoining unconfined space. (Fig. 2)
Each of the two grilles must provide an opening of at
least 50 square inches, with all opening dimensions
being at least 3". One grille must be within 12" of the
ceiling; the other within 12" of the floor. (If the total
exceeds 100,000 BTU/hour, additional grilles will be
needed.)
Fig. 2 Ventilation options for confined spaces.
66
55,000 BTU/hour
+25,000 BTU/hour
80,000 BTU/hour
OPTION 1 -
Vents to
Adjoining
Room
B. Vent the room directly to the outdoors. (Provide
one square inch of opening for each 4,000 BTU/hr.)
For further information on ventilation guidelines and
sizing specifications, follow the National Fuel Gas
Code/NFPA 54/ANSI Z223.1, Section 5.3.
If the total BTU/hour used by the appliances is less
than the maximum BTU/hr the space can support,
the room meets the Unconfined Space criteria and
no further ventilation is needed.
WARNING
This heater shall not be installed in a confined
space or unusually tight construciton unless
provisions are made for adequate combustion
and ventilation air.
WARNING
If the area in which the heater may be operated
is smaller than that defined as an unconfined
space, or if the building is of unusually tight
construction, provide adequate combustion and
ventilation air by one of the methods described
in the National Fuel Gas Code, ANSI Z223.1,
1992, Sections 5.3, or applicable codes.
WARNING: Before installing the gas log set in a
solid-fuel burning fireplace, the chimney flue and
firebox must be cleaned of soot, creosote, and loose
paint by a qualified chimney cleaner.
OPTION 3 -
Vents to
Adjoining
Room
OPTION 2 -
Remove Door to
Adjoining Room
12"
12"
VO370-2
UVL Series