6
Vermont Castings Radiance
Installation Requirements
THIS HEATER MUST HAVE FRESH AIR FOR
PROPER OPERATION. IF NOT, POOR FUEL
COMBUSTION COULD RESULT. READ THE
FOLLOWING INSTRUCTIONS TO INSURE PROPER
FRESH AIR FOR THIS AND OTHER FUEL-BURNING
APPLIANCES IN YOUR HOME.
WARNING
Fresh Air Requirements for
Combustion and Ventilation
Modern construction standards have resulted in homes
that are highly energy-efficient and that allow little heat
loss. Your home needs to breathe, however, and all
fuel-burning appliances within it require fresh air in
order to function properly and safely. Exhaust fans,
clothes dryers, fireplaces, and other fuel burning
appliances all use the air inside the building. If the
available fresh air is insufficient to meet the demands
of these appliances, problems can result.
The Radiance Unvented heater has specific fresh
air requirements.
You must determine that these
fresh air requirements will be met within the space
where the appliance will be installed. The following
information will help you insure that adequate fresh air
is available for the heater to function properly.
Provide For Adequate Ventilation
Any space within a home can be classified in the
following categories:
1) Unusually Tight Construction
2) Confined Space
3) Unconfined Space
First, determine which classification defines the
intended space.
Unusually Tight Construction
You must provide additional fresh air if the space falls
into this classification.
Unusually Tight Construction is
defined as construction wherein:
a. walls and ceilings exposed to the outside atmo-
sphere have a continuous water vapor retarder with a
rating of one perm or less with openings gasketed or
sealed
and
b. weather stripping has been added on openable
windows and doors
and
c. caulking or sealants are applied to areas such as
joints around window and door frames, between sole
plates and floors, between wall-ceiling joints, between
wall panels, at penetrations for plumbing, electrical,
and gas lines, and at other openings.
If your home meets all of the three criteria above,
you must provide supplemental fresh air for the appli-
ance from outside the home as detailed on page 7, B.
If your home does not meet the above criteria,
follow the procedure below.
Determine if You Have a Confined or
Unconfined Space
Use the following formula to determine if you have a
confined or unconfined space.
Space is defined as the room in which you will
install the heater plus any adjoining rooms with
doorless passageways or ventilation grilles between
the rooms.
The National Fuel Gas Code defines a confined
space as a space whose volume is less than 50 cubic
feet per 1,000 BTU per hour, (4.8 m3 per kw), of the
aggregate input rating of all appliances installed in that
space and an unconfined space as a space whose
volume is not less than 50 cubic feet per 1,000 BTU
per hour, (4.8 m3 per kw), of the aggregate input rating
of all appliances installed in that space. Rooms com-
municating directly with the space in which the appli-
ances are installed, through openings not furnished
with doors, are considered a part of the unconfined
space.
1. Determine the volume of space, (length x width x
height)
. Include adjoining rooms connected by doorless
passageways or ventilating grilles.
Example:
A room that is 18' x 12' x 8' has a volume of 1728
cubic feet, ( length x width x height). An adjoining open
kitchen that is 10' x 12' x 8' has a volume of 960 cubic
feet. An adjoining open dining room is 12' x 12' x 8'
with a volume of 1152 cubic feet. The total space
volume is 3840 cubic feet. (1728 + 960 + 1152).
2. Divide the volume of space by 50 cubic feet.
The result is the maximum BTU/Hr that the space can
support.
Example:
3840 divided by 50 = 76.8 or 76,800 BTU/Hr.
