Rheem LX2000 Series User Manual

6
conditions, two openings of
approximately equal area (one located
near the top and one located near the
bottom of the enclosure) must be
provided each with a total free area of not
less than 1 square inch per 4,000 BTU’s /
Hr. of total input rating of all appliances in
the enclosure (see figure 3).
If horizontal ducts are used, each
opening shall have a free area of not
less than 1 sq. in. per 2,000 BTU/HR of
total input of all appliances in the
enclosure (see figure 4).
Appliances installed in confined
spaces may be installed with ventilation
air from inside the building and
combustion air from outdoors. Consult
state and local codes and the
NFPA
No. 31, Standard for Installation of Oil
Burning Equipment
for specific details
(see figure 5 for an example).
Appliances installed in confined
spaces with all required air coming
from the outdoors may also get inlet
air from continuously ventilated crawl
spaces and outlet air to a ventilated
attic (see figure 6).
"NFPA 31, Standard for Installation of
Oil Burning Equipment"
defines
"confined space" and "unconfined
space" as follows.
Confined Space - Any space whose
volume is less than 50 cu. ft. per 1,000
BTU/HR (4.8 M3 per KW) of the
aggregate input rating of all fuel-burning
appliances installed therein.
Unconfined Space - Any space whose
volume is equal to or greater than 50
cu. ft. per 1,000 BTU/HR (4.8 M3 per
KW) of the aggregate input rating of all
fuel-burning appliances installed
therein. Rooms connecting directly with
the space in which the appliances are
located by means of openings that have
no doors or closures, unless fully
louvered, shall be considered part of the
unconfined space.
When determining if the furnace is
located in a confined or unconfined
space it is important to realize that
some buildings are so tight that normal
infiltration does not meet air
requirements for proper combustion or
venting and outside air must be
introduced.
Important: All applicable codes must
be followed when providing air to the
confined space.
Figure 3
All air from ventilated attic
Figure 4
Directly connecting horizontal
ducts to outdoors
Figure 5
Inside Ventilation Air, Outside
Combustion Air
Figure 6
Outside Air From Attic and Crawl Space

Rheem LX2000 Series Specifications

General

Brand	Rheem
Model	LX2000 Series
Category	Furnace
Language	English