Desa VRL24PR Water Heater User Manual


 
www.desatech.com
110021-01M
8
INSTALLATION
NOTICE: This heater is intended
for use as supplemental heat.
Use this heater along with your
primary heating system. Do not
install this heater as your pri-
mary heat source. If you have a
central heating system, you may
run system’s circulating blower
while using heater. This will help
circulate the heat throughout the
house. In the event of a power
outage, you can use this heater
as your primary heat source.
AIR FOR COMBUSTION
AND VENTILATION
Continued
Figure 2 - Ventilation Air from Inside
Building
Figure 3 - Ventilation Air from Outdoors
Outlet
Air
Ventilated
Attic
Outlet
A
ir
Inlet
Air
Inlet Air
Ve
ntilated
Crawl Space
To
Crawl
Space
To Attic
Or
Remove
Door into
Adjoining
Room,
Option
3
Ventilation Grills
Into Adjoining Room,
Option
2
Ve
ntilation
Grills
Into Adjoining
Room,
Option 1
12"
12"
If the actual Btu/Hr used is less than the maximum
Btu/Hr the space can support, the space is an un-
confined space. You will need no additional fresh
air ventilation.
WARNING: If the area in
which the heater may be oper
-
ated 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/NFPA 54 Section 5.3
or applicable local codes.
VENTILATION AIR
Ventilation Air From Inside Building
This fresh air would come from an adjoining un-
confined space. When ventilating to an adjoining
unconfined space, you must provide two perma-
nent openings: one within 12" of the ceiling and
one within 12" of the floor on the wall connecting
the two spaces (see options 1 and 2, Figure 2). You
can also remove door into adjoining room (see
option 3, Figure 2). Follow the National Fuel Gas
Code ANSI Z223.1/NFPA 54, Section 5.3, Air for
Combustion and Ventilation for required size of
ventilation grills or ducts.
Ventilation Air From Outdoors
Provide extra fresh air by using ventilation grills or
ducts. You must provide two permanent openings:
one within 12" of the ceiling and one within 12"
of the floor. Connect these items directly to the
outdoors or spaces open to the outdoors. These
spaces include attics and crawl spaces. Follow the
National Fuel Gas Code ANSI Z223.1/NFPA 54,
Section 5.3, Air for Combustion and Ventilation for
required size of ventilation grills or ducts.
IMPORTANT: Do not provide openings for inlet
or outlet air into attic if attic has a thermostat-
controlled power vent. Heated air entering the attic
will activate the power vent.