Sterling QVES - Manual (Page 6)

6
INSTALLATION
PUBLIC GARAGES: In repair garages, duct furnaces
must be installed in a detached building or room
separated from repair areas as specified in the latest
edition of NFPA 88B, Repair Garages.
In parking structures, duct furnaces must be installed
so that the burner flames are located a minimum of
18 inches (457mm) above the floor or protected by a
partition not less than 18 inches (457mm) high. Refer to
the latest edition of NFPA 88A, Parking Structures.
In Canada, installation must be in accordance with the
latest edition of CSA B149 “Installation Codes for Gas
Burning Appliances and Equipment.”
When the unit is equipped with an automatic gas ignition
system, the duct furnace must be installed such that the
gas ignition control system is not directly exposed to water
spray, rain or dripping water.
Duct furnaces should not be installed to maintain low
temperatures and/or freeze protection of buildings.
A minimum of 50°F (10°C) thermostat setting must
be maintained. If duct furnaces are operated to maintain
lower than 50°F (10°C), hot flue gases are cooled
inside the heat exchanger to the point where water
vapor (a fl ue gas by product) condenses onto the heat
exchanger walls. The result is a mildly corrosive acid
that prematurely corrodes the aluminized heat exchanger
and can actually drip water down from the duct furnace
onto fl oor surface. Additional duct furnaces should be
installed if a minimum 50°F (10°C) thermostat setting
cannot be maintained.
Do not install duct furnaces in corrosive
or fl ammable atmospheres! Premature failure of, or
severe damage to the unit will result!
Avoid locations where extreme drafts
can affect burner operation. Duct furnaces must not
be installed in locations where air for combustion
would contain chlorinated, halogenated or acidic
vapors. If located in such an environment, premature
failure of the unit will occur!
NOTICE: Location of duct furnaces is related directly
to the selection of sizes. Basic rules are as follows:
ACCESSIBILITY: If unit is a bottom service access type
allow a minimum of 21 inches (533mm) at the bottom of
the unit to facilitate servicing the burners and pilot, or
six inches (152mm) if the unit has a side access burner
drawer. Provision should also be made to assure acces-
sibility for recurrent maintenance purposes. See Table 1,
dimension “F” for required service clearance for burner
drawer on side service models.
AIRCRAFT HANGARS: Duct furnaces must be installed
in aircraft hangars and public garages as follows: In
aircraft hangars, duct furnaces must be at least 10 feet
(3.05m) above the upper surface of wings or engine
enclosures of the highest aircraft to be stored in the
hangar and 8 feet (2.4m) above the fl oor in shops, offi ces
and other sections of the hangar where aircraft are not
stored or housed. Refer to current ANSI/NFPA No. 409,
Aircraft Hangars. In Canada, installation is suitable
in aircraft hangars when acceptable to the enforcing
authorities.
CLEARANCES
DRAFTS: Avoid installing the duct fur nace in an
extremely drafty location. Strong drafts may cause pilot
outage. Units with intermittent pilot ignition may be
preferable in areas where drafts cannot be avoided.
Atmospheres containing commercial solvents or
chlorinated hydrocarbons will produce corrosive acids
when coming in contact with the fl ames. This will great-
ly reduce the life of the gas duct furnace and may void
the warranty. Avoid such areas.
NOTICE: If the gas duct furnace is to be used
in a building classified as having a hazardous
atmosphere, the installation must comply with
the standards set by the National Board of Fire
Underwriters. Consult the authorities having
jurisdiction before starting the job.
The duct furnace must be installed on the positive
pressure side of the air circulation blower.
Under no circumstances should
combustible material be located within the
clearances specifi ed in Table 3. Failure to provide
proper clearance could result in personal injury
or equipment damage from fi re.
Maintain adequate clearances around air openings into
combustion chamber:
Table 3 - Minimum Clearances †
† *21" (533 mm) is required
for accessibility on furnaces
with bottom access burner
compartments.
SIDES
TOP
BOTTOM*
FLUE
6" (152 mm)
6" (152 mm)
6" (152 mm)
6" (152 mm)
† When the clearances required
for accessibility are greater than
the minimum safety clearances,
the accessibility clearances take
precedence.