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18-CD37D1-2-EN
Installer’s Guide
Air duct systems should be installed in accordance with
standards for air conditioning systems, National Fire Protection
Association Pamphlet No. 90. They should be sized in
accordance with ACCA Manual D.
Central Furnaces, when used in connection with cooling units,
shall be installed in parallel or on the upstream side of the
cooling coil to avoid condensation in the heat exchanger. With
a parallel flow arrangement, the dampers or other means used
to control flow of air shall be adequate to prevent chilled air
from entering the Furnace, and if manually operated, must be
equipped with means to prevent operation of either unit unless
the damper is in full heat or cool position.
Flexible connections of nonflammable material may be used for
return air and discharge connections to reduce the transmission
of vibration. Though these units have been specifically
designed for quiet, vibration free operation, air ducts can act
as sounding boards and could, if poorly installed, result in
vibration to the annoyance level.
When the Furnace is located in a utility room adjacent to the
living area, the system should be carefully designed with
returns to minimize noise transmission through the return
air grille. Although these Furnaces are designed with large
blowers operating at moderate speeds, any blower moving
a high volume of air will produce audible noise which could
be objectionable when the unit is located very close to a
living area. It is often advisable to route the return air ducts
under the floor or through the attic. Such design permits the
installation of air return remote from the living area (i.e. central
hall).
When the Furnace is installed so that the supply ducts carry
air circulated by the Furnace to areas outside the space
containing the Furnace, the return air shall also be handled by
a duct(s) sealed to the Furnace and terminating outside the
space containing the Furnace.
DUCT CONNECTIONS
Exposure to the following substances in the combustion
air supply will also require OUTDOOR AIR for combus-
tion:
* Permanent wave solutions
* Chlorinated waxes and cleaners
* Chlorine based swimming pool chemicals
* Water softening chemicals
* Deicing salts or chemicals
* Carbon Tetrachloride
* Halogen type refrigerants
* Cleaning solvents (such as perchloroethylene)
* Printing inks, paint removers, varnish, etc.
* Hydrochloric acid
* Cements and glues
* Antistatic fabric softeners for clothes dryers
* Masonry acid washing materials
NOTE: Extended warranties are not available in some
instances. Extended warranty does not cover repairs to
equipment installed in establishments with corrosive at-
mospheres, including but limited to, dry cleaners, beauty
shops, and printing facilities.
Figure 11
Figure 12
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CAUTION
!
SAFETY HAZARD
Sharp Edge Hazard. Be careful of sharp edges on equip-
ment or any cuts made on sheet metal while installing or
servicing. Personal injury may result.