StyleCrest Installation Manual

4
CIRCULATING AIR REQUIREMENTS
WARNING:
All return ducts must be secured to the furnace
with sheet metal screws. All return ducts must
be adequately sealed. When return air is provided
through the bottom of the unit, the joint between
the furnace and the return air plenum must be
air tight.
Return air and circulating air ducts must not be
connected to any other heat producing device
such as a fireplace insert, stove, etc. This may
result in fire, explosion, carbon monoxide
poisoning, personal injury, or property damage.
Return Air Connections
Air return to the furnace must have a minimum free area
opening that meets the minimum installation clearances
found on page 5. A return air grille for closet or alcove
installations is available. Acceptable installations with
return air entering through an opening in the floor, ceiling
of a closet, or alcove installation, must meet all of the
following requirements:
• The return air opening, regardless of its location, must
not be smaller than size specified on unit data label. If
located in the floor, the opening must be provided with
a means of preventing its inadvertent closure by flat
object(s) placed over the opening.
• A return air grille must be used on the furnace when
installed in a closet or alcove:
Upflow Alcove installations
– E7EM Models: Use a coil box with a solid door and
an upflow stand (
Figure 1 (page 5)). Part numbers
can be found in the Technical Specifications
Literature.
– E7EU Models: Use upflow stand.
Closet installations:
– All E7 Models: A louvered door must be added in
the closet door or above it for adequate air flow.
Downflow alcove installations:
– E7EM Models: A grille may be attached to the top
of the furnace and all paneling and trim flushed
to it. This installation provides an access door for
future installation of air conditioning or heat pump
coils on top of the furnace.
– E7ED models are for non-ducted return.
– E7EU Models can be used for ducted return.
• Materials located in return air duct system must have
a flame-spread classification of 200 or less.
• Noncombustible pans having 1” upturned flanges
must be located beneath openings in a floor-return
duct system.
Supply Air Connections
• Supply duct system must be designed for proper air
distribution. Static pressure measured externally to
furnace shall not exceed static pressure rating listed
on furnace nameplate.
• Duct system must be designed so that no supply
registers are located in duct system directly below the
furnace.
Filtering Methods - Downflow Furnaces
Non-Ducted Return Air
For unducted return air systems, either the optional grille
and frame assembly or the optional wall mount grille is
recommended.
• E7ED Models: Make sure there is an 18”x20” filter in
the top filter rack and an 18”x30” filter in the front filter
rack.
Without A/C or H/P uncased coil
• Use the filter supplied with the furnace. Make sure
the filter is installed mat side down between the filter
retainer and furnace top.
With A/C or H/P uncased coil
• Use the optional coil filters; the filter supplied with the
furnace is not used; REMOVE AND DISCARD THIS
FILTER.
With optional coil housing
• See coil cabinet instructions for specific filtering
methods.
Ducted Return Air
For ducted return air systems with air conditioners or
heat pumps, either providing an access panel in the duct
or using the optional coil cabinet is recommended. The
duct system must be properly sized to account for any
additional external static pressure produced from the
chosen filtering method.
NOTE: Install a filter with a minimum unrestricted medium
area that meets the application requirements of the furnace
in the duct above the coil that is accessible for monthly
cleaning or replacement by homeowner.
Filtering Methods - Upflow Furnaces
Non-Ducted Return Air
Furnaces may be installed with unducted or ducted return
air. For unducted systems it is recommended to use an
upflow stand for optimal performance.
Without optional upflow stand
• Install a filter with a minimum unrestricted medium area
of 324 in
2
below the coil cabinet/furnace assembly that
is accessible for monthly cleaning or replacement by
the homeowner.
With optional upflow stand
• Stand (Figure 1) will use filters provided with the unit.
Remove any filters in the furnace and follow proper
installation. See instructions supplied with the upflow
stand for additional details.
Ducted Return Air
For ducted systems with air conditioners or heat pumps,
the following optional equipment is recommended: coil
cabinet and upflow duct connector.