Mounting On Roof Curb; Venting; Duct Connections; Gas Piping - Trane GRAA Installation Operation & Maintenance

3
Support m ust clear return
a i r openin g a nd fi t Ins i de
b ase rai l flan ge.
See Figures 4 & 13
for this dimension.
Support must fit
inside base rail
f lang es.
MOUNTING ON ROOF CURB
Assemble and install roof curb per Roof Curb
Installation Instructions. See Figures 4 & 13 for roof
opening sizes, distance between openings and unit
relationship to roof curb.
VENTINGt
All venting installations shall be in accordance with
the latest edition of Part 7 , "Venting of Equipment", of
the National Fuel Gas Code, ANSI Z223.1-1992 (or
the latest edition), or applicable provisions of local
building codes.
The Natural Vented u nits'... are equipped with a vent
cap which is designed for n atural draft venting. Air for
combustion enters the base of the vent cap through
a protective grill and products of combustion are dis-
charged at the upper section of the vent cap. t Th i s
ve nt c a p i s sh i pped in a separate carton and
s hould be installed per the Venting section of the
Outdo or
Rooftop Gas- F i red
Duct Fu r na ce
In sta llati on and Service Manual .
The Power Vented unit has a induced draft venting
system. The combustion air inlet and products of
combustion discharge louvers are located in the
upper section of the Duct Furnace side access
panel. Never locate these units in an area where the
flue products discharge outlet may be directed at any
fresh air vents. See the Outdoor Rooftop Gas-Fired
Duct Furnace Installation and Service M anual for
installation and servicing requirements.
DUCT CONNECTIONS
All ductwork must be properly supported so that no
strain is put on the unit. Do not alter or bend the dis-
charge duct flanges supplied on your furnace/air
handler.
Ducts connected to units which do not have either a
blower section or a supply plenum must have a
removable access panel in the duct which is con-
nected to a duct furnace. The duct openings shall be
accessible when the unit is installed in service, and
shall be of such size that smoke or reflected light
may be observed inside the casing to indicate the
presence of leaks in the heating element. The covers
for the panels shall be attached in such a manner as
to prevent leaks. Ducts exposed to the outdoors must
be insulated and sealed to prevent water from either
the unit or building through the duct.
If a single, double or triple duct furnace only unit is
connected to a return air duct, or any other inlet air
restriction, the appliance shall be installed on the
positive pressure side of the air circulating blower.
When connecting return air duct to Standard or High
CFM cabinets, attach duct to return air opening
flange when no dampers are used. Otherwise, if
dampers are used, attach return air duct around col-
lar at bottom of damper assembly. Also refer to the
Submittal Data Sheets specified for your unit.
When connecting supply air duct to Supply Plenum,
attach duct to supply air opening flange when no
dampers are used. Otherwise, if dampers are used,
attach supply air duct around collar at bottom of
damper assembly. Refer to the Figure 13.
GAS PIPING tt
All gas piping must be installed in accordance with
local codes. It is required that a ground union be
installed adjacent to the gas valve of each duct fur-
nace, and a ground union be installed just external of
each duct furnace for unit servicing. On vertical runs,
a drip leg should be provided upstream of any con-
trol manifold. A gas shutoff valve should be, or may
be required by local codes, installed upstream of the
external ground union for each duct furnace. A 1/8
inch N.P.T. plugged tapping, accessible for test
gauge connection, must be installed immediately
upstream of the unit gas supply connection.
tt For complete Gas Piping installation, see
Outdoor
Rooftop Gas-Fired Duct Furnace
Installation and Service Manual.
It is recommended that the gas piping not be
installed through the bottom of the duct furnace bot-
tom panel. If piping must penetrate the duct furnace
bottom panel, it must be sealed to prevent water
leakage.
Gas piping must be installed to allow for removal of
burner drawer for unit maintenance. Refer to Figure 2.
-6-