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Fig. 2 --- Unit Leveling Tolerances
Refer to Accessory Roof Curb Installation Instructions for
additional information, as required.
SLAB MOUNT (HORIZONTAL UNITS ONLY)
Provide a level concrete slab that extends a minimum of 6 in.
beyond the unit cabinet. Install a gravel apron in front of the
condenser coil air inlet to prevent grass and foliage from
obstructing airflow.
NOTE: Horizontal units may be installed on a roof curb, if
required.
ALTERNATE UNIT SUPPORT
When the curb or adapter cannot be used, support unit with
sleepers using unit curb or adapter support area. If sleepers cannot
be used, support the long sides of the unit with a minimum of 3
equally spaced 4-in. x 4-in. pads on each side.
STEP 2 —FIELD- - FABRICATED DUCTWORK
Secure all ducts to the roof curb and building structure on vertical
discharge units. Do not connect ductwork to the unit. For
horizontal applications, attach field-supplied flanges to the
horizontal discharge openings and attach all ductwork to the
flanges. Insulate and weatherproof all external ductwork, joints,
and roof openings with counter flashing and mastic in accordance
with applicable codes.
Ducts passing through an unconditioned space must be insulated
and covered with a vapor barrier.
If a plenum return is used on a vertical unit, duct the return
through the roof deck to comply with applicable fire codes.
A minimum clearance is not required around ductwork. Cabinet
return-air static pressure (a negative condition) should not exceed
0.35 in. wg with economizer, or 0.45 in. wg without economizer.
STEP 3 —INSTALL CONDENSATE DRAIN LINE
AND EXTERNAL TRAP
Condensate drain connections are located at the bottom and side
of the unit. Unit discharge connections do not determine the use
of drain connections; either drain connection can be used with
vertical or horizontal discharge units.
When using the standard side drain connection, make sure the
plug (red) in the alternate bottom connection is tight before
installing the unit.
To use the bottom drain connection for a roof curb installation,
relocate the factory-installed plug (red) from the bottom
connection to the side connection. The center drain plug looks
MAXIMUM ALLOWABLE
DIFFERENCE (in.)
A-B
B-C
A-C
0.5
1.0
1.0
C06002
like a star connection, but can be removed with a
drive extension. (See Fig. 3.) Complete the piping for the
condensate drain and external trap after the unit is in place.
All units must have an external trap for condensate drainage.
Install a trap at least 4 in. deep and protect it against freeze-up. If
drain line is installed downstream from the external trap, pitch the
line away from the 50HJQ unit at
a pipe size smaller than the unit connection (
CONDENSATE PAN (SIDE VIEW)
HORIZONTAL
DRAIN OUTLET
NOTE: Drain plug is shown in factory-installed position.
Fig. 3 --- Condensate Drain Connection
(Side View)
NOTE: Trap should be deep enough to offset maximum unit static
difference. A 4-in. trap is recommended.
Fig. 4 --- Condensate Drain Piping Details
STEP 4 —RIG AND PLACE UNIT
Inspect the unit for transportation damage, and file any claim with
the transportation agency. Keep the unit upright and do not drop.
Spreader bars are not required if top crating is left on the unit, and
rollers may be used to move the unit across a roof. Level by using
the unit frame as a reference. See Table 1 and 2 and Fig. 5 for
additional information. Operating weight is shown in Table 1 and
2 and Fig. 5.
Lifting holes are provided in the base rails as shown in Fig. 5 and
6. Refer to rigging instructions on the unit.
3
1
/
-in. socket
2
1
/
in. per ft of run. Do not use
4
3
/
-in.). (See Fig. 4.)
4
DRAIN PLUG
C06003
C06004
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