Carrier 50HJ008-014, Installation, Start-Up And Service Instructions Manual, Page: 3 / 40

A minimum clearance to combustibles is not required around
ductwork on vertical discharge units. On horizontal dis-
charge units, a minimum clearance of 1 in. is required for
the first 12 in. of ductwork. Cabinet return-air static should
not exceed −0.35 in. wg with Durablade or Parablade econo-
mizer, or −0.45 in. wg without economizer.
Step 3 — Install Condensate Drain Line and
External Trap —
Condensate drain connections are lo-
cated at the bottom and end of the unit. Unit discharge con-
nections do not determine the use of drain connections; ei-
ther drain connection can be used in vertical or horizontal
applications.
When using the standard end drain connection, make sure
the plug 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 from the bot-
tom connection to the end connection. See Fig. 3. The pip-
ing for the condensate drain and external trap can be com-
pleted after the unit is in place.
All units must have an external trap for condensate drain-
age. Install a trap at least 4-in. deep and protect against freeze-
up. See Fig. 4. If drain line is installed downstream from the
external trap, pitch the line away from the 50HJ unit at 1 in.
per 10 ft of run. Do not use a pipe size smaller than the unit
connection.
Step 4 — Rig and Place Unit —
Inspect unit for trans-
portation damage. File any claim with transportation agency.
Keep unit upright and do not drop. Spreader bars are not
required if top crating is left on unit. Rollers may
be used to move unit across a roof. Level by using
unit frame as a reference. See Table 1 and Fig. 5 for addi-
tional information. Operating weight is shown in Table 1 and
Fig. 5.
Lifting holes are provided in base rails as shown in
Fig. 5 and 6. Refer to rigging instructions on unit.
POSITIONING — Maintain clearance around and above unit
to provide proper airflow and service access. See
Fig. 6.
Position unit on roof curb so that the following clearances
are maintained: 1 ⁄
4
-in. clearance between roof curb and base
rails on each side and in front of unit; 1 5 ⁄
32
-in. clearance be-
tween roof curb and rear of unit (see Fig. 1, section C-C).
Do not install unit in an indoor location. Do not locate
unit air inlet near exhaust vents or other sources of contami-
nated air.
Although unit is weatherproof, guard against water from
higher level runoff and overhangs.
After unit is in position, remove polyethylene shipping wrap-
per and rigging skid.
MAXIMUM ALLOWABLE DIFFERENCE
(in.)
A-B B-C A-C
0.5 1.0 1.0
Fig. 2 — Unit Leveling Tolerance
Fig. 3 — Condensate Drain Location
NOTE: Trap should be deep enough to offset maximum unit static
difference. A 4-in. trap is recommended.
Fig. 4 — External Trap Condensate Drain
3