Carrier 48TF004-007 User Manual
Installation, start-up, and service instructions
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
PC 111
Catalog No. 534-80000
Printed in U.S.A.
Form 48TF-1SI
Pg 1
8-00
Replaces: New
Book 1
4
Tab
1a 6a
Installation, Start-Up, and
Service Instructions
CONTENTS
Page
SAFETY CONSIDERATIONS
. . . . . . . . . . . . . . . . . . . . . . 1
INSTALLATION
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-35
Step 1 — Provide Unit Support
. . . . . . . . . . . . . . . . . . . 1
• ROOF CURB
• SLAB MOUNT
Step 2 — Field Fabricate Ductwork
. . . . . . . . . . . . . . . 2
Step 3 — Install External Trap for Condensate
Drain
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Step 4 — Rig and Place Unit
. . . . . . . . . . . . . . . . . . . . . 2
• POSITIONING
Step 5 — Install Flue Hood
. . . . . . . . . . . . . . . . . . . . . . . 4
Step 6 — Install Gas Piping
. . . . . . . . . . . . . . . . . . . . . . 4
Step 7 — Make Electrical Connections
. . . . . . . . . . . 8
• FIELD POWER SUPPLY
• FIELD CONTROL WIRING
• HEAT ANTICIPATOR SETTINGS
Step 8 — Make Outdoor-Air Adjustments
and Install Outdoor-Air Hood
. . . . . . . . . . . . . . . . . . 11
• MANUAL OUTDOOR-AIR DAMPER
• OPTIONAL DURABLADE ECONOMIZER
• OPTIONAL ECONOMI$ER
Step 9 — Adjust Evaporator-Fan Speed
. . . . . . . . . 19
• DIRECT-DRIVE MOTORS
• BELT-DRIVE MOTORS
START-UP
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36-38
SERVICE
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38-43
TROUBLESHOOTING
. . . . . . . . . . . . . . . . . . . . . . . . . 44-49
START-UP CHECKLIST
. . . . . . . . . . . . . . . . . . . . . . . . CL-1
SAFETY CONSIDERATIONS
Installation and servicing of air-conditioning equipment can
be hazardous due to system pressure and electrical compo-
nents. Only trained and qualified service personnel should
install, repair, or service air-conditioning equipment.
Untrained personnel can perform basic maintenance func-
tions of cleaning coils and filters and replacing filters. All other
operations should be performed by trained service personnel.
When working on air-conditioning equipment, observe precau-
tions in the literature, tags and labels attached to the unit, and
other safety precautions that apply.
Follow all safety codes. Wear safety glasses and work
gloves. Use quenching cloth for unbrazing operations. Have
fire extinguishers available for all brazing operations.
INSTALLATION
Unit is shipped in the vertical duct configuration. To convert
to horizontal configuration, remove screws from side duct
opening covers and remove covers. Using the same screws, in-
stall covers on vertical duct openings with the insulation-side
down. Seals around duct openings must be tight. See Fig. 1.
Confirm before installation of unit that voltage, amperage
and circuit protection requirements listed on unit data plate
agree with power supply provided.
Step 1 — Provide Unit Support
ROOF CURB — Assemble and install accessory roof curb in
accordance with instructions shipped with curb. See Fig. 2. In-
stall insulation, cant strips, roofing felt, and counter flashing as
shown. Ductwork must be attached to curb, not to the unit. The
accessory thru-the-bottom power and gas connection package
must be installed before the unit is set on the roof curb. If field-
installed (thru-the-roof curb) gas connections are desired, use
factory-supplied
3
/
4
-in. pipe coupling and gas plate assembly to
mount the thru-the-roof curb connection to the roof curb. Gas
connections and power connections to the unit must be field in-
stalled after the unit is installed on the roof curb.
If electric and control wiring is to be routed through the
basepan, attach the accessory thru-the-bottom service connec-
tions to the basepan in accordance with the accessory installa-
tion instructions.
Disconnect gas piping from unit when leak
testing at pressure greater than
1
/
2
psig.
Pressures greater than
1
/
2
psig will cause
gas valve damage resulting in hazardous
condition. If gas valve is subjected to pres-
sure greater than
1
/
2
psig, it must be
replaced before use. When pressure testing
field-supplied gas piping at pressures of
1
/
2
psig or less, a unit connected to such
piping must be isolated by manually closing
the gas valve.
Before performing service or maintenance operations on
unit, turn off main power switch to unit and install a lock-
out tag. Electrical shock could cause personal injury.
IMPORTANT: The gasketing of the unit to the roof curb
is critical for a watertight seal. Install gasket supplied
with the roof curb as shown in Fig. 2. Improperly
applied gasket can result in air leaks and poor unit
performance.
48TF004-007
Single-Package Rooftop
Heating/Cooling Units