Carrier SINGLE PACKAGE ROOFTOP UNITS 48PG20-28 - Manual

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
PC 111 Catalog No. 534-80211 Printed in U.S.A. Form 48PG-10SI Pg 1 9-05 Replaces: New Book 1 4
Tab 1a 6a
Installation, Start-Up and Service Instructions
CONTENTS
Page
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . 1,2
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-17
Step 1 — Provide Unit Support . . . . . . . . . . . . . . . . . . . . . . . . .2
•
ROOF CURB
• ALTERNATE UNIT SUPPORT
• SLAB MOUNT
Step 2 — Remove Shipping Rails . . . . . . . . . . . . . . . . . . . . . . .2
Step 3 — Rig and Place Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
•
POSITIONING
• ROOF MOUNT
• INSTALLATION ONTO CURB
Step 4 — Field Fabricate Ductwork . . . . . . . . . . . . . . . . . . . . .9
Step 5 — Make Unit Duct Connections. . . . . . . . . . . . . . . . . .9
•
VERTICAL CONFIGURATION
• HORIZONTAL APPLICATIONS
Step 6 — Install Flue Hood and Inlet Hood . . . . . . . . . . . . 10
Step 7 — Trap Condensate Drain . . . . . . . . . . . . . . . . . . . . . 10
Step 8 — Install Gas Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Step 9 — Make Electrical Connections. . . . . . . . . . . . . . . . .11
•
FIELD POWER SUPPLY
• FIELD CONTROL WIRING
Step 10 — Install Outdoor-Air Hood. . . . . . . . . . . . . . . . . . . 12
•
MANUAL DAMPER ASSEMBLY
Step 11 — Position Optional Power
Exhaust or Barometric Relief Damper Hood . . . . . . . . . 16
Step 12 — Non-Fused Disconnect . . . . . . . . . . . . . . . . . . . . 16
Step 13 — Install All Accessories . . . . . . . . . . . . . . . . . . . . . 16
PRE-START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
START-UP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18-45
Unit Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Compressor Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Refrigerant Service Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Crankcase Heater(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Compressor Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Internal Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Subcooler Heat Exchanger (SHX) . . . . . . . . . . . . . . . . . . . . . 18
Evaporator Fan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Condenser Fans and Motors . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Return-Air Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Outdoor-Air Inlet Screens. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Gas Heat. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Optional EconoMi$er IV. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Operating Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
SERVICE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46-57
Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Manual Outdoor Air Damper . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Economizer Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Evaporator Fan Service and Replacement . . . . . . . . . . . . 48
Evaporator Fan Performance Adjustment . . . . . . . . . . . . . 48
Evaporator Fan Belt Tension Adjustment . . . . . . . . . . . . . 48
Condenser Fan Adjustment. . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Verify Sensor Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Economizer Operation During Power Failure. . . . . . . . . . 49
Evacuation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Refrigerant Charge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Gas Valve Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
High Altitude. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Main Burners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Filter Drier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Protective Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Relief Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Page
Control Circuit, 24-V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Replacement Parts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Diagnostic LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57-61
Unit Troubleshooting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
EconoMi$er IV Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . 60
Phase Loss Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
UNIT 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 the basic maintenance
functions of cleaning coils and filters and replacing filters. All
other operations should be performed by trained service per-
sonnel. When working on air-conditioning equipment, observe
precautions in the literature, tags and labels attached to the unit,
and other safety precautions that may 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.
Before performing service or maintenance operations on
unit, turn off main power switch to unit. Electrical shock
could cause personal injury.
Puron (R-410A) refrigerant systems operate at higher pres-
sures than standard R-22 systems. Do not use R-22 service
equipment or components on Puron refrigerant equipment.
If service equipment is not rated for Puron refrigerant,
equipment damage or personal injury may result.
1. Improper installation, adjustment, alteration, service,
or maintenance can cause property damage, personal
injury, or loss of life. Refer to the User’s Information
Manual provided with this unit for more details.
2. Do not store or use gasoline or other flammable
vapors and liquids in the vicinity of this or any other
appliance.
What to do if you smell gas:
1. DO NOT try to light any appliance.
2. DO NOT touch any electrical switch, or use any
phone in your building.
3. IMMEDIATELY call your gas supplier from a neigh-
bor’s phone. Follow the gas supplier’s instructions.
4. If you cannot reach your gas supplier, call the fire
department.
48PG20-28
Single Package Rooftop Units
Electric Cooling/Gas Heating with
Electromechanical Controls and PURON® (R-410A) Refrigerant