Carrier 50HG014-028 installation instructions Contents, Safety Considerations

50HG014-028 Single Package Rooftop Units Electric Cooling with Electric Heat Option

Installation Instructions

CONTENTS

Page

SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . 1

INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-23

Step 1 — Provide Unit Support . . . . . . . . . . . . . . . . . . . 1

•ROOF CURB

•ALTERNATE UNIT SUPPORT

Step 2 — Remove Shipping Rails . . . . . . . . . . . . . . . . 3 Step 3 — Rig and Place Unit . . . . . . . . . . . . . . . . . . . . . 3

•POSITIONING

•ROOF MOUNT

•INSTALLATION ONTO CURB

Step 4 — Field Fabricate Ductwork. . . . . . . . . . . . . . . 8 Step 5 — Make Unit Duct Connections . . . . . . . . . . . 8 Step 6 — Trap Condensate Drain . . . . . . . . . . . . . . . . . 9 Step 7 — Make Electrical Connections . . . . . . . . . . . 9

•FIELD POWER SUPPLY

•FIELD CONTROL WIRING

Step 8 — Install Outdoor-Air Hood . . . . . . . . . . . . . . 20

Step 9 — Position Optional Power Exhaust

or Barometric Relief Damper Hood. . . . . . . . . . . . 22 Step 10 — Non-Fused Disconnect. . . . . . . . . . . . . . . 22 Step 11 — Install All Accessories . . . . . . . . . . . . . . . 23

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 replacing filters. All other operations should be performed by trained service personnel. 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.

IMPORTANT: Units have high ambient operating lim- its. If limits are exceeded, the units will automatically lock the compressor out of operation. Manual reset will be required to restart the compressor.

INSTALLATION

Step 1 — Provide Unit Support

ROOF CURB — Assemble or install accessory roof curb in accordance with instructions shipped with this accessory. See Fig. 1. Install insulation, cant strips, roofing, and counter flash- ing as shown. Ductwork can be installed to roof curb before unit is set in place. Curb must be level. This is necessary to permit unit drain to function properly. Unit leveling tolerance is

±1/16 in. per linear ft in any direction. Refer to Accessory Roof Curb Installation Instructions for additional information as required. When accessory roof curb is used, unit may be installed on class A, B, or C roof covering material.

IMPORTANT: The gasketing of the unit to the roof curb is critical for a watertight seal. Install gasket with the roof curb as shown in Fig. 1. Improperly applied gasket can also result in air leaks and poor unit performance.

ALTERNATE UNIT SUPPORT — When a curb cannot be used, install unit on a noncombustible surface. Support unit with sleepers, using unit curb support area. If sleepers cannot be used, support long sides of unit with a minimum of 3 equal- ly spaced 4-in. x 4-in. pads on each side.

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.

Book	1	4	PC 111	Catalog No. 535-00092	Printed in U.S.A.	Form 50HG-7SI	Pg 1	11-03	Replaces: 50HG-3SI
Tab	1b	6b