Carrier 50EW Air Conditioner User Manual


 
Installation, Start-Up and
Service Instructions
CONTENTS
Page
SAFETY CONSIDERATIONS .................. 1
INSTALLATION ............................ 1-31
Step 1 Provide Unit Support .............. 1
ROOF CURB
ALTERNATE UNIT SUPPORT
Step 2 Rig and Place Unit ................. 8
POSITIONING
ROOF MOUNT
Step 3 Field Fabricate Ductwork ...........11
Step 4 Make Unit Duct Connections .......11
Step5—TrapCondensate Drain .............11
Step 6 Controls Options ..................12
CONSTANT VOLUME APPLICATIONS
VARIABLE AIR VOLUME (VAV)
APPLICATIONS
Step 7 Make Electrical Connections .......15
POWER WIRING
FIELD POWER SUPPLY
FIELD CONTROL WIRING
Step 8 Make Outdoor-Air Inlet
Adjustments ...............................25
ECONOMIZER
ECONOMIZER SETTINGS
Step 9 Position Power Exhaust/
Barometric Relief Damper Hood .............29
Step 10 Install Accessories ...............30
START-UP ................................32-42
SERVICE ..................................42-45
TROUBLESHOOTING ......................46-51
START-UP CHECKLIST ...............CL-1, CL-2
SAFETY CONSIDERATIONS
Installation and servicing of air-conditioning equipment
can be hazardous due to system pressure and electrical com-
ponents. 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 per-
sonnel. When working on air-conditioning equipment, ob-
serve 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 ex-
tinguishers 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 READ BEFORE INSTALLING
IMPORTANT: Due to upgrades in unit control soft-
ware and hardware, units produced currently are slightly
different than original design units. The unit control
software (which has changed) is designated with a sticker
on the unit control board, chip U8 (the large chip in
the center of the board), which states the software Ver-
sion number. Version 1.0 is the original version. Ver-
sion 2.0 is the current version. Differences in instal-
lation, configuration, and start-up procedures in this
manual will be identified by Version number.
INSTALLATION
Step 1 Provide Unit Support
All panels must be in place when rigging. Unit is not
designed for handling by fork truck.
ROOF CURB Assemble and install accessory roof curb
in accordance with instructions shipped with the curb. Ac-
cessory roof curb and information required to field fabricate
a roof curb or horizontal adapter are shown in Fig. 1 and 2.
Install insulation, cant strips, roofing, and counter flashing
as shown. Ductwork can be secured to roof curb before unit
is set in place.
IMPORTANT: The gasketing of the unit to the roof
curb is critical for a leak-proof seal. Install gasket sup-
plied with the roof curb as shown in Fig. 1. Improp-
erly applied gasket can result in air leaks and poor unit
performance.
Curb should be level. This is necessary to permit unit drain
to function properly. Unit leveling tolerance is shown in
Fig 1 and 2. Refer to Accessory Roof Curb Installation In-
structions for additional information as required. When ac-
cessory roof curb is used, unit may be installed on class A,
B, or C roof covering material.
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 long
sides of unit (refer to Fig. 3-6) with a minimum number of
equally spaced 4-in. x 4-in. pads as follows:
50EJ,EK,EW,EY024-034 units require 3 pads on each side;
50EJ,EK,EW,EY038-048 require 4 pads on each side. Unit
may sag if supported by corners only.
50EJ,EK,EW,EY024-048
Single-Package Rooftop Units
Electric Cooling with Electric Heat Option
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book 1
Tab 1b
PC 111 Catalog No. 535-006 Printed in U.S.A. Form 50E-3SI Pg 1 8-96 Replaces: 50E-1SI