Dunham-Bush ACDX - User Manual

Screw Type Air-Cooled Packages
Installation, Operation, and Maintenance Instructions
Form 6193A
ACDX/AUDX
TABLE OF CONTENTS
DESCRIPTION ........................................................................................................... PAGE NO.
Introduction & Product Identification .......................................................................................... 1
Physical Specifications .............................................................................................................. 2
Inspection .................................................................................................................................. 3
Rigging and Moving ................................................................................................................... 3
Location and Mounting .............................................................................................................. 3
Piping connections...............................................................................................................3 & 4
Multiple Chiller Water Connections ......................................................................................4 & 5
AUDX Condensing Unit Piping................................................................................................... 4
Electrical Connections ............................................................................................................... 6
ACDX Operation & Start-up .................................................................................................6 & 7
Maintenance .............................................................................................................................. 7
Slide Valve Unloading Operation................................................................................................ 8
Low Ambient Operation ............................................................................................................. 9
Fan Position Numbers .............................................................................................................. 10
Fan Cycling Sequence ............................................................................................................. 11
ACDX Sequence of Operation ................................................................................................. 12
Electrical Controls ........................................................................................................ 13, 14, 15
Field Control Wiring .........................................................................................................15 & 16
Star-Delta Starting Operation .................................................................................................. 16
Microcomputer Controller............................................................................................. 16 thru 23
Typical Wiring Diagram and Electrical Data .................................................................24 thru 30
Evaporator Water Pressure Drop ............................................................................................. 31
ACDX Refrigerant Piping Schematic ....................................................................................... 32
Condenser Clearance Requirements....................................................................................... 33
Rigging Instructions ................................................................................................................. 34
Point Loading ...................................................................................................................... 35-40
Trouble Shooting Guide ........................................................................................................... 41
Start-up Check List .................................................................................................................. 42

Summary

INTRODUCTION

PRODUCT IDENTIFICATION

Identifies the unit model, control method, and voltage.

PHYSICAL SPECIFICATIONS

GENERAL UNIT INFORMATION

INSPECTION

Outlines procedures for checking equipment upon delivery for damage or discrepancies.

LOCATION & MOUNTING

Details requirements for unit placement, ensuring proper airflow and support.

PIPING CONNECTIONS

Covers chilled water piping and connections for the unit.

Water Connections, Chilled Water Piping

Details chilled water piping installation, flow switch requirements, and freeze prevention.

ELECTRICAL CONNECTIONS

SYSTEM START UP

Details the process of requesting a start-up representative and initial system checks.

MAINTENANCE

COMPRESSOR

Covers checking oil levels and recommended oil types for the compressor.

SLIDE VALVE UNLOADING SYSTEM

LOW AMBIENT OPERATION

Cooler Freeze Protection - Low Ambient

Addresses freeze protection measures for the chiller in low ambient conditions.

FAN OPERATION AND CONTROL

ACDX FAN CYCLING SEQUENCE CHART

Provides a chart detailing fan operation based on model and circuit.

SEQUENCE OF OPERATION

Stage 1 Starting

Details the process for the first stage of compressor start-up and fan control.

SAFETY CONTROLS

ELECTRICAL CONTROLS

FIELD CONTROL WIRING

MICROCOMPUTER CONTROLLER

General Description

Introduces the NC25 microcomputer system and its components.

Operation of LCD Display NC25-4

Guides on operating the NC25 microcomputer's LCD display for data access.

CONTROL SYSTEM OPERATION

To Display data from the menu

Instructions on accessing various data types via the menu system.

SETPOINT AND CALIBRATION PROCEDURES

To Alter Setpoint Data

Guide on changing setpoint values after authorization.

Capacity Control of Screw Compressors

Automatic Control

Explains how the computer automatically adjusts compressor capacity based on load.

OPERATIONAL SAFETY FEATURES

Low Pressure Safety

Safety feature that locks off compressors on low suction pressure.

High Pressure Safety

Safety feature that locks off compressors on high discharge pressure.

Sensor Alarm Shutdown

TYPICAL POWER WIRING (ACDX120 A)

TYPICAL CONTROL WIRING (ACDX120 A)

ACDX ELECTRICAL DATA

WATER SIDE PRESSURE DROP

ACDX 040-255 PIPING SCHEMATIC

ACDX;AUDX CONDENSER CLEARANCE

RIGGING INSTRUCTIONS

TROUBLESHOOTING GUIDE

CHILLER UNIT WILL NOT START

Lists common causes and remedies for a unit failing to start.

COMPRESSOR CUTS OUT ON LOW PRESSURE SAFETY CONTROL

Identifies causes for compressor shutdown due to low pressure.

START-UP CHECK LIST

Dunham-Bush ACDX Specifications

General

Brand	Dunham-Bush
Model	ACDX
Category	Chiller
Language	English