Daikin UAA-ST3M User manual

OPERATION
MANUAL
AIR -COOLED CHILLER
(SINGLE SCREW COMPRESSOR)
UAA-ST3M
OM-UAA-0620(1)-DAIKIN
Part Number:C08019049338

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TABLE OF CONTENTS
TABLE OF CONTENTS II
1. INTRODUCTION 3
1.1 General 3
2. DEFINITION 5
3. ABOUT SAFETY 7
4. CONTROL PANEL 8
4.1 System Architecture 8
4.2 Control Panel Layout 9
4.3 Controller features 10
4.4 Main controller 11
5. OPERATING THE CONTROL SYSTEM 13
5.1 Start/Stop Unit 13
5.2 Parameter Viewing and setting 14
6. UNIT PARAMETERS 32
6.1 Unit Setpoints 32
7. TROUBLESHOOTING GUIDE 40
7.1 Startup Troubleshooting Guide 40
7.2 Alarm Troubleshooting Guide 42
7.3 Alarm Clearing 73
7.4 Alarm Log 73
8. BAS INTERFACE 74
8.1 General 74
8.2 Modbus protocol 74
8.3 BACNEt protocol 78

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1. INTRODUCTION
1.1 General
This manual provides setup, operating, troubleshooting and maintenance information for the DAIKIN
Air Cooled Single Screw Chillers listed below with 1 and 2 circuits using MicroTech III Controller.
HAZARD IDENTIFICATION INFORMATION
⚠DANGER
Dangers indicate a hazardous situation which will result in death or serious injury if not avoided.
⚠WARNING
Warnings indicate potentially hazardous situations, which can result in property damage, severe
personal injury, or death if not avoided.
⚠CAUTION
Cautions indicate potentially hazardous situations, which can result in personal injury or equipment
damage if not avoided.
ER

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Software Version:
This manual covers units with Software Version: MHS010V1.31
The unit’s software version number can be viewed by selecting the “About chiller” menu item
accessible without password.
⚠CAUTION
•Electric shock hazard: can cause personal injury or equipment damage. This equipment must
be properly grounded. Connections to, and service of, the MicroTech III control panel must
be performed only by personnel who are knowledgeable in the operation of this equipment.
•Static sensitive components. A static discharge while handling electronic circuit boards can
cause damage to the components. Discharge any static electrical charge by touching the bare
metal inside the control panel before performing any service work. Never unplug any cables,
circuit board terminal blocks, or power plugs while power is applied to the panel.
! WARNIN ! CAUTION
NOTICE
This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used
in accordance with this instruction manual, can cause interference to radio communications.
Operation of this equipment in a residential area can cause harmful interference, in which case the
user will be required to correct the interference at the user’s own expense. Daikin disclaims any
liability resulting from any interference or for the correction thereof.

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2. DEFINITION
Active Setpoint
The active setpoint is the parameter setting in effect at any given moment. This variation can occur on
setpoints that can be altered during normal operation. Resetting the chilled water leaving temperature
setpoint by one of several methods such as return water temperature is an example.
Active Capacity Limit
The active capacity setpoint is the setting in effect at any given moment. Any one of several external
inputs can limit a compressor’s capacity below its maximum value.
Dead Band
The dead band is a set of values associated with a setpoint such that a change in the variable occurring
within the dead band causes no action from the controller. For example, if a temperature setpoint is
44F and it has a dead band of 0.2 degrees F, nothing will happen until the measured temperature is less
than 43.8F or more than 44.2F.
LWT
Chilled / Evaporator leaving water temperature.
EWT
Chilled / Evaporator entering water temperature.
Discharge Superheat
Discharge superheat is calculated using the following equation:
Discharge Superheat = Discharge Temperature –Condenser Saturated Temperature
Suction Superheat (SSH)
SSH is calculated for each circuit using the following equation:
SSH = Suction Temperature –Evaporator Saturated Temperature
Evaporator Approach
The evaporator approach is calculated for each circuit. The equation is as follows:
Evaporator Approach = LWT –Evaporator Saturated Temperature.
EXV
Electronic expansion valve, used to control the flow of refrigerant to the evaporator, controlled by the
circuit microprocessor.
Unload Evaporator Low Pressure Setpoint
The kPa suction pressure setting at which the controller will unload the compressor to maintain the
minimum setting.
HMI
Operator Interface Touch Screen, one screen per unit provides operating data visually and
accommodates setpoint entry.

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Stage Up / Stage Down Delta-T
Staging is the act of starting or stopping a compressor or fan when another is still operating. Startup
and Stop is the act of starting the first compressor or fan and stopping the last compressor or fan. The
Delta-T is the “dead band” on either side the setpoint in which no action is taken.
Stage Up Delay
The time delay from the start of the first compressor to the start of the second.

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3. ABOUT SAFETY
Electrical installation
⚠CAUTION
•All electrical connections to the machine must be carried out in compliance
with laws and regulations in force.
•All installation, operating and maintenance activities must be carried out by
qualified personnel.
•Please refer to the specific wiring diagram for the machine that you have
purchased, and which was sent with the unit.
•Should the wiring diagram not come with the machine, please contact your
dealer for further action.
•Use copper conductors only. Failure to use copper conductors could cause
overheating or corrosion at the connection points and damages the unit.
•To avoid interference, all control wires must be installed separately from the
power wires. Use separate electrical conduits for this purpose.
•Before servicing the machine in any way, open the general disconnecting
switch on the machine's main power supply.
•When the machine is off, but the disconnector switch is in the closed position,
unused circuits are live as well.
•Never open the terminal board box of the compressors before having opened
the unit's general disconnecting switch.
•In installations with power supply lines longer than 50 meters, inductive
coupling between phases and between phase and earth generates significant
electromagnetic field.
•In order to limit these phenomena, it is good practice to lay out the phase
wires symmetrically, as described in the figure:
•Chiller unit compressors are single-direction rotation compressors and can be
damaged if rotated in the wrong direction. For this reason, proper phasing of
electrical power is important. Terminal block indicator (R, S, T). R=L1, S=L2, T=L3

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4. CONTROL PANEL
4.1 System Architecture
The MicroTech III control system for air cooled single screw chillers consists of a main unit controller
with several extension I/O modules attached depending on the chiller size and configuration. Up to
two optional BAS communication modules may be included on request.
The overall controls architecture uses the following:
•One Microtech III main controller
•I/O extension modules as needed depending on the configuration of the unit
•Optional BAS interface as selected
Model
Controller Quantity
POL687.7
POL945
POL965
POL94U
UAA105–UAA220
1
1
1
1
UAA245-UAA450
1
1
2
2
BAS
Interface
(Modbus,
Bacnet)
MicroTech III Main
Controller POL687
I/O Extension
POL965
(Sys 1)
I/O
Extension
POL94U
(Sys 1)
I/O
Extension
POL94U
(Sys 2)
I/O Extension
POL945
I/O Extension
POL965
(Sys 2)

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4.2 Control Panel Layout
Item
Function
Description
1
Q0 (Unit Switch)
OFF
Turn OFF the unit
ON
Turn ON the unit
2
Q1 (1#SYS SW)
OFF
Turn OFF System 1
ON
Turn ON System 1
3
Q2 (2#SYS SW)
OFF
Turn OFF System 2
ON
Turn ON System 2
4
CM1
Indicating working current for 1#SYS Compressor
5
CM2
Indicating working current for 2#SYS Compressor