TemperZone OPA 970RLTB1FPQ Maintenance and service guide

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OPA 970RLTB1FPQ(-Z) (Econex)
Air Cooled Packaged Units - Reverse Cycle - R32
Installation & Maintenance
CONTENTS Page
1. GENERAL ..............................................................................1
2. INSTALL ATION ......................................................................2
3. REFRIGERATION SYSTEM...................................................2
4. WIRING ..................................................................................3
5. ECONOMISER .......................................................................3
6. START-UP PROCEDURE ......................................................4
7. O PER ATI O N ...........................................................................5
8. MAINTENANCE .....................................................................5
9. TROUBLESHOOTING ...........................................................6
10. WARRANTY .........................................................................6
APPENDIX I : UC8 PROTECTION FUNCTIONS.......................7
APPENDIX II: AIR HANDLING PERFORMANCE....................9
COMMISSIONING CHECK LIST .............................................10
1. GENERAL
Temperzone OPA Outdoor Air Cooled Packaged units.
Follow these instructions to ensure the optimum performance,
reliability and durability.
Units must be installed in accordance with all national and
regional regulations and bylaws. National Health and Safety
regulations must be followed to avoid personal injuries.
The appropriate local permits must be acquired and
adhered to.
Local regulations on maximum boundary noise need to
be considered when positioning the unit.
The accompanying ‘R32 Handling Ducted Packaged Units’
pamphlet forms part of these Installation & Maintenance
instructions.
!WARNING
These units use R32 refrigerant (Class A2L) which is mildly
ammable.
The system shall be installed, operated and stored in a well
ventilated space. If the refrigerant gas comes into contact with
re, a poisonous gas may occur. Be aware that R32 does not
contain an odour.
If indoors, the appliance shall be stored in a room away from
continuously operating sources known to cause ignition of R32
refrigerant (for example an operating gas appliance or operating
electric heater)
2. INSTALLATION
2.1 Clearances & Service Access
Refer to Specication Sheet supplied for minimum
clearances. If multiple units are to be placed side-by-side
then allow at least 2m between coil faces.
2.2 Mounting
The unit should be fastened to a rm at horizontal base
using the holes supplied in the mounting channels. When
the unit is being installed on a roof it is recommended that
the unit is installed on a substantial structure with vibration
isolating pads or mounts. If placed on the ground or
concrete pad, use rubber pads or mounts to give 20mm min.
ground clearance.
Flexible duct connections are recommended between the
supply and return ducts and the unit.
Unit is shipped with plastic wedges installed under the
compressors. Ensure these wedges are removed from
the compressor feet prior to starting the unit
(not required for operation).
003-000-301 08/23

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2.3 Economiser/Fresh Air Cowl Option
The Economiser cowl is supplied separately and must be
tted to the unit – usually after the unit is lifted in to place.
Screws and pre-drilled holes are provided. Ensure the top
of the cowl is tucked under the roof lip of the air conditioner
and that all joints are sealed with silicon sealant. There
must be at least 300mm clearance beneath the cowl once it
is tted in place.
2.4 Condensate Drains
The condensate drains should be ‘U’ trapped outside the
unit. The traps should have a vertical height of at least 100
mm. The drain lines should have a slope of at least 1 in 50
and must not be piped to a level above the unit drain pipe.
OPEN
DRAIN
MINIMUM
SLOPE
20 mm PER m
(1 IN 50)
100 mm
MINIMUM
200 mm
APPROX.
'U' TRAP
100 mm
APPROX.
VENT PIPE
FOR LONG
CONDENSATE
DRAIN RUNS
3. REFRIGERATION SYSTEM
3.1 General
Each OPA 970 has two refrigeration systems – one with a
variable speed inverter compressor; the other with a xed
speed compressor.
Each refrigeration system has been charged with R32
refrigerant; refer Specications document for amount.
3.2 Compressors
The compressors are inverter and xed speed scroll
type. The compressor lubricant is POE-46 (NXG5020
or equivalent). Note, this oil absorbs moisture quickly if
exposed to open air.
4. WIRING
4.1 Electrical Requirements
Electrical work must be done by a qualied electrician and
meet standard AS/NZS 3000.
! DANGER! LIVE ELECTRICAL CONNECTIONS. ISOLATE MAINS
POWER BEFORE WORKING ON UNIT. ONLY QUALIFIED PERSONS
WHO ARE COMPETENTLY TRAINED SHOULD PERFORM SERVICE AND
MAINTENANCE TASKS.
The unit must be wired directly from a distribution board
using an appropriately sized circuit breaker. The termination
point for the mains cable is in the electrical compartment. An
isolating switch is required, near but not on the unit.
Refer Appendix III (p.10) for cable entry hole locations and
recommended wiring paths.
4.2 Control options
OPA Econex units can be controlled using any of the
following options:
• TZT-100 wall thermostat (excludes dampers control)
• 24V AC and 0-10V signals from an external controller or
thermostat
• Remote on/off switch and/or time clock
• Modbus RTU serial communications over RS485
connection
• BACnet-IP serial communications over Ethernet
connection (with optional gateway module)
Standard reverse cycle units are suitable for use with
thermostats and controls with manual heating/cooling
selection or automatic change-over.
A unit wiring diagram is supplied alongside the electrical
board and in the Specications document.
4.3 TZT-100 wall thermostat
To connect the thermostat to the unit it is recommended
to use shielded twisted pair type cable, suitable for RS485
communications. Signals A and B should form one twisted
pair.
Note: The cable shield should connect to terminal ‘0V’ on
the UC8 controller only. Do not connect at both ends.
Connect the thermostat as follows:
TZT-100 Connection:
TB22M B
TB22T A
TB22B 0V
TB23T 12V
TB22B
B
A
24C
24
W6
PCLP1 TZT-100
OPA
Control
- shielded
twin twisted pair
4 core
(201-000-399)
Note: Capacity Staging. A TZT-100 must be congured for
single-stage operation, the default setting.
TZT-100 has its own DIP switches that must be set as
follows:
DIP switch 2 ON Equipment type = Heat Pump
DIP switch 3 OFF Equipment stages = One
DIP switch 4 ON Reverse cycle valve on = Heating
The UC8 master controls the staging of the compressors.
4.4 Communications format for TZT-100
Communications format must be set as per recommended
Modbus RTU:
• Baud rate (bd or br) 19200
• Data bits 8
• Parity Even
• Stop bits (Pa) 1
• TZT-100 address (Ad) 7
The procedure to check and adjust these settings is:
1. Press and hold the O/RIDE button until the display
shows the PIN
2. Use the UP & DOWN buttons to select PIN code 88:21,
then press O/RIDE in installer mode.
3. Use the O/RIDE and PROG buttons to cycle through the
various installer settings.
If necessary, refer TZT-100 User Manual for more detail.
4.5 Remote on/off
The UC8 has an input for a remote on/off function on
terminal ‘On’, signal return is terminal ‘0V’. When used the
remote on/off terminals should connect to a voltage-free
relay contact. When not used the remote on/off terminals
should be shorted (‘bridged’).
4.6 Capacity control
OPA Econex units offer the following capacity control
options:
• Automatic control when the unit connects to the TZT-100.
• 24VAC xed and 0-10V inverter compressor control signals
• 0-10V indoor fan control signal.
• Control by a building management system via Modbus
RTU or BACnet-IP serial communications.

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4.7 Unit Controller (UC8)
The unit’s UC8 controller receives requests such as ‘Unit
On/Off’, ‘Start compressors’, ‘Activate HEAT (Reverse
Cycle)’ and transfer the requests to the outputs after
enforcing safety timers.
Figure 4. UC8 Controller
The Unit Controller provides several system protection
functions. These are covered in Appendix I (p.9).
For additional information, refer to the UC8 Controller label
on the unit or www.temperzone.biz for operation & fault
diagnostics information; model search ‘UC8’.
References available:
UC8 Operation Manual : Air-to-Air Units
UC8 Fault & Display Messages (as per unit label)
UC8 Quick Reference and Operation Fault Diagnosis
UC8 Troubleshooting Guide
UC8 Modbus Communications
UC8 BACnet Communications
UC8 Master-Slave Connection
4.8 Control using switched and 0-10V signals
An external controller that provides 12/24V ac/dc switched
signals or has a set of voltage-free relay contacts should be
connected as per the diagram below. If no fan/compressor
capacity control signals, then link UC8 terminals ‘VF’ and ‘5’
and ‘VC’ and ‘12’.
Figure 5. BMS connection
BMS /
external controller
Capacity
0-10V
HIGH
MEDIUM
LOW
COMP
HEAT
24V ac/dc
or
12V ac/dc*
24V ac COM
or
0V
0-10V
0V
Fan
HIGH IN
MED IN
LOW IN
FAN 0-10V
COMP 0-10V
COMP ON
HEAT ON
COM
OPA Terminals
*If using the unit’s
internal 12V dc
from UC8, add
this loop
0V
COM
Comp.
4.9 ControlviaModbusRTUcommunications
OPA Econex units can be fully monitored and controlled via
Modbus RTU serial communications.
The following is typical for most installations:
• Set DIP switches 11 and 12 to OFF on all UC8 controllers.
• Connect BMS terminal A / TX+ to terminal A1 on the
UC8 controller via terminal block shown.
• Connect BMS terminal B / TX- to terminal B1 on the
UC8 controller via terminal block shown.
Multiple OPA units can be daisy-chained together.
For detailed information about monitoring and control
via Modbus RTU refer to document ‘UC8 Modbus
communications’, available at www.temperzone.biz (model
search ‘UC8’) or .com website.
4.10SettingtheUC8Modbusdeviceaddress
To view or change the Modbus device address of a UC8
follow these steps:
• Power up the unit but leave the compressors off.
• Hold down the SW3 pushbutton on the UC8 circuit board
until the display shows:
‘0’ [release] ‘1’ short press to ‘2,’ [long press] A,
[long press]
• The display will show the current Modbus device address.
The factory default address is ‘44’. [Short press] the button
to select higher numbers, for example press once to
change the address to 45, press twice for address 46 and
so forth. [Long press] to save the chosen address. After
address 99 the number returns back to 1.
• The controller returns to the default state (– ●).
4.11 BMS – BACnet
A BACnet connection is availble using Babel Buster 3.
For information regarding using BACnet commands, please
ask Temperzone.
5. ECONOMISER OPTION
The Economiser package that is factory tted consists of
two opposed blade dampers, one for the fresh air and the
other for the return air and complete with individual damper
motors controllable from a 0 – 10V dc signal. The package
also includes a fresh air cowl (weatherhood) assembly that
is supplied as a separate item for tting on site.
It is important that the installation instructions for the tting
of the fresh air cowl are followed otherwise it is possible
some water ingress from rain could occur. The top ange of
the cowl must be tucked under the top panel lip.
The damper control (by others) should be wired such
that the return air damper will close proportionally as the
fresh air damper opens proportionally and vice versa. The
fresh air damper’s adjustable stop can be set such that
it does not close 100%; many installations may require a
minimum fresh air introduction of 10 – 15% and the stop
may be set on site to facilitate this. Set the economiser
Fresh Air Damper motor ‘stop’ to the equivalent negative
static pressure as with F/A damper closed. This is to
ensure the air ow volume remains constant and does not
dramatically increase when introducing fresh air. Failure to
set the correct ‘stop’ position could result in rain/moisture
entrainment in the incoming fresh air resulting in water
deposited inside the unit.
As previously mentioned a 0 – 10V dc control signal is
required to drive the dampers open and closed. This could
be from a BMS or a temperature/humidity controller.
It is recommended that control is by Enthalpy (ie by a
LCD Display
Push button

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combination of dry and wet bulb temperatures) so that free
cooling is used without adding any heat load to the building.
Control by dry bulb temperature alone is not recommended
as often, even though the outdoor dry bulb temperature may
be lower than that of the space, the total heat content of the
air can be higher thereby adding heat load in the form of
moisture content to the space.
If dry bulb temperature is used as the control method the
temperature must be set several degrees lower than the
space temperature to reduce the possibility of extra heat
load being introduced.
An Air Quality (CO2) sensor (supplied by others) can be
used to proportionally control the fresh and return air
dampers (via the control system).
In all situations the UC8 Unit Controller will allow the
compressors to operate with the economiser fresh air
damper open providing the refrigeration system is not
compromised.
The compressor(s) could be stopped from operating by
normal protection devices such as low suction temperature/
pressure or indoor coil frost protection and too many trips
of either fault could lead to a lock out of the compressor(s)
operation. Should this occur then a review of the control
settings may be necessary.
6. START-UP PROCEDURE
6.1 Before starting the compressor
1. Before working on the unit remove mains power from
the unit by opening the mains isolating switch.
2. Remove the shipping wedges from beneath each
compressor. Check that each compressor is securely
mounted.
3. Check the thermostat and/or other controls are
correctly wired to the unit.
4. Check tightness of electrical connections.
5. Check air lters have been correctly installed. (Filters
must be installed before starting the unit.)
6. Check that all indoor fan motors can freely rotate.
7. Apply mains power to the unit by closing the mains
isolating switch.
8. Check the supply voltage between each phase and
neutral.
9. Air Balance the building's ducting system using
an experienced HVAC technician. This will require
temporary isolation of the compressors using the
internal circiuit breakers, and running the fan only.
(Refer 6.3 for fan speed considerations)
10. Apply mains power to the unit by closing the mains
isolating switch.
11. Once Air Balancing is complete, power OFF the unit
and reset the compressor circuit breakers.
12. BEFORE starting the compressors a four hour delay
period is required to allow the crankcase heaters to
drive any liquid refrigerant out of the compressor oil.
Mains power must be switched on during this four hour
delay period.
6.2 Commissioning
After the four hour delay period has expired (see step 10 in
section 6.1) complete the following procedure. You can use
the Commissioning Sheet (refer p.10) to help you.
1. Place the UC8 controller in commissioning mode by
pressing and holding the SW3 push button (see Fig. 4)
until the display shows:
‘0’ [release] ‘1’ [long press] ‘t’; [short press] repeat
to nd ‘c’, then [long press] to select.
This Commissioning mode ‘c’ reduces the waiting times
at start-up and between cycles.for the next half
hour, or until the controller is reset by removing
power.
2. Start compressor in Cooling mode.
3. Check the outdoor fan motor runs smoothly.
Note: The outdoor fan does not necessarily start rotating
immediately after the compressor is started. The fans
may run-on for a short period after the compressor
stops.
Outdoor fan stops during outdoor coil de-ice cycles.
4. Measure the current draw on each phase to the
compressor motor and to each fan motor. Check the
readings against the specied values in the wiring
diagram or specication sheet.
5. The display and pushbutton on the UC8 can be used
to check temperatures and pressures. Short presses
on the pushbutton cycles through the available
options. Table1 on page 8 shows, in sequence, what
information is available – with examples.
Alternatively use a set of pressure gauges suitable for
R32 refrigerant.
!WARNING
Under no circumstances shall potential sources of
ignition be used in the searching for or detection of
refrigerant leaks. If a leak is suspected, all naked ames
shall be removed/extinguished.
If a leakage of refrigerant is found which requires
brazing, all of the refrigerant shall be recovered from the
system, or isolated (by means of shut-off valves) in a
part of the system remote from the leak.
6. Repeat steps 2 to 5 for each compressor.
7. Test operation of the compressors when operating in
heating mode.
8. Check for desired supply air ow rate at each outlet (if
air balancing has not been completed).
9. Touch up any outdoor unit paintwork damage to prevent
corrosion.
10. Sign the check label on the Electrical Box cover.
6.3 Commissioningofvariablespeed(EC)indoorplugfan
A unit equipped with variable speed (EC) indoor plug fan
allows adjustment of the fan speeds to obtain the desired
indoor supply airows.
Using TZT-100 option
If the unit is controlled with a temperzone TZT-100 wall
thermostat then adjustments are made as follows:
i. Ensure the compressor is off and the thermostat or BMS
does not request for the compressor to start. The UC8
display should show a ashing dot (●).
ii. To adjust the fan High speed press and hold down the
SW3 push button on the UC8 circuit board until the
display shows:
‘0’ [release] ‘1’ [long press] ‘t’; [short press] repeat
to nd ‘H’, then [long press] to select.
iii. The fan will start and run at High speed. The display
shows the fan control voltage for the High
speed setting; factory default value is 8.0V.
iv. Each following press on the SW3 push button increases
the indoor fan control voltage in steps of 0.5V, up to a
maximum of 10.0V. Pressing the push button again when
value 10.0 is shown returns the fan control voltage down
to the minimum value of 3.0V and back up again.
v. When the desired setting for high fan speed is displayed,
[long press] to select and save. The controller then exits
the menu and the fan stops.

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vi. To adjust the fan Low speed hold down the SW3 push
button on the circuit board until the display shows:
‘0’ [release] ‘1’ [long press] ‘t’; [short press] repeat
to nd ‘L’, then [long press] to select.
The fan will start and run at the Low speed setting. The
factory default value is 5.0V.
vii. Repeat steps (iv) and (v) to adjust the fan Low speed
setting. The minimum control voltage for Low speed is
1V and the maximum control voltage for Low speed is
8V. (Note: A ‘low’ control voltage of less than 2V is not
recommended.) If ‘low’ is set higher than ‘high’, the ‘high’
is made equal to ‘low’.
viii Check if the High speed airow is to specication (refer
Note below)
Using Alternative Thermostats
Follow same procedure as for TZT-100.
Note:
If fan speed selections are different from the factory default
values then the procedure above must be carried out for the
UC8 controller in the unit.
It is allowed to make the control voltages for low and high
fan speed equal. This makes the indoor fan act as a xed
speed fan.
It is allowed to control the indoor fan speed by an external
source, independent of the UC8 controller. It is then the
responsibility of the system-designer and installer to ensure
proper and safe operation of the indoor fan, and the system
as a whole, under all operating conditions.
Setting the indoor fan speed too low can bring risk of frost
forming on the indoor coil with potential nuisance frost
protection trips on cooling, possibly even unit lock-out, and/
or HP trips on heating.
Setting the indoor fan speed too high can bring a risk of any
condensation being sucked off the ns of the indoor coil
off the ns of the indoor coil and into the supply air duct.
Water could then start leaking from the supply air vents and
diffusers and corrosion of ducting may occur.
Setting the indoor fan speed too high can also bring a risk
of ‘over-condensing’ (when the unit is heating) which in turn
could cause the unit to perform more outdoor coil de-ice
cycles than necessary.
Refer Appendix II Air Handling graphs for min./max.
airows.
7. OPERATION
7.1 Safety timers
The UC8 receives control signals and transfers the signals
to the outputs after enforcing safety timers and other
protection functions. If the compressor is held off, or held
on, by a safety timer then the display shows message ‘H-O-
L-d’.
Normal durations of safety timers are:
• Minimum off time 3 minutes
• Minimum run time 1.5 minutes
• Min. cycle time 6 minutes (up to 10 compressor
starts per hour)
• Min. mode change-over time
10 minutes (cooling to heating or
vice-versa)
7.2 VariableCapacity
The OPA unit is equipped with a single variable capacity
compressor (inverter scroll type) and one xed capacity
compressor. The inverter compressor operating capacity is
16%–100% using 1.6V–10V control voltages. Fixed speed
compressor operate at 100%.
At any time, when operating conditions dictate, system
protection functions can restrict unit operating capacity.
When a capacity signal is presented that is lower than the
minimum capacity (for example 0V on input ‘VC’) then the
compressor operates on minimum duty.
If a unit operates on low capacity for extended periods
then the unit may periodically perform oil ush cycles.
Under such operating conditions compressor lubricating oil
may slowly settle in parts of the refrigeration system other
than the compressor. Oil ush cycles help to return the
lubricating oil to the compressor. During an oil ush cycle
compressor speed is increased for a duration of 1 minute.
Variable capacity indoor air fan – Refer Section 5.3
Note:
Setting the indoor fan speed too low can bring risk of frost
forming on the indoor coil with potential nuisance frost
protection trips on cooling, possibly even unit lock-out, and/
or HP trips on heating.
Setting the indoor fan speed too high can bring a risk of
blowing moisture off the ns of the indoor coil and into the
supply air duct. Water could then start leaking from the
supply air grilles and corrosion of ducting may occur.
Setting the indoor fan speed too high can also bring a risk
of ‘over-condensing’ (when the unit is heating) which in turn
could cause the unit to perform more outdoor coil de-ice
cycles than necessary.
Refer Appendix iV for indoor airow range.
Outdoor fans do not necessarily start rotating immediately
after the compressor is started. The fans may run-on for a
short period after the compressor stops.
The indoor fan will reduce speed if in heating mode and the
condensing temperature is too low to automatically allow
the condenser coil to warm up. The fan speed may also
slightly reduce when in Latent Cooling mode, if this option is
enabled.
8. MAINTENANCE
!
WARNING! HAZARDOUS VOLTAGE. ENSURE ALL POWER SUPPLIES
ARE ISOLATED BEFORE PERFORMING MAINTENANCE. FAILURE TO
ISOLATE POWER CAN LEAD TO SERIOUS INJURY.
8.1 Monthly
1. Check air lters and vacuum, wash clean or replace as
necessary.
2. Check condensate drain for free drainage.
3. Check compressor compartment for oil stains indicating
refrigerant leaks.
!WARNING
Under no circumstances shall potential sources of
ignition be used in the searching for or detection of
refrigerant leaks. If a leak is suspected, all naked ames
shall be removed/extinguished.
If a leakage of refrigerant is found which requires brazing,
all of the refrigerant shall be recovered from the system.
4. Check system operating pressures via each UC8
controller or using a Temperzone Wi Service Utility
(WSU); pn 201-000-700; refer Appendix I.
8.2 Six Monthly
1. Check the tightness of electrical connections.
2. Check for signs of corrosion on electrical connections in
high salt atmospheres; replace where necessary.

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3. Check the tightness of all fan motor mountings
4. Check system operating pressures via each UC8
controller or using a Temperzone Wi Service Utility
(WSU); refer Appendix I.
5. Check condensate drain for free drainage.
8.3 Yearly
1. Check all refrigerant piping for chang and vibration.
2. Check air supply at all diffusers
3. Check for excessive noise and vibration and correct
as necessary.
4. Check for insulation and duct damage and repair
as necessary.
5. Check system operating pressures via each UC8
controller, or using a Temperzone Wi Service Utility
(WSU); refer Appendix I.
7. Remove lint and dust accumulation from outdoor
coil ns with soft brush or low pressure water spray. In
corrosive environments, the checking and cleaning
frequency should be increased.
8. Touch up any paintwork damage to prevent corrosion.
9. TROUBLESHOOTING
9.1 Roomtemperaturevariessignicantlyfromitssetting
• Unit may have been incorrectly sized for the building.
• Drafts from wrongly placed supply air diffusers or from the
back of the wall plaque could be affecting the temperature
sensor built into the wall plaque.
• Poor air circulation in the room can cause incorrect
temperature readings.
9.2 Air conditioner does not seem to deliver the heating
when most needed
• Heating capacity at design conditions may be incorrect.
As the outside temperature falls, heat losses through the
walls, oor and ceiling increase.
• Check the unit’s brochure for information on the minimum/
maximum operating temperatures.
• When heating, units have de-icing cycles built-in to remove
ice on the outdoor coils. This usually means reversing
the cycle on some, but not all systems at once, for a few
minutes. Heating may be slightly reduced at this time, but
usually not noticable.
9.3 Inanewbuilding,whydoesittakesomedaysbefore
theairconditioningheatpumpunitseemstowork
properly
• Many new buildings, especially a commercial buildings,
have a large amount of concrete and other structural
materials that are generally cold and full of moisture. This
is most evident in winter when trying to heat the building
from outdoor ambient condition, ie a Cold Start.
9.4 Unitisleakingwater
• Check the drain trap/vent/slope.
• Water carry-over: Reduce the maximum fan speed.
Refer Appendix II for indoor airow range.
• Check fresh air damper is not opened by BMS when
raining outside
9.5 Air conditioner runs excessively – the temperature
remains too hot in summer or too cold in winter
• Windows or doors may be opened to non conditioned
areas.
• Keep doors to unconditioned areas closed.
• Leaves, papers or other items blocking air ow over the
outdoor unit coil.
• Location of wall controller or remote temperature sensor is
incorrect.
• Check for air leaks in supply or return air ductwork.
9.6 Unit displays an error code:
• Refer to UC8 Controller label on the unit for
operation & fault diagnostics information or visit
www.temperzone.biz; model search ‘UC8 Controller’.
10. WARRANTY
Please refer to the separate warranty document supplied with
the unit, or visit www.temperzone.com for details.
Australia:
[e-mail]
[e-mail]
Telephone: [phone]
New Zealand:
[e-mail]
Telephone: 0800 TZWARRANTY (899 2777)

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APPENDIX I
UC8 PROTECTION FUNCTIONS
Each OPA Econex unit utilises up to four UC8 Controllers,
one for each refrigeration system. The UC8 controllers
receive requests from the Master Controller such as ‘Unit
On/Off’, ‘Start compressors’, ‘Activate HEAT (Reverse
Cycle)’ and transfer the requests to the outputs after
enforcing safety timers.
Each UC8 implements system protection functions such as
indoor coil frost, extreme high and low pressures, rapid on-
off cycling of the compressors, loss of refrigerant and more.
The following applies to all protection functions except
where otherwise indicated:
Unit operating capacity may automatically be reduced
before a protection function is activated. Such a reduction
may be sufcient to prevent an actual trip from occurring.
When a compressor is stopped by a protection function it is
held off for a period of 3 minutes, after which it is allowed to
restart (provided the cause of the trip has cleared).
When a protection function is active and when a unit is
locked out the alarm relay output “FLT” is active.
For more information about protection functions and
troubleshooting, refer to document “UC8 Troubleshooting”,
available at www.temperzone.biz website; model search
‘UC8’.
1 High pressure protection (HP)
OPA Econex units are tted with high pressure transducers
connected to UC8 input HPT. A compressor is switched
off when the discharge line pressure reading exceeds
approx. 4350 kPa.
The display shows the letters ‘HP’ when protection
is active.
2 Low pressure protection (LP)
OPA Econex units are tted with low pressure transducers
connected to UC8 input LPT. A compressor is switched
off when the suction line pressure reading falls
below 130 kPa (inverter) / 140 kPa (xed speed).
The display shows the letters ‘LP’ when protection
is active.
3 Indoor coil frost protection
When the unit is cooling the evaporating temperature in the
indoor coil should remain above -8°C. If this temperature
falls below -8°C then ice (frost) likely will form on the
indoor coil. If the low temperature persists for longer than 6
minutes then the protection function activates.
When indoor coil frost protection is
activated the compressor is stopped for
6 minutes, after which it is allowed to
restart.
4 High discharge line temperature protection
The controller monitors the compressor discharge line
temperature via a sensor connected to input ‘DL’ (red wires).
The compressor is stopped when:
• The temperature rises above 115°C for longer than
15. minutes.
• The temperature rises above 125°C (immediate action).
The display shows the message ‘Hi-t’ when
protection is active.
5 High discharge superheat protection
Discharge superheat is dened as the difference between
the compressor discharge gas temperature and the
condensing temperature. When this temperature differential
becomes very high it is an indication that the compressor
is being starved of refrigerant gas. Common reasons for
this could be a lack of refrigerant (under-charged or loss-
of-charge) or a problem with the expansion device (for
example a stuck accurator or loose wiring to an EEV).
The protection is activated when R32 discharge superheat
exceeds 60K for longer than 30 minutes.
The display shows the message ‘Hi-
dSH’ when protection is active.
6 Low discharge superheat protection
Discharge superheat is dened as the difference between
the compressor discharge gas temperature and the
condensing temperature. When this temperature differential
stays very low it can be an indication that the compressor
is being ooded with liquid refrigerant. Common reasons
for this could be an excess of refrigerant (over-charged) or
a problem with the expansion device (for example a stuck
accurator or loose wiring to an EEV).
The protection is activated when discharge superheat
remains below the threshold for longer than 15 minutes.
The threshold varies linearly from 0K at standard mode
minimum capacity (40%) to 10K at nominal capacity (100%).
This protection function is disabled when a compressor
operates at less than standard mode minimum capacity
(< 40%).
The threshold for a variable speed compressor operated in
boost mode (capacity above 100%) is xed at 10K.
The display shows the message ‘LO-
dSH’ when protection is active.
7 High evaporation temperature / high suction line
temperature protection
When the unit has a low pressure transducer connected to
the compressor suction line then the controller calculates
the evaporating temperature from the suction line pressure
reading. If the unit does not have a low pressure transducer
then the controller nds the evaporating temperature
via a coil temperature sensor (input IC when the unit is
cooling, input OC when the unit is heating, yellow wires).
Additionally the controller monitors the compressor suction
line temperature via a sensor connected to input ‘SL’ (white
wires).
The protection function stops the compressor when:
• The evaporating temperature remains above 27.5°C for
longer than 15 minutes.
• The suction line temperature remains above 30°C for
longer than 15 minutes.
The display shows the message ‘Hi-SL’
when protection is active.
LCD Display
Push button

- 8 -
8 Lock-out
Each protection function has a trip counter. A trip counter
is reset to 0 whenever the compressor run request is
removed. Any trip that has occurred more than 12 hours
ago is removed from the trip count. For some protection
functions, when the trip counter reaches value 3 (i.e. three
consecutive trips occur) then the unit is “locked out”.
When a unit is locked out the compressor is not allowed to
start. Lock-out is designed to protect the compressor from
repeatedly starting when a serious fault exists that requires
the attention of a service technician.
The display shows the code of the fault that caused the
lock-out condition.
A unit that is locked out can be unlocked using any one of
the following methods:
• Remove mains power from the unit for at least 3 seconds,
then restore power.
• Issue an ‘unlock’ command via Modbus RTU serial
communications.
• Reset the controller via Modbus RTU serial
communications.
9 Safety timers
Each UC8 slave controller receives control signals and
transfers the signals to the outputs after enforcing safety
timers and other protection functions. If the compressor is
held off, or held on, by a safety timer then the
display shows message ‘H-O-L-d’.
Normal durations of safety timers are:
• Minimum off time 3 minutes
• Minimum run time 1.5 minutes
• Min. cycle time 6 minutes (up to 10 compressor
starts per hour)
• Min. mode change-over time
10 minutes (cooling to heating or
vice-versa)
Note:
If a unit operates on low capacity for extended periods then
the unit may periodically perform oil ush cycles. Under
such operating conditions compressor lubricating oil may
slowly settle in parts of the refrigeration system other than
the compressor; oil ush cycles help to return the lubricating
oil to the compressor. During an oil ush cycle compressor
capacity is increased to a certain minimum. The duration of
an oil ush cycle is 1 minute.

- 9 -
APPENDIX II
AIR HANDLING PERFORMANCE
Note: Airows are for a dry coil. Refer Airow Selection below.
As lters thickness varies, the fan air ows given are for units installed without lters.
No allowance for Reheat coil option.
OPA 970RLTB1FPQ
NB Air Flow Selection
If air returning to the indoor coil is regularly expected to be above 50% relative humidity then the coil
face velocity should be limited to 2.5m/s or less (refer air ow graph above)
Consideration must be given to selecting a airow and coil face velocity that avoids water carry-over
problems, ie in high humidity (tropical/subtropical) conditions or when heavily moisture laden fresh air
is introduced.
A unit running below or above allowable air ow range can damage components and cause
unnecessary unit protection 'tripping'.
l/s - Pa
3000 4000 5000 6000 7000
0
100
200
300
AIR FLOW (l/s)
AVAILABLE EXTERNAL PRESSURE (Pa)
2.5 m/s Face Velocity
400
500
2000 NOMINAL
8V
7V
6V
10V
l/s-kW
3000 4000 5000 6000 7000
1
2
3
4
AIR FLOW (l/s)
POWER INPUT (kW)
5
6
2000
7V
6V
10V
8V

- 10 -
APPENDIX III
CONNECTION WIRING PATHS
400V 3 phase
power supply wiring
conduit, from mains via
isolation switch, up to Ø50.
Anchor rails are provided.
IMPORTANT!
Don’t run low and high
voltage wiring in parallel;
separate where possible.
BMS comm’s wire,
up to Ø25 (option).
DO NOT secure to refrigeration
piping unless it is insulated.

INSTALLER TO COMPLETE
COMMISSIONING CHECK LIST
Site Name/address: ..........................................................................................................................................................................
Installing Company ...................................................................................................... Date: ..........................................................
Serviceman: ............................................................................................................... Tel: ............................................................
Model ..................................................................... Serial No..................................... Site Ref. ....................................................
Unit mounted level? Y / N Supply voltage checked? Y / N
Temperzone recommended drain trap tted? Y / N External electrical isolator tted? Y / N
Water drains tested okay? (panels on, fan running) Y / N Indoor Plug fan set voltage or l/s V l/s
Does unit have adequate safe access? Y / N Are temperature controller’s parameters set? Y / N
All electrical terminals are tight? Y / N Checked for excessive noise & vibration of unit? Y / N
Return air lters tted? Y / N Has client had controls demo? Y / N
Removed compressor shipping wedges? Y / N Electrical Certicate Of Compliance issued? Y / N
Refrigeration leak checked? Y / N If installed indoors, is there adequate ventilation to
disperse any refrigerant in the unlikely event of a
leak.
Y / N
Is air ow set and balanced? Y / N Economiser temp/RH sensor correctly positioned? Y / N
Thermostat type: BMS / TZT-100 / Other? (name):
MarkUC8dipswitchpositionswithan'X'
SW1 SW2
12345678 9 (1) 10 (2) 11 (3) 12 (4) 13 (5) 14 (6) 15 (7) 16 (8)
On On
Off Off
RecordthefollowingUC8monitoredconditionsusingpushbuttonSW3(repeattoscrollthroughlist).
IMPORTANT: Digital compressors must be operating at 100% for at least 10 minutes when taking these readings.
System 1 System 2
Low Pressure: SLP kPa kPa Outdoor Ambient temperature: °C
Evap temperature: Et °C °C Indoor Return air temperature: °C
Suction Line temperature: SLt °C °C Indoor Supply air temperature: °C
Suction Superheat: SSH K K Indoor fan amps : A
Discharge Line Pressure: dLP kPa kPa Fresh Air introduced : %
Condensing temperature: Ct °C °C Compressor 1 amps : A
Discharge Line temperature: dLt °C °C Compressor 2 amps : A
Discharge Superheat: dSH K K Compressor 3 amps : A
De-ice Sensor temperature: ICEt °C °C Compressor 4 amps : A
Required Capacity: CAP % %
Expansion Valve 1: EE1 % %
Expansion Valve 2: EE2 % %
Low Pressure: SLP kPa kPa Outdoor Ambient temperature: °C
Evaporating temperature: Et °C °C Indoor Return air temperature: °C
Suction Line temperature: SLt °C °C Indoor Supply air temperature: °C
Suction Superheat: SSH K K Indoor fan amps : A
Discharge Line Pressure: dLP kPa kPa Fresh Air introduced : %
Condensing temperature: Ct °C °C Compressor 1 amps : A
Discharge Line temperature: dLt °C °C Compressor 2 amps : A
Discharge Superheat: dSH K K Compressor 3 amps : A
De-ice Sensor temperature: ICEt °C °C Compressor 4 amps : A
Required Capacity: CAP % %
Expansion Valve 1: EE1 % %
Expansion Valve 2: EE2 % %
NOTE: This document to be kept with the unit. Failure to provide this completed page on request by Temperzone
may affect unit warranty.
COOLING CYCLEHEATING CYCLE

08/23© temperzone ltd 2023
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AS/NZS
ISO 9001:
2015
www.temperzone.com
Auckland
Head Ofce
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Private Bag 93303, Otahuhu
New Zealand
Phone: [phone]
Email: [e-mail]
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NSW 2147, Australia
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Phone: [phone]
Email: [e-mail]
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Phone: [phone]
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Phone: [phone]
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Hamilton
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Materials and specications are subject to change without notice due to the manufacturer’s ongoing research and development programme.