nvent SpectraCool G520846G Series User manual

© 2020 nVent 89101404
Rev. M P/N 89101400
SPECTRACOOL
Air Conditioner
G52 460V Model
INSTRUCTION MANUAL

© 2020 nVent 89101404
- 2 -
NOTE: Some of the information in this manual may not apply if a special unit was ordered. If additional
drawings for a special unit are necessary, they have been inserted. Contact nVent Equipment Protection
if further information is required.
WARRANTY AND RETURN POLICY
https://hoffman.nvent.com/en/hoffman/warranty-information
TABLE OF CONTENTS
WARRANTY AND RETURN POLICY................................................................................................................................................................................................... 2
RECEIVING THE AIR CONDITIONER.................................................................................................................................................................................................. 3
HANDLING AND TESTING THE AIR CONDITIONER......................................................................................................................................................................... 3
HOW TO READ MODEL NUMBERS.................................................................................................................................................................................................... 3
TECHNICAL INFORMATION............................................................................................................................................................................................................... 4
Sequence of Operation.............................................................................................................................................................................................................. 4
Heating............................................................................................................................................................................................................................... 4
Cooling ............................................................................................................................................................................................................................... 4
Standard and Optional Component Operation........................................................................................................................................................................ 4
Thermostat ........................................................................................................................................................................................................................ 4
Remote Access Control (optional) .................................................................................................................................................................................. 4
Head Pressure Control...................................................................................................................................................................................................... 4
Contactor ........................................................................................................................................................................................................................... 4
Overload............................................................................................................................................................................................................................. 4
Phase Monitor ................................................................................................................................................................................................................... 5
460V to 230V Transformer............................................................................................................................................................................................... 5
230V to 10V Transformer (optional)................................................................................................................................................................................ 5
a230V to 24V Transformer and Relay (optional)............................................................................................................................................................ 5
Schematics and Wiring Diagrams for Thermostat Control .................................................................................................................................................... 6
G52 Generic Schematic With Thermostats (actual unit options may vary)................................................................................................................. 6
G52 Generic Wire Diagram With Thermostats (actual unit options may vary)............................................................................................................ 7
INSTALLATION INSTRUCTIONS With Thermostats......................................................................................................................................................................... 8
INSTALLATION INSTRUCTIONS WITH REMOTE ACCESS CONTROL............................................................................................................................................ 8
DIMENSIONAL DRAWINGS .............................................................................................................................................................................................................. 10
8000 BTU/Hr. With Thermostats ............................................................................................................................................................................................ 10
12000 BTU/Hr. With Thermostats .......................................................................................................................................................................................... 10
8000 BTU/Hr. With Thermostats and Heat............................................................................................................................................................................ 11
12000 BTU/Hr. With Thermostats and Heat.......................................................................................................................................................................... 11
REMOTE ACCESS CONTROL (optional).......................................................................................................................................................................................... 12
Introduction .............................................................................................................................................................................................................................. 12
Energizing the Controller ......................................................................................................................................................................................................... 12
Control Status Indication......................................................................................................................................................................................................... 12
Displaying and Changing Program Variables ........................................................................................................................................................................ 13
Operating Parameters.............................................................................................................................................................................................................. 13
Alarm Parameters.................................................................................................................................................................................................................... 13
Displaying Temperature Sensor #2 ........................................................................................................................................................................................ 13
Compressor Restart Time Delay............................................................................................................................................................................................. 13
Alarm Output Contact.............................................................................................................................................................................................................. 13
Alarm Input Connection........................................................................................................................................................................................................... 14
Alarm Condition Display.......................................................................................................................................................................................................... 14
Air Conditioner Unit Communication Features...................................................................................................................................................................... 14
USB Communication....................................................................................................................................................................................................... 14
Ethernet Communication................................................................................................................................................................................................ 14
Using the PC Interface Tool..................................................................................................................................................................................................... 15
USB Communication Mode............................................................................................................................................................................................ 15
Ethernet Communication Mode..................................................................................................................................................................................... 16
Remote Access Control Pin-out.............................................................................................................................................................................................. 17
Schematic and Wiring Diagram for Remote Access Control............................................................................................................................................... 18
G52 Generic Schematic With Remote Access Control (actual unit options may vary) ............................................................................................ 18
G52 Generic Wire Diagram With Remote Access Control (actual unit options may vary) ....................................................................................... 19
DIMENSIONAL DRAWINGS .............................................................................................................................................................................................................. 20
G52 Generic Model Drawing With Remote Access Control ................................................................................................................................................. 20
MAINTENANCE................................................................................................................................................................................................................................. 21
Compressor.............................................................................................................................................................................................................................. 21
Inlet Air Filter............................................................................................................................................................................................................................. 21
How To Remove, Clean or Install a New Inlet Air Filter......................................................................................................................................................... 21
Condenser and Evaporator Air Movers .................................................................................................................................................................................. 22
Refrigerant Loss....................................................................................................................................................................................................................... 22
F-GAS INFORMATION....................................................................................................................................................................................................................... 22
Refrigerant Properties Chart (R 134a).................................................................................................................................................................................... 23
Functional Data ........................................................................................................................................................................................................................ 23
8000 BTU/Hr. Unit Characteristics ......................................................................................................................................................................................... 24
12000 BTU/Hr. Unit Characteristics ....................................................................................................................................................................................... 25
SERVICE DATA................................................................................................................................................................................................................................... 26
Components List With Thermostat ........................................................................................................................................................................................ 26
Components List With Remote Access Control.................................................................................................................................................................... 27
TROUBLE SHOOTING ....................................................................................................................................................................................................................... 28
Basic Air Conditioning Trouble Shooting Check List - Thermostat Version........................................................................................................................ 28
Symptoms and Possible Causes - Thermostat Version....................................................................................................................................................... 29
Basic Air Conditioning Trouble Shooting Check List - Remote Access Control Version ................................................................................................... 30
Symptoms and Possible Causes - Remote Access Control Version................................................................................................................................... 31

© 2020 nVent
89101404 - 3 -
RECEIVING THE AIR CONDITIONER
Inspect the air conditioner. Check for concealed damage that may have occurred during shipment. Look for dents,
scratches, loose assemblies, evidence of oil, etc. Damage evident upon receipt should be noted on the freight bill.
Damage should be brought to the attention of the delivering carrier -- NOT to nVent Equipment Protection -- within
15 days of delivery. Save the carton and packing material and request an inspection. Then le a claim with the
delivering carrier.
nVent Equipment Protection cannot accept responsibility for freight damages; however, we will assist you in any
way possible.
HANDLING AND TESTING THE AIR CONDITIONER
If the air conditioner has been in a horizontal position, be certain it is placed in an upright, vertical or mounting
position for a minimum of ve (5) minutes before operating.
Do not attempt to operate the air conditioner while it is horizontal
or on its side, back or front. The refrigeration compressor is lled
with lubricating oil. This will cause permanent damage to the air
conditioner and also voids the warranty.
CAUTION
TEST FOR FUNCTIONALITY BEFORE MOUNTING THE AIR CONDITIONER TO THE ENCLOSURE.
Refer to the nameplate for proper electrical current requirements, and then wire the unit to a properly grounded
power supply using copper conductors only. Power supply wiring should be restrained after eld installation to
ensure no contact with internal fan. Minimum circuit ampacity should be at least 125% of the amperage shown
on the unit nameplate. No other equipment should be connected to this circuit to prevent overloading
Immediately after applying power, the evaporator blower (enclosure air) should start running. Operate the
air conditioner with the compressor running for ve (5) to ten (10) minutes. You will need to set the cooling
thermostat or controller setpoint below the ambient temperature to operate the compressor.
Condenser air temperatures should be warmer than normal room temperatures within a few minutes after the
condenser impellers start.
See Sequence of Operation on page 4 for specics on how the unit operates when powered up.
HOW TO READ MODEL NUMBERS
G52 12 4 6 G150
12345
1. Identies the type/family of air conditioner and the approximate height (i.e. G52 = Global family
about 52 inch high).
2. This is the air conditioner’s listed capacity in BTU/Hr. at rated conditions. (i.e. 12 = 12,000 BTU/Hr.
at 131/131 F)
3. 4 = 460 Volt
4. 6 = 50/60 Hz or 60 Hz only
5. Unique set of numbers for each air conditioner which identies the accessories on a model.

© 2020 nVent 89101404
- 4 -
TECHNICAL INFORMATION
SEQUENCE OF OPERATION
The air conditioner comes standard with two internally mounted thermostats. There are two modes of operation;
heating and cooling. During heating and cooling modes, the evaporator fan will be running.
HEATING
When the enclosure temperature is below the heating thermostat setpoint, power is applied to the
heaters. When the enclosure temperature is 10 degrees above the setpoint, the heater is powered off.
COOLING
When the enclosure temperature is above the cooling thermostat setpoint, power is applied through the
thermostat. The compressor is then energized either directly or through a contactor if unit requires one.
The condenser impellers will start immediately if the unit is not equipped with an optional head pressure
control switch. If the unit is equipped with an optional head pressure control switch, the condenser
impellers will start once the refrigerant pressure reaches the setting of the switch. Component specic
information is listed below.
Operating the air conditioner below the minimum ambient temperature or above the maximum ambient
temperatures indicated on the nameplate voids all warranties. DO NOT set the enclosure thermostat to a
temperature lower than 70 F. Doing so can increase the likelihood of frost buildup on the evaporator coil.
The moisture that the enclosure air can contain is limited. If moisture ows from the drain tube
continuously this can only mean that ambient air is entering the enclosure. Be aware that frequent
opening of the enclosure’s door admits humid air that the air conditioner must then dehumidify.
STANDARD AND OPTIONAL COMPONENT OPERATION
THERMOSTAT
The G52 air conditioner uses our standard 10-1061-16 thermostat. The thermostat setpoint equals the
temperature that the air conditioner turns off. The thermostat has a 10 F differential from setpoint until it
calls for cooling or heating. An example of operation is shown below.
FOR COOLING (75-100 F RANGE):
• Thermostat setpoint = 80 F
• Cooling turns on at 90 F
• Cooling turns off at 80 F
FOR HEATING (55-65 F RANGE):
• Thermostat setpoint = 55 F
• Heating turns on at 55 F
• Heating turns off at 65 F
NOTE: For testing purposes only, the thermostat stop screw may be removed (on units so
equipped) to allow settings below 70 F. After testing, replace the stop screw and verify that the
thermostat cannot be set below 70 F. Extended operation below 70 F can cause coil freeze ups
resulting in reduced load and/or unit damage.
REMOTE ACCESS CONTROL (OPTIONAL)
See REMOTE ACCESS CONTROL (optional) on page 12
HEAD PRESSURE CONTROL
Unit is set at the factory, no adjustment necessary.
At a saturated condenser temperature of 85 F (95 psig), the condenser fans will power off. At a saturated
condenser temperature of 118 F (165 psig), the condenser fans will power on.
CONTACTOR
The contactor on this model uses a 230V coil.
OVERLOAD
Set overload reset setting to automatic “A” and trip point dial to 3.0A.

© 2020 nVent
89101404 - 5 -
PHASE MONITOR
This product is equipped with Phase/Voltage Protection. Please verify correct phasing and voltage before
operating. Note the fans may still operate if phasing is incorrect, but the compressor will not, so the unit
will not cool. Illuminated light on Phase Monitor indicates phase is correct. See dimensional drawings on
page 10 and page 11 for phase monitor location
If the light is not illuminated, disconnect power from the unit and swap any two power leads at the
terminal block. This should correct the phasing. The light should now illuminate when power is reapplied.
460V TO 230V TRANSFORMER
The 230V from this transformer powers the fans, contactor and optional transformers. 460V is only used
to run the compressor.
230V TO 10V TRANSFORMER (OPTIONAL)
This transformer powers the thermal display only.
A230V TO 24V TRANSFORMER AND RELAY (OPTIONAL)
The transformer and relay are used to operate the condenser blower and compressor by using a customer
supplied, remote mounted door switch. This is not a safety door switch, but rather, only helps to reduce
condensation at the evaporator coil if the door is opened. The unit will remain electried when the door
switch is operated with the evaporator fan continuing to operate, and potentially, if temperatures are low
enough, the heater may continue to operate on outdoor models.

© 2020 nVent 89101404
- 6 -
SCHEMATICS AND WIRING DIAGRAMS FOR THERMOSTAT CONTROL
G52 GENERIC SCHEMATIC WITH THERMOSTATS (ACTUAL UNIT OPTIONS MAY VARY)

© 2020 nVent
89101404 - 7 -
G52 GENERIC WIRE DIAGRAM WITH THERMOSTATS (ACTUAL UNIT OPTIONS MAY VARY)
89171924
REV.A

© 2020 nVent 89101404
- 8 -
INSTALLATION INSTRUCTIONS WITH THERMOSTATS
1. Inspect the air conditioner and verify correct functionality before mounting the air conditioner. See
HANDLING AND TESTING THE AIR CONDITIONER on page 3.
2. Using the mounting gasket kit provided with the unit, install gaskets to the air conditioner, see
Figure 1 on page 9.
3. Mount air conditioner on enclosure taking care not to damage the mounting gasket. The
mounting gasket is the seal between the air conditioner and the enclosure. Avoid dragging the air
conditioner on the enclosure with the mounting gasket attached as this could cause rips or tears
in the gasket and risk losing the water tight seal.
4. To avoid cross-threading mounting inserts, start bolts by hand before tightening with a wrench or
ratchet driver.
5. Allow unit to remain upright for a minimum of ve (5) minutes before starting. CAUTION! Air
conditioner must be in upright position during operation.
6. Refer to the nameplate for electrical requirements. Wire the unit to a properly grounded power
supply. The unit’s terminal block is located behind the evaporator access panel on the rear
(enclosure side) of the unit. For 3 phase units, once power is applied, verify that phase monitor
light is illuminated which indicates correct electrical phasing. Electrical circuit should be fused
with slow blow or HACR circuit breaker.
7. Some air conditioners require a remote mounted thermostat. Wire the thermostat outputs to the
appropriate terminals on the 24 VAC terminal strip by noting the locations on the correct wiring
diagram.
8. Set thermostat for required cabinet temperature. Refer to dimensional drawings on page 10
and page 11 for thermostat location. Note that the thermostat dial is protected by a plastic
bushing during shipment. Remove and replace the plastic bushing to adjust the thermostat. Refer
to Sequence of Operation on page 4 for thermostat adjustment and operation.
INSTALLATION INSTRUCTIONS WITH REMOTE ACCESS CONTROL
1. Inspect the air conditioner and verify correct functionality before mounting the air conditioner. See
HANDLING AND TESTING THE AIR CONDITIONER on page 3.
2. Using the mounting gasket kit provided with the unit, install gaskets to the air conditioner, see
Figure 1 on page 9.
3. Mount air conditioner on enclosure taking care not to damage the mounting gasket. The
mounting gasket is the seal between the air conditioner and the enclosure. Avoid dragging the air
conditioner on the enclosure with the mounting gasket attached as this could cause rips or tears
in the gasket and risk losing the water tight seal.
4. To avoid cross-threading mounting inserts, start bolts by hand before tightening with a wrench or
ratchet driver.
5. Allow unit to remain upright for a minimum of ve (5) minutes before starting. CAUTION! Air
conditioner must be in upright position during operation.
6. Refer to the nameplate for electrical requirements. Wire the unit to a properly grounded power
supply. The unit’s terminal block is located behind the evaporator access panel on the rear
(enclosure side) of the unit. For 3 phase units, once power is applied, verify that phase monitor
light is illuminated which indicates correct electrical phasing. Electrical circuit should be fused
with slow blow or HACR circuit breaker.
7. Set controller setpoints for required cabinet temperature. Refer to Displaying and Changing
Program Variables on page 13 for setpoint adjustment and operation

© 2020 nVent
89101404 - 9 -
88015593
89061033
Surface Mount Surface Mount With Heat
88017668
Partial Recess Mount
Figure 1
Cutout Dimensions

© 2020 nVent 89101404
- 10 -
DIMENSIONAL DRAWINGS
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88016286

© 2020 nVent
89101404 - 11 -
8000 BTU/HR. WITH THERMOSTATS AND HEAT
PHASE MONITOR
WINDOW
52.63
1336.9
CLEANABLE, REUSABLE
ALUMINUM INLET FILTER
BEHIND REMOVABLE PANEL.
15.18
385.5
.97
24.7
17.12
434.9
11.65
296
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(2)
16.6
14.01
(2)
355.9
ENCLOSURE
AIR IN
AMBIENT
AIR IN
WARM
AIR OUT
REMOVABLE
HANGING
TABS
COOL
AIR OUT
.56 (6)
14.3
16.00
(6)
406.4
4.99
126.7
1.94
49.2
12.50
317.5
14.25
362
6.62
168.2 13.46
342
40.10
1018.4
7.50
190.5
9.88
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250.8
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41.3
1/4-20 UNC (12)
MOUNTING HOLES
COOLING
THERMOSTAT
POWER INLET
HEAT
THERMOSTAT
OPTIONAL ACCESS PANEL
(ONLY FOR UNITS WITH HEATER)
ACCESS HOLE TO
.375 [9.5] O.D. DRAIN STUB
NOTE:
APPROVE TO TYPE 3R/4/12. 1.
MOUNTING GASKET SUPPLIED (NOT SHOWN).
2.
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© 2020 nVent 89101404
- 12 -
REMOTE ACCESS CONTROL (OPTIONAL)
INTRODUCTION
The Remote Access Control is a parametric controller for the complete management of air conditioners. All
settings are pre-programmed at the factory. Cooling/heating set-points, cooling/heating differential and high /low
temperature alarm set-points can be adjusted by the user. Alarms are outputted through a relay contact and also
can be accessed through an Ethernet connection utilizing SNMP, EtherNet/IP and Modbus TCP. A USB connection
is also provided and can be used to interface with the controller utilizing Modbus RTU.
ENERGIZING THE CONTROLLER
The controller is wired and programmed at the factory to be energized when power is supplied to the air
conditioner.
CONTROL STATUS INDICATION
The display has numerous symbols that indicate if the controller is heating, cooling, alarming, if the compressor
is enabled, and if the ambient fan is enabled. The 3 alpha-numeric characters further describe alarms and show
the cabinet temperature by default.
SYMBOL COLOR ICON ON ICON FLASHING
1AMBER Compressor On Start-up Request
2,3,4 AMBER Not Used Not Used
AAMBER Compressor On Not Used
BAMBER Evaporator Fan On Start-up Request
CAMBER Not Used Not Used
DAMBER Not Used Not Used
EAMBER Heater Active Not Used
FRED Alarm Active Not Used
GAMBER Controller Active Not Used
HAMBER Not Used Not Used

© 2020 nVent
89101404 - 13 -
DISPLAYING AND CHANGING PROGRAM VARIABLES
Access: To view and/or change parameters, press and hold the Prg and Sel buttons for greater than 5 seconds.
Press the up or down arrow buttons until “22” is displayed, then press Sel button. When “S-P” is displayed, press
Sel.
Navigation: Press up or down arrows to display sub-menus then press Sel to select the desired sub-menu. In the
sub-menu, use up or down arrows to display parameters for viewing or changing and press Sel. Use Prg button to
back out of menu levels as desired.
Adjust: Use the up or down arrows to change the parameter value then push Sel to save that setting. If Sel is not
pressed, the change to the value will not be saved. Navigate to and change other parameters as desired. When
nished, push Prg to back out of the sub-menus to the main menu.
NOTE: The display will revert to normal temperature display mode if no buttons are pressed
for 60 seconds.
OPERATING PARAMETERS
Parameter Default Value Range Description
r01 80 F 72 F to 120 F Cooling set-point
r02 7 F -Cooling differential
A04 50 F* 32 F to 60 F Heating set-point*
A05 7 F* -Heating differential*
Cooling turns on at r01 + r02, and off at r01
Heating turns on at A04, and off at A04 + A05
*Functional only on units with heater option
ALARM PARAMETERS
Parameter Default Value Description
P16 125 F High Temperature Alarm
P19 40 F Low Temperature Alarm
DISPLAYING TEMPERATURE SENSOR #2
Sensor number 2, the air outlet or condenser coil sensor, can be viewed at any time by pressing the up or down
arrow button on the front panel of the controller display. The display will revert to displaying temperature sensor
number 1 (the AC inlet temperature) after 60 seconds. Both sensors can also be read through the Ethernet and
USB connections.
COMPRESSOR RESTART TIME DELAY
A factory set 6 minute (360 second) restart delay exists to reduce residual back pressure before allowing the
compressor to restart. The compressor will stay off for the entire restart duration after the compressor is
disabled. A ashing “1” on the controller display will indicate the unit is in a compressor restart delay while calling
for cooling.
ALARM OUTPUT CONTACT
The Remote Access Control has a normally open dry contact alarm output with a resistive load rating of 250
VAC at 3 amps. Two yellow 18 AWG wires located at the back of the air conditioner provide a connection to this
output.

© 2020 nVent 89101404
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ALARM INPUT CONNECTION
The Remote Access Control can accept a dry contact/switch input via the two 18 AWG white wires located at the
back of the air conditioner. This input is associated with the controller display alarm mnemonic TP (door open
and/or smoke detected). [To use this feature, remove the splice connector connecting the two white wires and
connect customer supplied enclosure door switch in its place.]
ALARM CONDITION DISPLAY
There are seven possible non-latching alarm conditions detectable by the controller and are indicated on the
controller display. All alarms can also be accessed through the Ethernet and USB connections.
Alarm Mnemonic Description Cause Result Alarm Relay
TP General Alarm Door open and/or
smoke detected Unit turns off for duration of alarm Relay Contacts Close
LA High Pressure Warning MALF high pressure
switch opens No effect on function N/A
E1 Air Inlet Temperature
Sensor Alarm Sensor Failure Unit turns off for duration of alarm Relay Contacts Close
E2 Air Outlet Temperature
Sensor Alarm Sensor Failure Unit turns off for duration of alarm Relay Contacts Close
Ht High Temperature Alarm
Default = 125 F
Cabinet over
temperature
Alarm clears at default
setting -2 F
No effect on function Relay Contacts Close
Lt Low Temperature Alarm
Default = 40 F
Cabinet under
temperature
Alarm clears at default
setting +27 F
No effect on function N/A
A1 Frost Alarm Evaporator coil frozen
Alarm clears at 59 F
Compressor and
Evaporator fan off for
duration of alarm Relay Contacts Close
AIR CONDITIONER UNIT COMMUNICATION FEATURES
Air conditioner units equipped with communication capabilities provide SNMP, EtherNet/IP and Modbus TCP
protocols through Ethernet and Modbus RTU protocol via USB. Hoffman®Cooling has a PC Interface Tool
available for download that can utilize either mode to communicate with the air conditioner unit.
USB COMMUNICATION
This communication mode allows direct connection of a PC to the air conditioner unit. The protocol
supported is Modbus RTU. Use the PC Interface Tool to communicate with the air conditioner unit. A
MINI-b USB connection is provided.
ETHERNET COMMUNICATION
This communication mode allows remote connection to the air conditioner unit using SNMP, EtherNet/IP
and Modbus TCP protocols. Customers using their own software can download a MIB le for SNMP, EDS
le or EtherNet_IP Object le for EtherNet/IP and Coil_Register le for Modbus TCP.
Note: ACU has a default IP Address of 192.168.1.2
Both Ethernet and USB communication modes allow the ability to:
• Read ACU inlet and outlet air temperatures
• Read and change Cooling Set-point and Cooling Differential
• Read and change Heating Set-point, Heating Differential
• Read and change High and Low Temperature Alarm Settings
• Read and change Gateway IP Address, Device IP Address, Subnet Mask, Trap IP Address and Community
• Read and change Unit Identication
• Read and change the state of IP addressing (static or dynamic)
• Read current Alarm Status
SOFTWARE AND CONFIGURATION FILE DOWNLOADS
The PC Interface Tool, MIB le, EDS le, EtherNet_IP Object le and Coil_Register le can be downloaded
from www.nVent.com/HOFFMAN.

© 2020 nVent
89101404 - 15 -
USING THE PC INTERFACE TOOL
The PC Interface Tool gives the user the ability to communicate with the air conditioner unit to read/write
parameters using either Ethernet or USB connections.
USB COMMUNICATION MODE
NOTE: Before connecting unit to the PC, make note of the comm ports present. After the unit
is connected to the PC, a new comm port will be added to the list. Use this new comm port.
• From Tools menu select Use Ethernet
• When Use Ethernet is unchecked, then Comm Port menu is enabled, Device IP and Community boxes are not
shown, and USB communication can be used
• To set the comm port, choose Comm Port from the Tools menu and then select the comm port from the combo box
VIEWING AIR CONDITIONER UNIT VALUES
To view Air Conditioner Unit values
• Select the ACU Values tab
• Select the Enable Comm button (the PC Interface will now be communicating with unit)
• To stop communication select the Disable Comm button
CHANGING AIR CONDITIONER UNIT VALUES
To change ACU Values
• Select the Settings tab
• Select the value to change
• Make the change to the value
• Select the Change Setting button
• Change can be veried in ACU Values tab
VIEWING AND CHANGING ETHERNET INFORMATION
To view and change Ethernet Information
• Select Ethernet Info tab
To view Ethernet Information
• Click Read Ethernet Info button
To change to dynamically assigning IP Address Mode
• Check Use DHCP Server checkbox
• Enter Trap IP Address and Community
• Click Load Ethernet Info button
To change to statically assigning IP Address Mode
• Uncheck Use DHCP Server checkbox
• Enter Device IP Address, Subnet Mask, Gateway IP Address, Trap IP Address and Community
• Click Load Ethernet Info button

© 2020 nVent 89101404
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ETHERNET COMMUNICATION MODE
• From Tools menu select Use Ethernet
• When Use Ethernet is checked, Comm Port selection is disabled, Device IP and Community boxes are shown and
Ethernet communication can be used.
• Enter unit’s IP Address and Community string in Device IP and Community boxes at the bottom of the PC Interface
Tool.
Each unit has two community strings. One is a Read/Write community string (defaulted to
‘private’) that can be changed by the customer (must be 4 to 8 characters long). The other is a
Read-Only community string (‘public’) and cannot be changed.
VIEWING AIR CONDITIONER UNIT VALUES
To view Air Conditioner Unit values
• Select the ACU Values tab
• Select the Enable Comm button (the PC Interface will now be communicating with unit)
• To stop communication select the Disable Comm button
CHANGING AIR CONDITIONER UNIT VALUES
To change ACU Values
• Select the Settings tab
• Select the value to change
• Make the change to the value
• Select the Change Setting button
• Change can be veried in ACU Values tab
VIEWING AND CHANGING ETHERNET INFORMATION
To view and change Ethernet Information
• Select Ethernet Info tab
To view Ethernet Information
• Click Read Ethernet Info button
To change to dynamically assigning IP Address Mode
• Check Use DHCP Server checkbox
• Enter Trap IP Address and Community
• Click Load Ethernet Info button
To change to statically assigning IP Address Mode
• Uncheck Use DHCP Server checkbox
• Enter Device IP Address, Subnet Mask, Gateway IP Address, Trap IP Address and Community
• Click Load Ethernet Info button
ALARM LOG ACCESSIBLE WITH SNMP
• Using custom software with the provided MIB le gives the ability to view a log of the last 25 alarms

© 2020 nVent
89101404 - 17 -
REMOTE ACCESS CONTROL PIN-OUT
FUNCTION NAME PIN # WIRE #
U1 OUTPUTS
COOL No1 1ORG78
C1/2 2BLK
HEAT No2 7BRN76
C1/2 3BLK
ENCL MI No3 8BLK77
C3/4 4BLK
NA No4 (na) 9BLK
C3/4 10 BLK
ALARM RELAY OUTPUT No5 12 YEL39
C5 6YEL38
NA x5NA
NA x11 NA
U2 INPUTS
ALARM INPUT
CONNECTION ID1 8WHT63
MALFUNCTION NC SWITCH ID2 1BLU88
NA ID3 (na) 9BLU
NA ID4 (na) 2BLU
NA ID5 (na) 10 BLU
DIGITAL INPUT GROUND ID GND 3BLU
NA Y (na) 4NA
NA GND (na) 5NA
T1, EVAP IN THERMISTOR B1 13 RED
T2, EVAP OUT THERMISTOR B2 12 RED
T1, T2 GND GND 6WHT
NA B3 11 NA
CONTROLLER POWER G 7 BLK40
CONTROLLER POWER G0 14 WHT41
U3 DATA
POWER 1RED
GROUND 2BLACK
DIRECTION 3GREEN
DATA 4WHITE

© 2020 nVent 89101404
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SCHEMATIC AND WIRING DIAGRAM FOR REMOTE ACCESS CONTROL
G52 GENERIC SCHEMATIC WITH REMOTE ACCESS CONTROL (ACTUAL UNIT OPTIONS
MAY VARY)
89096036 REV C

© 2020 nVent
89101404 - 19 -
G52 GENERIC WIRE DIAGRAM WITH REMOTE ACCESS CONTROL (ACTUAL UNIT OPTIONS
MAY VARY)
89082418 REV.J

© 2020 nVent 89101404
- 20 -
DIMENSIONAL DRAWINGS
G52 GENERIC MODEL DRAWING WITH REMOTE ACCESS CONTROL
89083019 Rev. D
ELECTRONIC
CONTROLLER
(INDOOR
APPLICATION)
ENCLOSURE
AIR IN
AIR IN
AIR OUT
TABS
COOL
AIR OUT
ACCESS HOLE TO
OPTIONAL ACCESS PANEL
ELECTRONIC
CONTROLLER
LOCATION
(OUTDOOR
APPLICATION)
ETHERNET
AND USB
CONNECTIONS
A
B