nvent SPECTRACOOL NHZ36 Series User manual

© 2019 nVent 89117142
Rev. K P/N 89117142
SPECTRACOOL
Air Conditioner, HAzArdous LoCAtions
nHz36 ModeL
INSTRUCTION MANUAL
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WARRANTY AND RETURN POLICY
https://hoffman.nvent.com/en/hoffman/warranty-information
TABLE OF CONTENTS
WARRANTY AND RETURN POLICY....................................................................................................................................................................... 2
General Safety Information.................................................................................................................................................................................... 3
Receiving the Air Conditioner ................................................................................................................................................................................ 3
Handling and Testing the Air Conditioner ............................................................................................................................................................ 4
How to Read Model Numbers ............................................................................................................................................................................... 4
Technical Information ............................................................................................................................................................................................ 4
General ........................................................................................................................................................................................................................................ 4
Sequence of Operation.............................................................................................................................................................................................................. 4
Cooling ............................................................................................................................................................................................................................... 4
Standard and Optional Component Operation........................................................................................................................................................................ 5
SMART CONTROLLER....................................................................................................................................................................................................... 5
For cooling (75-100 F range)............................................................................................................................................................................................ 5
Remote Access Control (optional) .................................................................................................................................................................................. 5
Head Pressure Control (optional).................................................................................................................................................................................... 5
115V/230V to 10V Transformer (optional)..................................................................................................................................................................... 5
Door Switch ................................................................................................................................................................................................................................ 5
Active Condensate Management ............................................................................................................................................................................................. 5
When Used With Purge and Pressurized Enclosures.............................................................................................................................................................. 5
Schematics and Wiring Diagrams ............................................................................................................................................................................................ 6
Generic 1 PHASE Schematic (actual unit options may vary)........................................................................................................................................ 6
Generic 3 PHASE Schematic (actual unit options may vary)........................................................................................................................................ 6
Generic 1 Phase Wire Diagram (actual unit options may vary)..................................................................................................................................... 7
Generic 3 PHASE Wire Diagram (actual unit options may vary)................................................................................................................................... 8
Dimensional Drawing ............................................................................................................................................................................................. 9
General Safety Information.................................................................................................................................................................................. 10
Installation Instructions ....................................................................................................................................................................................... 10
Smart Controller ................................................................................................................................................................................................... 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
Remote Access Control ....................................................................................................................................................................................... 15
Air Conditioner Unit Communication Features...................................................................................................................................................................... 15
USB Communication....................................................................................................................................................................................................... 15
Ethernet Communication................................................................................................................................................................................................ 15
Using the PC Interface Tool..................................................................................................................................................................................................... 16
USB COMMUNICATION MODE ...................................................................................................................................................................................... 16
Ethernet Communication Mode..................................................................................................................................................................................... 17
Remote Access Control Pin-out.......................................................................................................................................................................... 18
General Safety Information.................................................................................................................................................................................. 18
Maintenance ......................................................................................................................................................................................................... 19
Compressor .............................................................................................................................................................................................................................. 19
Inlet Air Filter............................................................................................................................................................................................................................. 19
How To Remove, Clean or Install a New Inlet Air Filter......................................................................................................................................................... 19
Condensate Management and Drain Trap Maintenance...................................................................................................................................................... 19
Condenser and Evaporator Air Movers .................................................................................................................................................................................. 20
Refrigerant Loss....................................................................................................................................................................................................................... 20
Refrigerant Properties Chart (R134a)..................................................................................................................................................................................... 20
6000 BTU/Hr. Unit Characteristics ......................................................................................................................................................................................... 21
8000 BTU/Hr. Unit Characteristics ......................................................................................................................................................................................... 22
Functional Data ........................................................................................................................................................................................................................ 23
Service Data .......................................................................................................................................................................................................... 24
6000 BTU/Hr. Components List.............................................................................................................................................................................................. 24
8000 BTU/HR. Components List ............................................................................................................................................................................................ 25
NHZ360616GXXX Pressure Tables........................................................................................................................................................................................ 26
NHZ360626GXXX Pressure Tables........................................................................................................................................................................................ 27
NHZ360646GXXX Pressure Tables........................................................................................................................................................................................ 28
NHZ360816GXXX Pressure Tables........................................................................................................................................................................................ 29
NHZ360826GXXX Pressure Tables........................................................................................................................................................................................ 30
NHZ360846GXXX Pressure Tables........................................................................................................................................................................................ 31
F-Gas Information................................................................................................................................................................................................. 31
Trouble Shooting .................................................................................................................................................................................................. 32
Basic Air Conditioning Trouble Shooting Check List - SMART CONTROLLER.................................................................................................................... 32
Symptoms and Possible Causes - Remote Access Control Version................................................................................................................................... 33
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GENERAL SAFETY INFORMATION
Please observe the following general safety instructions when assembling and operating the unit:
• Assembling, installing and servicing must only be performed by properly trained specialists.
• When transporting the enclosure with the cooling unit externally mounted, always use an additional shipping brace
to support the cooling unit.
• Do not attempt to operate the air conditioner while it is horizontal or on its side, back or front.
• Operation of air conditioner in areas containing airborne caustics or chemicals can rapidly degrade sealing
properties of materials, deteriorate lters, refrigeration coils, blowers and motors. Contact nVent Equipment
Protection for special recommendations. See Maintenance on page 19.
DANGER
Danger: explosion hazard - do not energize, disconnect, or troubleshoot equipment
unless power has been switched off or the area is known to be non-hazardous.
Unit to be installed and maintained by properly trained personnel only.
Danger : Risque d’explosion – Ne pas alimenter, déconnecter ni dépanner
l’équipement si l’alimentation n’a pas été coupée ou si la zone n’est pas reconnue
comme non dangereuse.
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.
CAUTION
This air conditioner is suitable for use in Class 1, Division 2, Groups A, B, C, D T4A hazardous locations,
or non-hazardous locations only. It is meant to be installed in an enclosure such that the eld wiring and
controls are only accessible with the use of a tool.
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.
Ce climatiseur peut être utilisé dans des zones dangereuses de Classe 1, Division 2, Groupes A, B, C, D T4A
ou des zones non dangereuses uniquement. L’installation doit être effectuée dans une armoire de telle
sorte que le câblage et les commandes sur le terrain ne soient accessibles qu’à l’aide d’un outil.
Ne pas essayer de faire fonctionner le climatiseur en position horizontale, ou posé sur le côté, l’arrière ou
l’avant. Le compresseur de réfrigération est rempli d’huile lubriante. Cela endommagerait le climatiseur de
manière permanente et annulerait la garantie.
MISE EN GARDE
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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.
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
NHZ36 04 2 6 G300
12345
1. Identies the type/family of air conditioner and the approximate height (i.e. NHZ36 = Narrow
Hazardous Location family about 36 inches high).
2. This is the air conditioner’s listed capacity in BTU/Hr. at rated conditions. (i.e. 06=6,000 BTU/Hr. at
131/131 F)
3. 1 = 115 Volt, 2 = 230 Volt, 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.
TECHNICAL INFORMATION
GENERAL
Sensor 2 monitors the enclosure return air temperature to prevent ice buildup on the evaporator coil. If the air
temperature drops below -1 C, the compressor and condenser air mover(s) shut off. They turn back on when the
temperature rises above 15 C.
The compressor and the air movers are equipped with overload protection to guard against excess current and
temperatures.
SEQUENCE OF OPERATION
The air conditioner comes standard with smart controller. During cooling modes, the evaporator fan will be
running.
COOLING
When the enclosure temperature is above the cooling set-point plus the cooling differential, the smart
controller will call for cooling. The compressor is then energized through a solid state relay or contactor.
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 pressure 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 adjust cooling set-point 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.
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STANDARD AND OPTIONAL COMPONENT OPERATION
SMART CONTROLLER
The standard NHZ36 air conditioner uses our standard smart controller. The setpoint equals the
temperature that the air conditioner turns off. The controller has a 7 F differential from setpoint until it
calls for cooling. An example of operation is shown below.
FOR COOLING (75-100 F RANGE)
• Thermostat setpoint = 80 F
• Cooling turns on at 87 F
• Cooling turns off at 80 F
REMOTE ACCESS CONTROL (OPTIONAL)
See Remote Access Control on page 15
HEAD PRESSURE CONTROL (OPTIONAL)
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 117 F (165 psig), the condenser fans will power on.
115V/230V TO 10V TRANSFORMER (OPTIONAL)
This transformer powers the thermal display.
DOOR SWITCH
Several door switches may be connected in series and operated on one cooling unit. The door switch only
supports a oating connection,no external voltages. Remove jumper from terminals 3 and 4 of the connector and
connect the door switch to the two terminals if a door switch is available.
ACTIVE CONDENSATE MANAGEMENT
At low temperatures and high humidity levels inside the enclosure, condensation may form on the evaporator coil.
The air conditioner will continuously evaporate the water that may be in the drain pan due to condensation from
the evaporator coil into the external air stream. Excess condensate is routed downwards out of the air conditioner
via a tube tting at the bottom of the condenser side of the unit. A 10 mm inside diameter tube can be attached
to the tting and routed to a nearby drain.
WHEN USED WITH PURGE AND PRESSURIZED ENCLOSURES
This air conditioner will operate safely in a Class 1 Division 2 Groups A, B, C and D hazardous location on both
exterior and interior sides. It does not require a purge and pressurized enclosure, but if it is to be installed on one,
the following should be considered.
The active condensate management system functionally described above is possible due to a drain trap directly
connecting and routing condensation from the evaporator coil pan to the ambient side where it collects in the
condensate evaporator pan.
During initial purging of an enclosure or after long periods of operation in a pressurized system utilizing a dry
protective and/or inert gas supply, the drain trap can eventually dry out and allow a small amount of protective
gas to leak outward of the enclosure through the drain trap. A leakage should not immediately be associated with
a hazardous condition. If continuous positive pressure is maintained inside an enclosure, the protective gas will
leak out to ambient and prevent hazardous gasses from entering. A typical enclosure pressurization system can
compensate for this and maintain proper enclosure pressure.
If the pressurization system cannot compensate for the additional leakage, a drain trap seal can be created by
priming the air conditioner drain. This can be done by de-energizing and opening the enclosure for access to the
evaporator coil, and carefully pouring clean water (approx. 1 cup) into the face of the coil. With water present, the
drain trap should be fully primed and sealed. Opening the enclosure can also introduce humidity back into the
enclosure which will eventually condense on the evaporator coil and become part of the seal in the drain trap.
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SCHEMATICS AND WIRING DIAGRAMS
GENERIC 1 PHASE SCHEMATIC (ACTUAL UNIT OPTIONS MAY VARY)
GENERIC 3 PHASE SCHEMATIC (ACTUAL UNIT OPTIONS MAY VARY)
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GENERIC 1 PHASE WIRE DIAGRAM (ACTUAL UNIT OPTIONS MAY VARY)
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GENERIC 3 PHASE WIRE DIAGRAM (ACTUAL UNIT OPTIONS MAY VARY)
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DIMENSIONAL DRAWING
WARM
AIR OUT
AMBIENT
AIR IN
CLEANABLE, REUSABLE
ALUMINUM INLET AIR FILTER
PULLS OUT FRONT
ACCESS HOLE TO
.375 [9.5] O.D. DRAIN STUB
.78
19.7
14.00
355.7
9.37
238.1
11.50
292.1
36.01
914.7
22.31
566.7
ENCLOSURE
AIR IN
REMOVABLE
HANGING TABS
COOL
AIR OUT
DOOR SWITCH/
MALFUNCTION ALARM
MATING CONNECTOR
(SHIPPED LOOSE)
.50
12.7
28.80
731.5
16.50
419.1
2X
A
33.50
850.9
2X
8.00
203.2
5.00
127
10.00
254
25.00
635
2X
POWER
INPUT
SMART
CONTROLLER
DOOR SWITCH/
MALFUNCTION ALARM
CONNECTOR
REMOTE ACCESS
CONTROLLER
(OPTIONAL)
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GENERAL SAFETY INFORMATION
Please observe the following general safety instructions when assembling and operating the unit:
• Assembling, installing and servicing must only be performed by properly trained specialists.
• When transporting the enclosure with the cooling unit externally mounted, always use an additional shipping brace
to support the cooling unit.
• Do not attempt to operate the air conditioner while it is horizontal or on its side, back or front.
• Operation of air conditioner in areas containing airborne caustics or chemicals can rapidly degrade sealing
properties of materials, deteriorate lters, refrigeration coils, blowers and motors. Contact nVent Equipment
Protection for special recommendations. See Maintenance on page 19.
DANGER
Danger: explosion hazard - do not energize, disconnect, or troubleshoot equipment
unless power has been switched off or the area is known to be non-hazardous.
Unit to be installed and maintained by properly trained personnel only.
Danger: Risque d’explosion – Ne pas alimenter, déconnecter ni dépanner
l’équipement si l’alimentation n’a pas été coupée ou si la zone n’est pas reconnue
comme non dangereuse.
INSTALLATION INSTRUCTIONS
1. Refer to nameplate for hazardous location rating.
2. Install a suitable switch to de-energize the air conditioner for repairs or remove the fuse.
3. Inspect the air conditioner and verify correct functionality before mounting the air conditioner. See
Handling and Testing the Air Conditioner on page 4.
4. Using the mounting gasket kit provided with the unit, install gaskets to the air conditioner.
5. When considering a location for the unit, it is recommended that a six (6) inch clearance be
maintained on at least one side of the air conditioner. It is also recommended that twenty (20)
inches of clearance be allowed from the front of the unit for cover removal.
6. Figure 1 and the cutout template included with the unit will assist in preparing the enclosure for
installation of the unit. NOTE: Mount the unit within 3° from vertical.
7. 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.
8. To avoid cross-threading mounting inserts, start bolts by hand before tightening with a wrench or
ratchet driver.
9. Allow unit to remain upright for a minimum of ve (5) minutes before starting. CAUTION! Air
conditioner must be in upright position during operation.
10. Refer to the nameplate for electrical requirements. Wire the unit to a properly grounded power
supply. Electrical circuit should be fused with slow blow or HACR circuit breaker.
11. Adjust the controller to the desired cabinet temperature. Refer to Displaying and Changing
Program Variables on page 13 for controller adjustments and operation.
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CAUTION
The unit is meant to be installed in an enclosure suitable for the environment listed previously and such that
the eld wiring and controls are only accessible with the use of a tool.
When installed on an enclosure, only the front/face side, ambient air in, and ambient air out can be exposed
to the environment.
L’unité doit être installée dans une armoire adaptée à l’environnement susmentionné et de telle sorte que le
câblage et les commandes sur le terrain ne soient accessibles qu’à l’aide d’un outil.
Lors d’une installation sur une armoire, seule la face avant/latérale, l’entrée d’air ambiant et la sortie d’air
ambiant peuvent être exposées à l’environnement.
MISE EN GARDE
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 

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 

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89074387
Surface Mount
Figure 1
Cut-out Drawing
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SMART CONTROLLER
INTRODUCTION
The smart controller is a parametric controller for the complete management of air conditioners. All settings are
pre-programmed at the factory. Cooling set-points, cooling differential and high/low temperature alarm set-points
can be adjusted by the user. Alarms are outputted through a relay contact.
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 cooling or 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 Not Used
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
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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 one (1) on the controller display will indicate the unit is in a compressor restart delay while
calling for cooling. If the time delay is reduced to less than ve (5) minutes, this may cause reduced compressor
life.
ALARM OUTPUT CONTACT
The smart controller has a normally open, dry contact, alarm output with a resistive load rating of 24 VAC at
261 mA. A connector located on the enclosure side of the unit provides a 2-pin connection to this output marked
YEL/ALARM.
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ALARM INPUT CONNECTION
The smart controller can accept a dry contact/switch input via the connector terminals marked WHT/DS1 and
WHT/DS2 located on the enclosure side of the unit. This input is associated with the controller display alarm
mnemonic TP (door open and/or smoke detected). To use this feature, remove the jumper wire connecting
terminals DS1 and DS2 and replace with customer supplied wires from the enclosure door switch to DS1 and DS2
terminals.
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 with the optional
communications board.
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 Relay Contacts Close
A1 Frost Alarm Evaporator coil frozen
Alarm clears at 59 F Compressor fan off for duration of alarm Relay Contacts Close
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REMOTE ACCESS CONTROL
AIR CONDITIONER UNIT COMMUNICATION FEATURES
Air conditioner units equipped with communication capabilities provide SNMP, EtherNet/IP, Modbus TCP and
Pronet 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, Modbus TCP and Pronet 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 and
GSDML le for Pronet.
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, Coil_Register le and GSDML le for
Pronet can be downloaded from:
www.nvent.com/HOFFMAN/en/na/Product-Enclosure-Cooling-Heating
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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
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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
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REMOTE ACCESS CONTROL PIN-OUT
FUNCTION NAME PIN #
U1 OUTPUTS
COOL No1 1
C1/2 2
C1/2 3
ALARM RELAY OUTPUT No5 12
C5 6
U2 INPUTS
ENCLOSURE DOOR SWITCH ID1 8
MALFUNCTION NC SWITCH ID2 1
NA ID3 (na) 9
NA ID4 (na) 2
DIGITAL INPUT GROUND ID GND 3
T1, EVAP IN THERMISTOR B1 13
T2, EVAP OUT THERMISTOR B2 12
T1, T2 GND GND 6
NA B3 11
CONTROLLER POWER G 7
CONTROLLER POWER G0 14
U3 DATA
POWER 1
GROUND 2
DIRECTION 3
DATA 4
GENERAL SAFETY INFORMATION
Please observe the following general safety instructions when assembling and operating the unit:
• Assembling, installing and servicing must only be performed by properly trained specialists.
• When transporting the enclosure with the cooling unit externally mounted, always use an additional shipping brace
to support the cooling unit.
• Do not attempt to operate the air conditioner while it is horizontal or on its side, back or front.
• Factory-supplied replacement parts must be used.
• Repaired/replaced components must be located and wired in the identical location as the original components.
• Hazardous Location rating may be compromised if the above are not followed.
• Operation of air conditioner in areas containing airborne caustics or chemicals can rapidly degrade sealing
properties of materials, deteriorate lters, refrigeration coils, blowers and motors. Contact nVent Equipment
Protection for special recommendations.
DANGER
Danger: explosion hazard - do not energize, disconnect, or troubleshoot equipment
unless power has been switched off or the area is known to be non-hazardous.
Unit to be installed and maintained by properly trained personnel only.
Danger: Risque d’explosion – Ne pas alimenter, déconnecter ni dépanner
l’équipement si l’alimentation n’a pas été coupée ou si la zone n’est pas reconnue
comme non dangereuse.
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MAINTENANCE
COMPRESSOR
The compressor requires no maintenance. It is hermetically sealed, properly lubricated at the factory and should
provide years of satisfactory operating service.
Under no circumstances should the access tting covers be loosened, removed or tampered with.
Breaking of seals on compressor access ttings during warranty period will void warranty on hermetic system.
Recharging ports are provided for the ease and convenience of reputable refrigeration repair service personnel for
recharging the air conditioner.
INLET AIR FILTER
This air conditioner was designed with a dust resistant condenser coil. This allows it to be run lterless in most
applications. The air conditioner is shipped with a lter in place for your convenience. For lterless operation,
simply remove the lter. Should you decide the lter is necessary in your application, regular maintenance to
clean this lter will assure normal operation of the air conditioner. The easily removable inlet air lter is located
behind the inlet of the front cover. If necessary lter maintenance is delayed or ignored, the maximum ambient
temperatures under which the unit is designed to operate will be decreased.
If the compressor’s operating temperature increases above designed conditions due to a dirty or clogged
lter (or plugged condenser coil), the air conditioner’s compressor will stop operating due to actuation of the
thermal overload cut-out switch located on the compressor housing. As soon as the compressor temperature
has dropped to within the switch’s cut-in setting, the compressor will restart automatically. However the above
condition will continue to take place until the lter or coil has been cleaned. It is recommended that power to
the air conditioner be interrupted intentionally when abnormally high compressor operating temperature causes
automatic shut-down of the unit. The above described shut-down is symptomatic of a clogged or dirty lter, thus
causing a reduction in cooling air ow across the surface of the compressor and condenser coil.
HOW TO REMOVE, CLEAN OR INSTALL A NEW INLET AIR FILTER
RP aluminum washable air lters are designed to provide excellent ltering eciency with a high dust holding
capacity and a minimum amount of resistance to air ow. Because they are constructed entirely of aluminum
they are lightweight and easy to service. To achieve maximum performance from your air handling equipment, air
lters should be cleaned on a regular basis.
The inlet air lter is located behind the condenser air inlet grille. To access the lter, simply slide it out. The lter
may now be cleaned or a new lter installed.
Cleaning Instructions:
1. Flush the lter with warm water from the exhaust side to the intake side. DO NOT USE CAUSTICS.
2. After ushing, allow lter to drain. Placing it with a corner down will assure complete drainage.
CONDENSATE MANAGEMENT AND DRAIN TRAP MAINTENANCE
The drain trap can be cleaned by pouring soapy water into the face of the evaporator coil. An alternate method is
to remove the panel underneath the condenser coil, locate the drain trap above the condensate evaporator pan,
and blow compressed air through the tube.
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CONDENSER AND EVAPORATOR AIR MOVERS
Impeller motors require no maintenance. All bearings, shafts, etc. are lubricated during manufacturing for the life
of the motor.
If the condenser impeller motors (ambient impellers) should fail, it is not necessary to remove the air conditioner
from the cabinet or enclosure to replace the blower. The condenser impeller is mounted on its own bracket and is
easily accessible by removing the front cover.
If the evaporator impeller motor should fail, it may require dismounting the unit from the enclosure because
access to the evaporator is through the enclosure side. After it is repaired, refer to Installation Instructions on
page 10 for mounting the unit back onto the enclosure. Replace the mounting gasket if damaged.
Operation of air conditioner in areas containing airborne caustics or chemicals can rapidly degrade sealing
properties of materials, deteriorate lters, refrigeration coils, blowers and motors.
Contact nVent Equipment Protection for special recommendations.
Le fonctionnement du climatiseur dans des espaces contenant des produits caustiques ou chimiques en
suspension dans l’air peut rapidement dégrader les propriétés d’étanchéité des matériaux, détériorer les ltres,
les serpentins du condenseur, les ventilateurs et les moteurs.
Communiquer avec nVent Equipment Protection pour connaître les recommandations spéciales.
CAUTION MISE EN GARDE
REFRIGERANT LOSS
Each air conditioner is thoroughly tested prior to leaving the factory to insure against refrigeration leaks. Shipping
damage or microscopic leaks not found with sensitive electronic refrigerant leak detection equipment during
manufacture may require repair or recharging of the system. This work should only be performed by qualied
professionals, generally available through a local, reputable air conditioning repair or service company.
Should the refrigerant charge be lost, access ports on the suction and discharge sides of the compressor are
provided for recharging and/or checking suction and discharge pressures.
Refer to the data on the nameplate which species the type of refrigerant and the charge size in ounces.
Before recharging, make sure there are no leaks and that the system has been properly evacuated into a deep
vacuum.
REFRIGERANT PROPERTIES CHART (R134A)
°F °C Pressure °F °C Pressure
-40 -40 -14.7 60 15.6 58
-35 -37.2 -12.3 65 18.3 64
-30 -34.4 -9.7 70 21.1 71.5
-25 -31.7 -6.8 75 23.9 78
-20 -28.9 -4 80 26.7 86.7
-15 -26.1 085 29.4 95
-10 -23.3 290 32.2 105
-5 -20.6 495 35 113.3
0-17.8 7.5 100 37.8 125
5-15 9105 40.6 135
10 -12.2 12 110 43.3 146.7
15 -9.4 15 115 46.1 157.5
20 -6.7 18.5 120 48.9 170
25 -3.9 22 125 51.7 185
30 -1.1 26
35 1.7 30
40 4.4 35
45 7.2 40
50 10 45.5
55 12.8 51.5
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