Trane Rtaaiom3 Manual
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91RTAA-IOM-3 Figure 50 RTAA Control Panel – 130 to 200 Tons with Remote Evaporator Option LEGEND: Device Designation Description 1F1-6 Fan Fuses, Circuit 1 1F7-12 Fan Fuses, Circuit 2 1F15 Control Circuit Fuse 1F16, 1F17 Primary Transformer Fuses 1K1, 1K5 Start Contactors 1K2, 1K6 Run Contactors 1K4, 1K8 Transition Contactors 1K5, 1K7 Shorting Contactors 1K9-12 Fan Contactors, Circuit 1 1K13-16 Fan Contactors, Circuit 2 1S1, 1S2 Non-fused Disconnect Switch 1T1 Control Power Transformer 1T2 Under/Over Voltage Transformer 1T3-5 Compressor Current Transformer, Circuit 1 1T6-8 Compressor Current Transformer, Circuit 2 1TB1, 1TB2 Line Voltage Terminal Blocks 1TB3 Terminal Strip, 115 V 1TB8, 1TB9 Terminal Strip, 24 V 1U1 Chiller Module 1U2 Options Module 1U3 Expansion Valve Module 1U4 Compressor Protection Module, Compressor A 1U5 Compressor Protection Module, Compressor B
93RTAA-IOM-3 Figure 52 Menu Formats OPERATING DISPLAY - MENU 0 Selected by setting the number 0 in the “P” menu item. Compressor/circuit indicators will be lit Continuously in this menu to indicate which compressors/ circuits are running. All items of Menu 0 are display only. Setpoint changes must be made in other menus. Display Code and Description P Menu Number A Operating Code b Last Diagnostic Code C Other Diagnostic Codes d Active Chilled Water Setpoint* E Evaporator Entering Water Temperature F Evaporator Leaving Water Temperature L Active Current Limit Setpoint *Dashes are displayed for the setpoint when the chiller is either in the “Ice Building” or “Ice Building Complete” mode. Menus There are six menus, four of which are shown on the operator interface panel and two factory displays, which are described later in this section. The menus are numbered as follows: Operating Display - Menu 0 Service #1 Display - Menu 1 Service #2 Display - Menu 2 Auxiliary Options Display - Menu 3 Factory Display - Menu 4 Factory Display - Menu 5 Each menu can be considered to be a page of data, formatted as shown in Figure 52. The operator can view one line of the menu at a time (menu item) on the digital display and can scroll through the menu by using the Display Up and Display Down keys. For example, when the digital display shows “P 0”, the UCM is in the “Operating Display” menu. By depressing the Display Down key one time, the next line of the menu, “Operating Code”, will be shown as an “A”, along with the current unit operating status. All operating and diagnostic codes are described on the “Condition Codes” label, as shown in Figure 53.There are a few exceptions to the scrolling function. When a menu selection represents multiple pieces of information: “C” Menu Item - Other Diagnostic Codes”: When this menu item is selected, depressing the Display Down key will display diagnostic history in code number sequence. Use the Display Up key to return to the top of the list. While in the “C” menu item, flashing indicates that the information is currently “true”, whereas steady, or non-flashing indicates historic data only. The digital display will not advance to the next item (d) until all diagnostics have been displayed. If there are no diagnostics to display, the data field will be blank for one key stroke. Compressor/Circuit Parameters: Because the unit has two, three or four compressors and two refrigerant circuits, items that refer to compressors or circuits will remain selected until information for all have been displayed. For example, assume a “29”, “Compressor Starts”, menu selection on a two compressor unit. The menu numbered “29” will be displayed and the indicator over the “A” compressor will be flashing. By depressing the Display Down key one time, the “29” will remain but the indicator light over the “B” compressor will be flashing. Another Display Downkey stroke will display menu “2A”, Compressor Hours, with compressor “A” indicator flashing. If either the Display Up or Display down keys are held down, the scrolling will continue until the key is released, or until reaching the top or bottom of the menu. In this case, the display will return to the “P” menu position and stop. To change menus, scroll to the “P” menu position and use the Set Point Up or Set Point Down keys. For example, assume that the display shows “P 0” and it is desired to view the Auxiliary Options on Menu 3. Depress the Set Point Up key three times and the “P 3” menu will be displayed. To return to Menu 0, depress the Set Point Down key three times or Set Point Up key once (to wrap around) and “P 0” will be displayed. This procedure will work for menus 0 through 3. A combination of key strokes is required to access menus 4 and 5. With the display in the “P” menu position (P), use the Set Point Up and Down keys to display “0, 1, 2, 1, 2, 3, 2, 3, 4”. Once in the “P 4” menu, use the Set Point Up key to access menu 5. All menus are always accessible, whether the unit is in a “running” or ‘stopped” mode.
94RTAA-IOM-3 Figure 52 Menu Formats (Continued) SERVICE #1 DISPLAY – MENU 1 Selected by setting the number 1 in the “P” menu item. The compressor circuit indicators will not be lit continuously in this menu to indicate which compressors are running. As the menu is advanced, the appropriate compressor/circuit indicator will flash. UCM Based Setpoint Display Code and Description Defaults Range P Menu Number 10 Front Panel Chilled Water Setpoint 44 F 0 to 65 F 11 Design Delta Temperature Setpoint 10 F 4 to 30 F 12 Differential to Start Setpoint 2 F 2 to 30 F 13 Front Panel Current Limit Setpoint 120% 40 to 120% 14 Outdoor Air Temperature (Optional) 15 Low Ambient Lockout - d/E (Optional) d 16 Low Ambient Lockout Setpoint - d/E (Optional)* 20 F -20 to 40 F 17 Cond. Entering Water Temperature (Optional) RTAA Non Applicable 18 Cond. Leaving Water Temperature (Optional) RTAA = Non Applicable 19 Service Pumpdown d/E (Stop/Reset only)** d 1A Circuit Lockout d/E** d 1b Circuit Diagnostics Reset** d *Dashes are displayed for the setpoint when the Low Ambient Lockout (15) is disabled. **Displayed by Compressor/Circuit SERVICE #2 DISPLAY - MENU 2 Selected by setting the number 2 in the “P” menu item. Compressor/Circuit indicators shall not be lit continuously in this menu to indicate which compressors are running. As the menu is advanced, the appropriate compressor/circuit indicator will flash. UCM Based Setpoint Display Code and Description Defaults Range P Menu Number 20 Compressor Mode* 21 Compressor Suction Refrigerant Temp.* 22 Compressor Evap. Refrigerant Temp.* 23 Evaporator Refrigerant Pressure* 24 Saturated Condenser Refrigerant Temp.* 25 Condenser Refrigerant Pressure* 26 EXV Test - d/E (Only in STOP/RESET)* d 27 Compressor % RLA (Highest leg)* 28 % Line Volts (Optional) 29 Compressor Starts (Optional)* 2A Compressor Hours (Optional)* 2b Compressor Test d/E d *Displayed by compressor/circuit Compressor Starts, Compressor Hours and % Line Volts will be displayed as dashes (e.g. “2A when this option is not installed. After the EXV test has been completed, the “E” will be automatically reset to “d”. See “Electronic Expansion Valve (EXV) Test”. The Condenser Refrigerant Pressure and the Evaporator Refrigerant Pressure, displayed on the UCM, are the saturated condenser and evaporator temperatures converted to R-22 pressure readings. The units are PSIG (Kilopascal gauge) and referenced to an elevation of sea level or 14.6960 psia (101.3289 KPa absolute).
95RTAA-IOM-3 Figure 52 Menu Formats (Continued) AUXILIARY OPTIONS – MENU 3 Selected by setting the number 3 in the “P” menu number position. Compressor/circuit indicators will not be lit continuously in this menu to indicate which compressors/circuits are running. UCM Based Setpoint Display Code and Description Defaults Range P Menu Number 30 External Chilled Water Setpoint - d/E d 31 External Current Limit Setpoint - d/E d 32 Ice Machine Control - d/E d 33 Active-Ice Termination Setpoint* 34 Front Panel Ice Termination Setpoint 27 F 20 to 31 F 35 Return Reset - d/E** d 36 Zone Reset - d/E** d 37 Outdoor Reset - d/E** d 38 Reset Ratio Setpoint*** Return50% 10 to 120% Zone100% 50 to 300% Outdoor 10% -80 to 80% 39 Start Reset Setpoint*** Return10 F 4 to 30 F Zone78 F 55 to 85 F Outdoor 90 F 50 to 130 F 3A Maximum Reset Setpoint*** Return5 F 0 to 20 F Zone5 F 0 to 20 F Outdoor5 F 0 to 20 F 3b External Circuit Lockout d/E d *Dashes are displayed for the setpoint when the chiller is not in the “Ice Building” or “Ice Building Complete” mode. **The UCM will permit only one type of reset (Return, Zone, or Outdoor) to be selected at one time. For example, if Return Reset is enabled, an attempt to enable Zone Reset would disable RETURN RESET and enable Zone Reset automatically. ***The UCM contains setpoints for each of the types of reset. The setpoint displayed will be for the type of reset enabled. If no reset is enabled, dashes will be displayed.
96RTAA-IOM-3 Figure 52 Menu Formats (Continued) FACTORY DISPLAY #1 - MENU 4 Caution: Do not leave unit unattended while in Menu 4 or 5. Inadvertent unit safety setpoint changes could occur. Selected by setting the number 4 in the “P” menu item. Unlike menus 0 through 3, the number 4 can only be set by entering a combination of numbers. This combination consists of a sequence of “P” menu numbers -0, 1, 2, 1, 2, 3, 2, 3. 4. Compressor/circuit indicators will not be lit continuously in this menu to indicate which compressors are running. As the menu is advanced the appropriate compressor/circuit indicator will flash. UCM Based Setpoint Display Code and Description Defaults Range P Menu Number 40 Leaving water Temp. Cutout Setpoint 35 F -10 to 35 F 41 Low Refrigerant Temp. Cutout Setpoint 22 F -39 to 35 F 42 Condenser Limit Setpoint - % HPC 90% 80 to 120% 43 Lead/Lag - d/E E 44 SI Display Units - d/E d 45 Unit Line Voltage* 460 V 46 Under/Over Voltage Protection - d/E d 47 Phase Imbalance Protection d/E E 48 Phase Reversal Protection d/E E 49 Superheat Setpoint 8 F 4 to 20 F 4A EXV Control Response Setpoint** 20 2 to 200 4b LWT Control Response Setpoint 40 2 to 220 4C ICS Address (Optional) 4d Fan Control Deadband Bias** 0 -50 to +50 4E Programmable Relay Setup 1 1 to 12 (see Alarm/Running/Maximum Capacity Contact Outputs) 4F Restart Inhibit Timer 120 sec. 30 to 120 sec. *Entry will be selected from 200, 220, 230, 346, 380, 415, 460, 500 or 575 volts. Dashes will be displayed if the Under/Over Voltage Protection option is not installed. **Displayed by circuit.
97RTAA-IOM-3 Figure 52 Menu Formats (Continued) FACTORY DISPLAY #2 - MENU 5 Caution: Do not leave unit unattended while in Menu 4 or 5. Inadvertent unit safety setpoint changes could occur. Selected by setting the number 5 in the “P” menu item. Unlike menus 0 through 3, the number 5 can only be set after menu 4 has been selected, as described on the previous page. Compressor/circuit indicators will not be lit continuously in this menu to indicate which compressors are running. As the menu is advanced the appropriate compressor/circuit indicator will flash. UCM Based Setpoint Display Code and Description Defaults Range P Menu Number 50 Number of Compressors 1 1, 2, 3, 4 51 Compressor Tons* 100 25, 30, 40,50, 60, 70, 85, 100 52 Low Water Temp EXV Gain Compensation d/e d 53 Fan Control - d/E E 54 Fans per Circuit** 7 4, 5. 6,7. 8, 10, 12, 14 55 Reduced Inrush Starting - d/E d 56 Compressor Current Overload Setting (to match DIP Switch)* 00 00 to 31 57 GP Compressor Unit d/E d 58 Low Ambient - Half Air Flow Fan d/E d 59 LATSM d/Ed 5A NNS d/Ed 5b Number of EXV Valves per Circuit** 1 1. 2 5c Future Option** d *Displayed by compressor. **Displayed by circuit
98RTAA-IOM-3 Figure 53 Condition/Diagnostic Codes UNIT OPERATING STATUS COMPRESSOR OPERATING STATUSCODE DESCRIPTION CODE DESCRIPTION Blank UCM Power Off 00Compressor Stop 888888.8 UCM Paw Up 16 Compressor Lockout 00 Unit Stop 17 Cprsr Service Pumpdown 01 Auto-Local 70 Cprsr Restart Inhibit 02 Auto-Remote 72 Cprsr Start 17 Service Pumpdown 74 Run Normal 70 Unit Restart Inhibit 75 Run: Current Limit 72 Unit Start 76 Run: Condenser Limit 74 Run:Normal 77 Run: Evaporator Limit 75 Run:Current Limit 7E Run:Unload 78 Run:Condenser Limit 77 Run:Evaporator Limit 7E Run:Unload 88 Reset DIAGNOSTIC TYPES100 External Unit Stop 101 Ice Building Complete MMR Machine Shutdown-Manual Reset 118 EXV Test CMR Circuit Shutdown-Man Reset 174 Ice Building; Normal MAR Machine Shutdown-Auto Reset 175 Ice Building: Current Limit CAR Circuit Shutdown-Auto Reset 176 Ice Building: Condenser Limit IFW Informational-Warning 177 Ice Building: Evaporator Limit 200 Low Ambient Run Inhibit UNIT DIAGNOSTICS CONDITIONFLASHING DISPLAY: MEANS: A xxx A New CMR, CAR. or IFW Diagnostic Exists. A xxx « C yyy Operating Code when MMR or MAR occurred. Diagnostic currently inhibiting operation. b yyy Manual reset required to restore full operation. This or other latching diagnostics exist. C yyy Condition creating MAR, CAR or IFW still exists. If MMR or CMR, manual reset required. 10 uu The chilled water setpoint is too close to a cutout setpoint. DASHES: MEANS: d ---- The chiller is in either ice bldg or ice bldg compl; Ivg chld wtr stpt is not applicable. 33 ---- The chiller is in normal cooling; the active ice termination setpoint is not applicable. Other (e.g. 14----) Option either not installed or not enabled. CODE DESCRIPTION TYPE CODE DESCRIPTION TYPE 87 Chock External Chilled Water Stpt IFW 19F Phase Loss - Cprsr D CMR 89 Check External Current Limit Stpt IFW 1AO Power Loss - Cprsr A CAR 8A Chilled Water Flow (Ent Wtr Temp) MMR 1A1 Power Loss - Cprsr 8 CAR 8E Evap Entering Water Temp Sensor MMR 1A2 Power Loss - Cprsr C CAR 8F Cond Rfgt Tamp Sensor - Ckt I CMR 1A3 Power Loss - Cprsr D CAR 90 Cond Rfgt Temp Sensor - Ckt 2 CMR 1A4 Remote communications Loss IFW 93 Evap Rfgt Temp Sensor - Ckt I CMR 1A5 Oil Flow Control - Cprsr A CMR 94 Evap Rfgt Tamp Sensor - Ckt 2 CMR 1A6 Oil Flow Control - Cprsr B CMR A0 Zone Temp Sensor IFW 1A7 Oil Flow Control - Cprsr C CMR A1 Outdoor Air Temp Sensor IFW 1A8 Oil Flow Control - Cprsr D CMR Ab Evap Leaving Wtr Temp Sensor MMR 1A9 EXV Elec Drive Ckt - Rfgt Ckt I CMR bA Overload Trip - Cprsr A CMR 1AA EXV Elec Drive Ckt - Rfgt Ckt 2 CMR bb Overload Trip - Cprsr 0 CMR 1Ad Memory Error Type I (See Oper Manual) IFW bC Overload Trip - Cprsr C CMR 1AE Low Differential Press - Ckt I CMR bd Overload Trip - Cprsr D CMR 1AF Low Differential Press - Ckt 2 CMR bE High Pressure Cutout - Cprsr C CMR 1b2 Severe Phase Unbalance - Cprsr A CMR bF High Pressure Cutout - Cprsr D CMR 1b3 Severe Phase Unbalance - Cprsr B CMR C5 Low Chilled Water Temp (Unit off) IFW 1b4 Severe Phase Unbalance - Cprsr C CMR C6 Low Chilled Water Temp (Unit on) MAR 1b5 Severs Phase Unbalance - Cprsr 0 CMR CA Contactor - Cprsr A MMR 1b6 Compressor Overload Setting - Cprsr A IFW Cb Contactor - Cprsr B MMR 1b7 Compressor Over load Setting - Cprsr B IFW cc Contactor - Cprsr C MMR 1b8 Compressor Overload Setting - Cprsr C IFW Cd Contactor - Cprsr D MMR 1b9 Compressor Overload Setting - Cprsr D IFW d7 Over Voltage MAR 1bA Phase Unbalance - Cprsr A CMR d8 Under Voltage MAR 1bb Phase Unbalance - Cprsr 8 CMR Ed Chilled Water Flow Interlock MAR 1bC Phase Unbalance - Cprsr C CMR F5 High Pressure Cutout - Cprsr A CMR 1bd Phase Unbalance - Cprsr D CMR F6 High Pressure Cutout - Cprsr B CMR 1bE Winding Temp. - Cprsr A CMR Fd Emergency Stop Input MMR 1bF Winding Temp. - Cprsr B CMR 180 Starter Transition - Cprsr A CMR 1C0 Winding Temp. - Cprsr C CMR 181 Starter Transition - Cprsr B CMR 1C1 Winding Temp. - Cprsr D CMR 182 Starter Transition - Cprsr C CMR 1C2 Discharge Temp. - Cprsr A CMR 183 Starter Transition - Cprsr D CMR 1C3 Discharge Temp. - Cprsr 8 CMR 184 Phase Reversal - Cprsr A CMR 1C4 Discharge Temp. - Cprsr C CMR 185 Phase Reversal - Cprsr 8 CMR 1C5 Discharge Temp. - Cprsr D CMR 186 Phase Reversal - Cprsr C CMR 1C6 High Differential Pressure - Ckt I CMR 187 Phase Reversal - Cprsr D CMR 1C7 High Differential Pressure - Ckt 2 CMR 190 Low Superheat - Ckt I CMR 1d1 Memory Error Type 11 (See Oper Manual) IFW 191 Low Superheat - Ckt 2 CMR 1d2 Memory Error Type III (See Oper Manual) IFW 194 Low Evap Rfgt Tamp - Ckt I CMR 1d3 Cprsr Suction Temp. Sensor - Ckt 1 CMR 195 Low Evap Rfgt Temp - Ckt 2 CMR 1d4 Cprsr Suction Temp. Sensor - Ckt 2 CMR 198 Low Oil I Flow - Cprsr A CMR 1d7 Phase Reversal Prot. Lost - Cprsr A CMR 199 Low 01 1 Flow - Cprsr B CMR 1d8 Phase Reversal Prot. Lost - Cprsr B CMR 19A Low Oil Flow - Cprsr C CMR 1d9 Phase Reversal Prot. Lost - Cprsr C CMR 19b Low Oil Flow - Cprsr D CMR 1dA Phase Reversal Prot. Lost - Cprsr D CMR 19C Phase Loss - Cprsr A CMR 1db Slave-Exv Elec Drive Ckt - Rfgt Ckt 1 CMR 19d Phase Lose - Cprsr B CMR 1dc Slave-Exv Elec Drive Ckt - Rfgt Ckt 2 CMR 19E Phase Loss - Cprsr C CMR 4xy See Operator’s Manual – – – X3956048201 Rev. B Condition Codes
99RTAA-IOM-3 Chiller Switch The chiller switch has three positions: Top Position AUTO REMOTE Middle Position AUTO LOCAL Bottom Position STOP/RESET With the switch in the AUTO REMOTE position, the chiller will operate normally using remote setpoints. Read and write remote communications may be performed. Any call for cooling based on Leaving Water Temperature (LWT) and the remote (e.g. Tracer) setpoints, will start the unit. The active chilled water setpoint (CWS) can be the remote CWS, a reset remote setpoint based on return, zone, or outdoor temperature reset, or a 4-20 mA/0-10 VDC external CWS. The active Current Limit Setpoint (CLS) can be the Remote CLS or a 4-20 mA/0-10 VDC External CLS. If remote communication is lost, the UCM will revert to the Front Panel (or local) chiller settings. When the chiller switch is in the AUTO LOCAL position, the chiller will operate normally using Front Panel (or local) setpoints. Read and write remote communications may be performed, but remote setpoints cannot be used for control. The unit will run when there is a call for cooling based on the LWT and the Front Panel or local setpoints. The active CWS can be the local setpoint, a reset setpoint based on return, zone, or outdoor temperature reset, or a 4-20 mA/0-10 VDC external CWS. The active Current Limit Setpoint can be the local setpoint or a 4-20 mA/ 0-10 VDC External CLS. Remote (e.g. Tracer) setpoints communicated over the serial communications link will be ignored, but remote devices can still read all unit control data.In the STOP/RESET position, the UCM is powered but operation of the unit is prevented. All outputs are de-energized and the chiller is stopped. The alarm relay output may be energized if an alarm condition exists. If any of the chillers are running when the chiller is put into the STOP/RESET position, the chiller will go into the Run: Unload mode for at least 20 seconds before shutting down the compressors. Although not a “position” on the chiller switch, it can be used to perform the function of manually resetting all latching diagnostics and clearing all historic diagnostics. Latching diagnostics can be reset by manually toggling the chiller switch from the STOP/RESET position to either AUTO position. Historic diagnostics (“C” menu item) can be cleared by depressing the “Display Down” key while manually toggling the chiller switch from the STOP/RESET position to either AUTO position (no compressor operating). Moving the chiller switch from the STOP/RESET position to either AUTO position will reset the controls, with one exception. If the chiller operating status is Run:Unload, this sequence will go to completion before the reset is executed. During the completion of the Run:Unload, the reset is “queued up” and operated on only after completion of the Run:Unload. After reset is completed, the digital display will return to “A” Operating Code.
100RTAA-IOM-3 Menu Function Descriptions and Selection Selecting Variables and Options All variables and options will be set by depressing the SET POINT UP and SET POINT DOWN keys. The setpoints will be increased or decreased by one least significant digit (1 F, 0. 1 C, or 1 integer value) with each key depression. If the key is held down, the setpoint will continue to be increased or decreased until the key is released. The minimum and maximum values of all setpoints are limited by system design and the setting operation will stop when either the minimum or maximum setpoint is displayed. See Figure 52 for setpoint ranges. Options are also selected using the SET POINT UP and SET POINT DOWN keys. Use the SET POINT UP key to select the “Enable” option and the letter “E” will appear on the display. Use the SET POINT DOWN key to select the “Disable” option and the letter “d” will be displayed. Certain items in Menus 4 and 5 will be integers with various endpoints and units. See Figure 52. Menu 0 – Operating Display A - Operating Code: This is the current unit operating status, e.g. A 74, which, as shown in Figure 53, is Run:Normal. b - Last Diagnostic Code: The last diagnostic detected by the UCM is stored and can be seen by displaying this I item. C - Other Diagnostics: All diagnostics detected by the UCM will be stored in preprescribed code number sequence, as shown in Figure 53, rather than the order in which they occurred. All flashing codes found under this item are currently active or “Latched” diagnostics. For additional information, see “Menus”. Diagnostics will be stored only once, even though the diagnostic may have occurred several times. There is no chronological sequence to the diagnostics that may be in the “C” menu item.d - Active Chilled Water Setpoint: The setpoint (display only) to which the chiller is controlling. This may be the same as the Front Panel Chilled water Setpoint (code 10 in Menu 1), but it may also be a setpoint that is being reset or loaded from a remote controller, such as a Tracer, multiple- machine controller, or a remote display panel. E - Evap. Entering Water Temp.: The temperature of the water as measured by the evaporator entering water temperature sensor. F - Evap. Leaving Water Temp.: The temperature of the water as measured by the evaporator leaving water temperature sensor. L - Active Current Limit Setpoint: The current limit setpoint (display only) to which the chiller is controlled. This may be the same as the Front Panel Current Limit setpoint (code 13 in Menu 1), but it may also be a setpoint that was loaded from a remote controller, such as a Tracer, multiple-machine controller. Menu 1 – Service #1 Display 10 - Front Panel Chilled Water Setpoint: The temperature selected at the UCM for the desired chilled water. 11 - Design Delta Temp. Setpoint: The difference between the entering and leaving chilled water temperatures at full load. This will be a function of GPM through the evaporator. 12 - Differential To Start Setpoint: This temperature, when added to the leaving chilled water setpoint, is the temperature at which the chiller will be started. Note: 1.5 F below chill water setpoint, the UCM will initiate an integrator to shut off the l ast compressor on a decrease in cooling load. 13 - Front Panel Current Limit Setpoint, The percent of current limit selected at the UCM for the system. See discussion in “Current Limit Setpoint”. 14 - Outdoor Air Temperature (Optional): The ambient temperature as measured by an outdoor temperature sensor.15 - Low Ambient Lockout (Optional): If the unit is installed with optional Outdoor Air Temperature Sensor, the entry in this code will enable or disable the setpoint in code 16. See discussion in “Low Ambient Lockout”. 16 - Low Amb. Lockout Setpoint (Optional): The temperature of the outside air below which the unit will not be permitted to operate. See discussion in “Low Ambient Lockout”. 17 - Cond. Entering Wtr. Temp.: Not applicable, with this air-cooled condenser unit. 18 - Cond. Leaving Wtr. Temp.: Not applicable, with this air- cooled condenser unit. 19 - Service Pumpdown: Must be manually “Enabled” by service personnel from the UCM display. The unit must be in STOP/RESET and service pumpdown can be performed only once for every power-up of the UCM. Restart inhibit will be ignored, the EXV will be prepositioned (20 seconds) and the compressor selected will start and run for one minute. Manual closing of the liquid line angle valve will be required. Caution: Do not pumpdown compressor more than once. 1A -Circuit Lockout: Allows service personnel to set a lockout, preventing a circuit from operating. With the display indicating the number of the circuit to be locked out, change the display to “E” for circuit lockout. Once circuit lockout is enabled, the circuit will remain locked out even through a reset or power down. Entering a “d” will return the circuit to operational status. 1b - Circuit Diagnostic Reset: Allows service personnel to reset a Circuit Manual Reset (CMR) diagnostic without having to terminate operation of the entire chiller via the STOP/RESET switch. With the display indicating the number of the circuit to be reset, change the display to “E” to reset. After reset, the display will automatically return to “d”.