Carrier 48LC 04 Controls, Start-up, Operation And Troubleshooting

Also see for 48LC 05: Controls, Start-Up, Operation and Troubleshooting Service and maintenance instructions Service and maintenance instructions

Carrier 48LC 04 Controls, Start-up, Operation And Troubleshooting Manual pdf 11 page image

11SERVICE TESTThe Service Test function can be used to verify proper operation ofcompressors, heating stages, indoor fan, power exhaust fans,economizer, and the alarm relay. Use of Service Test isrecommended at initial system start up and during troubleshooting(See Table 4 for point details).Service Test mode has the following changes from normaloperation:S Outdoor air temperature limits for cooling circuits, economizer,and heating are ignored. Normal compressor time guards andother staging delays are reduced to 30 seconds or less.S Circuit alerts are limited to 1 strike (versus 3) before changing toalarm shut down state.S The status of ALM.N is ignored so all alerts and alarms arebroadcast on CCN.S The words “SERVICE TEST” are inserted into every alarmmessage.Service test can only be turned ON/OFF at the unit display. Onceturned ON, other entries may be made with the display or throughCCN. To turn Service Test on, change the value of TEST to ON.To turn service test off, change the value of TEST to OFF.NOTE: Service Test mode may be password protected. Refer toBasic Control Usage section for more information. Depending onthe unit model, factory--installed options, and field--installedaccessories, some of the Service Test functions may not apply.Independent OutputsThe independent (INDP) submenu is used to change output statusfor the economizer, power exhaust stages, and alarm relay. Theseindependent outputs can operate simultaneously with other ServiceTest modes. All outputs return to normal operation when ServiceTest is turned off. When the economizer is using the factory defaultDigital Control Type (ConfigurationECONE.CTL is 1 or 2)then the Economizer Calibration feature may be used toautomatically check and reset the economizer actuator range ofmotion. Refer to the economizer operation section of more details.Fan TestThe fans (FANS) submenu is used to change output status for theindoor fan. On Direct Drive ECM fan units the indoor fan relayscan be energized or de--energized using the IDF1, IDF2, and IDF3test. For units with a VFD the indoor fan speed test (F.SPD) isavailable. F.SPD runs the fan at the desired speed entered. IDF FanMode (F.MOD) will run the fan at the programmed speed for eachmode.Cooling TestThe cooling (COOL) submenu is used to change output status forthe compressor, loader, and the low ambient outdoor fan. The fans(FANS) and heating (HEAT) service test outputs are reset to OFFfor the cooling service test. Indoor fans and outdoor fans arecontrolled normally to maintain proper unit operation. If LENVFD fan is configured, then the indoor fan speed will default to theSupply Cooling Fan Speed configuration point(ConfigurationI.FANF.SP2) when one compressor is turnedon. The Reduced Cool Fan Speed (F.SPD) can be used to changethe fan speed during cool test. When the compressor and loader areturned on the fan will run at Supply Fan Maximum Speed(FS.MX). On Direct Drive ECM units the fan will run Low Speedwhen the compressor is turned on and will run High Speed whenthe loader is turned on. The Reduced Cool Fan Speed (F.SPD) isnot used with ECM units. All normal cooling alarms and alerts arefunctional. The low ambient outdoor fan test (L.ODF) can beturned on and off while running the compressor.Table 4 – Service Test Modes and Submodes DirectoryDISPLAY MENU/ .SUB--- MENU/ . .NAMEEXPANDED NAME VALUESSERVICE TESTTEST Field Service Test Mode Off/OnINDP Test Independent OutputsECON Economizer Position Test 0 to 100%E.CAL Calibrate Economizer Off/OnPE.1 Power Exhaust 1 Test Off/OnPE.2 Power Exhaust 2 Test Off/OnALRM Alarm Relay Test Off/OnFANS Test FansF.SPD Indoor Fan Speed Test 0 to 100%F.MOD IDF Fan Mode 0 to 7IDF.1 Indoor Fan 1 Test Off/OnIDF.2 Indoor Fan 2 Test Off/OnIDF.3 Indoor Fan 3 Test Off/OnCOOL Test CoolingCMP.A Cool A Test Off/OnLDR_A Cir A Loader Test Off/OnF.SPD Reduced Cool Fan Speed 0 to 100%L.ODF Low Amb ODF Test 0 to 100%HEAT Test HeatingHT.1 Heat Stage 1 Test Off/OnHT.2 Heat Stage 2 Test Off/OnF.SPD Reduced Heat Fan Speed 0 to 100%Heating TestThe heating (HEAT) submenu is used to change output status forthe individual heat stages, gas or electric. The fans (FANS) andcooling (COOL) service test outputs are reset to OFF for theheating service test. Indoor and outdoor fans are controllednormally to maintain proper unit operation. The fan will run atSupply Fan Maximum speed (FS.MX) when running any heatoutput. The Reduced Heat Fan Speed (F.SPD) is not used at thistime. All normal heating alarms and alerts are functional.NOTE: Field terminal board terminal R must be connected to W1 forthe heat to operate in service test. Alert number T410 will occur as areminder if not done. If the normal unit control mode is thermostatmode, then remove the R--W1 jumper after completing service test.THIRD PARTY CONTROLThird party controls may interface with the unit ComfortLinkcontrols through the connections described below. See othersections of these instructions for more information on the relatedunit control and configurations.Cooling/Heating ControlThe thermostat inputs are provided on the field connection terminalboard. The Unit Control Type configuration,ConfigurationUNITU.CTL, must be 2 to recognize thebelow inputs. Terminal R is the 24vac source for the following:S Y1 = First stage coolingS Y2 = Second stage coolingS W1 = First stage heatingS W2 = Second stage heatingS G = Indoor fanDehumidification ControlThe HUM terminal can be used on the Field Connection boardwhen the isolation relay is installed between the MBB and TB.Humidity Switch configuration, ConfigurationUNITRH.SW,identifies the normally open or normally closed status of this inputat LOW humidity.NOTE: Dehumidification is considered a cooling function in thesoftware.48/50LC