Carrier 48HC 04-28 Controls, Start-up, Operation And Troubleshooting

Also see for /50HC 04-28: Manual

Contents

Carrier 48HC 04-28 Controls, Start-up, Operation And Troubleshooting Manual pdf 16 page image

16Heating TestThe heating (HEAT) submenu is used to change output statusfor the individual heat stages, gas or electric. The fans (FANS)and cooling (COOL) service test outputs are reset to OFF forthe heating service test. Indoor and outdoor fans are controllednormally to maintain proper unit operation. All normal heatingalarms and alerts are functional.NOTE: Field terminal board terminal R must be connected to W1for the heat to operate in service test. Alert number T410 will oc-cur as a reminder if not done. If the normal unit control mode isthermostat mode, then remove the R-W1 jumper after completingservice 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 relat-ed unit control and configurations.Cooling/Heating ControlThe thermostat inputs are provided on the field connection ter-minal board. The Unit Control Type configuration, Configura-tionUNITU.CTL, must be 2 to recognize the below in-puts. Terminal R is the 24vac source for the following:• Y1 = First stage cooling• Y2 = Second stage cooling• W1 = First stage heating• W2 = Second stage heating• G = Indoor fanDehumidification ControlOn HumidiMiZer units the HUM terminal is provided on thefield connection terminal board. Humidity Switch configura-tion, ConfigurationUNITRH.SW, identifies the normallyopen or normally closed status of this input at HIGH humidity.NOTE: Dehumidification is considered a cooling function in thesoftware.Remote OccupancyThe remote occupancy input is provided on the field connectionterminal board (TB). The Remote Occupancy Switch configura-tion, ConfigurationUNITRM.SW, identifies the normallyopen or normally closed status of this input when unoccupied.• RMOL = 24 VAC signal input• R-2 = 24 VAC source for dry contactFire ShutdownThe fire shutdown input is provided for unit shutdown in re-sponse to a fire alarm or smoke detector. The Fire ShutdownSwitch configuration, ConfigurationUNITFS.SW, identi-fies the normally open or normally closed status of this inputwhen there is no fire alarm.• FDWN = 24 VAC signal inputAlarm OutputThe alarm output is provided on the field connection terminalboard to indicate a current alarm status. The output will be24VAC if a current alarm exists.• C-2 = 24 VAC common• X = 24 VAC signal outputEconomizer Damper ControlFor units with the economizer option or accessory and the ECBcontrol board, the damper position can be directly controlledthrough the IAQ sensor input provided on the field connectionterminal board. The IAQ Analog Input configuration,ConfigurationAIR.QIA.CF will have to set to 3 (ControlMinimum Position). When IA.CF = 3, an external 4 to 20 mAsource is used to move the damper 0% to 100% directly.IAQ = 4-20mA + signalCOM = 4-20mA - commonNOTE: In this mode, preset minimum positions configurationsare not valid, the damper position may exceed the input posi-tion to provide economizer cooling and CO 2 sensor input cannot be used for DCV control. Refer to the Indoor Air Qualityoperation section on page 27 for more information.CONTROLS OPERATIONDisplay ConfigurationThe ConfigurationDISP submenu is used to configure thelocal display settings.Metric Display (METR)This variable is used to change the display from English unitsto Metric units.Language Selection (LANG)This variable is used to change the language of the Com-fortLink display. At this time, only English is available.Password Enable (PROT)This variable enables or disables the use of a password. Thepassword is used to restrict use of the control to change config-urations.Service Password (PSWD)This variable is the 4-digit numeric password that is required ifenabled.Test Display LEDs (TEST)This is used to test the operation of the ComfortLink display.Unit ConfigurationMany configurations that indicate what factory options and/orfield accessories are installed and other common operationvariables are included in Unit Configuration (Configura-tionUNIT). These configurations will be set in the factoryfor the factory-installed options (FIOPs). Field-installed acces-sories installed will require configuration changes. Generalunit and fan control configurations are also covered under thisUnit Configuration menu.Start-Up Delay (S.DLY)This configuration sets the control start-up delay after the pow-er is interrupted. This can be used to stagger the start-up ofmultiple units.Unit Control Type (U.CTL)This configuration defines if temperature control is based onthermostat inputs or space temperature sensor input.• U.CTL = 2 (Thermostat) — The unit determines coolingand heating demand by the state of G, Y1, Y2,W1, and W2inputs from a space thermostat. This value is the factorydefault.• U.CTL = 3 (Space Sensor) — The unit determines coolingand heating demand based on the space temperature andthe appropriate set point. Used also as Linkage configura-tion. The jumper wire in the installer’s packet must be con-nected between R and W1 on the low voltage terminalboard for heating mode to operate.THERMOSTAT CONTROL TYPE (T.CTL)This configuration applies only if Unit Control Type is Thermo-stat (ConfigurationUnitU.CTL = 2). The value determinesalternative cooling and Humidi-MiZer circuit staging. See theCooling and Humidi-MiZer sections for more information. Thefactory default value is T.CTL = 0 (Adaptive).