Carrier 48HC 04-28 Manual

Also see for /50HC 04-28: Controls, Start-Up, Operation and Troubleshooting

Carrier 48HC 04-28 Manual Manual pdf 13 page image

13Heating 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. 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 occuras 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 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 ControlOn Humidi--MiZert, units the HUM terminal is provided on thefield connection terminal board. Humidity Switch configuration,Configuration→UNIT→RH.SW, identifies the normally open ornormally closed status of this input at LOW 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 Switchconfiguration, Configuration→UNIT→RM.SW, identifies thenormally open or normally closed status of this input whenunoccupied.S RMOL = 24 VAC signal inputS R--2 = 24 VAC source for dry contactFire ShutdownThe fire shutdown input is provided for unit shutdown in responseto a fire alarm or smoke detector. The Fire Shutdown Switchconfiguration, Configuration→UNIT→FS.SW, identifies thenormally open or normally closed status of this input when there isno fire alarm.S FDWN = 24 VAC signal inputAlarm OutputThe alarm output is provided on the field connection terminalboard to indicate a current alarm status. The output will be 24VACif a current alarm exists.S C--2 = 24 VAC commonS 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 configurations arenot valid, the damper position may exceed the input position toprovide economizer cooling and CO 2 sensor input can not be usedfor DCV control. Refer to the Indoor Air Quality operation sectionfor more information.ComfortLINK v1.X