Carrier INFINITY 24ANA Installation Instructions Manual

Also see for 24ANA1 Infinity: Product data Wiring diagram

Contents

Carrier INFINITY 24ANA Installation Instructions Manual Manual pdf 7 page image

7System Functions And Sequence Of OperationThe outdoor unit control system has special functions. Thefollowing is an overview of the 2--stage control functions:Cooling Operation24ANA7 and 24ANA1 (containing circuit board HK38EA015 ornewer) models utilize either a 2--stage cooling indoor thermostat oran Infinity communicating User Interface. With a call for firststage cooling, the outdoor fan and low--stage compressor areenergized. If low--stage cannot satisfy cooling demand, high--stageis energized by the second stage of indoor thermostat or UserInterface. After second stage is satisfied, the unit returns tolow--stage operation until first stage is satisfied or until secondstage is required again. When both first stage and second stagecooling are satisfied, the compressor will shut off.NOTE: On 24ANA7 models, if unit has not operated within thepast 12 hrs, or following a unit power--up, upon the nextthermostat high-- or low--stage demand, unit operates for aminimum of 5 minutes in high--stage.NOTE: With non--communicating (non--Infinity) systems, withfirst stage of cooling, (Y1) is powered on; and with second stage ofcooling, (Y1 and Y2) are on.NOTE: When 2--stage unit is operating at low--stage, systemvapor (suction) pressure will be higher than a standardsingle--stage system or high--stage operation.NOTE: Outdoor fan motor will continue to operate for oneminute after compressor shuts off, when outdoor ambient is greaterthan or equal to 100_F (37.78_C). This reduces pressuredifferential for easier starting on the next cycle.Communication and Status Function LightsFor Infinity Control Only, Green communications (COMM)LightA green LED (COMM light) on the outdoor board (see Fig. 6)indicates successful communication with the other systemproducts. The green LED will remain OFF until communications isestablished. Once a valid command is received, the green LED willturn ON continuously. If no communication is received within 2minutes, the LED will be turned OFF until the next validcommunication.Amber Status LightAn amber colored STATUS light is used to display the operationmode and fault codes as specified in the troubleshooting section.See Table 6 for codes and definitions.NOTE: Only one code will be displayed on the outdoor unitcontrol board (the most recent, with the highest priority).Utility InterfaceWith Infinity ControlThe utility curtailment relay should be wired between R and Y2connections on the control board for Infinity CommunicatingSystems only (see Fig. 6.) This input allows a power utility deviceto interrupt compressor operation during peak load periods. Whenthe utility sends a signal to shut the system down, the UserInterface will display, “Curtailment Active”.One Minute Stage Change Time Delay on 24ANA7ModelsWhen compressor changes stages from high to low or low to high,there is a 1--minute time delay before compressor restarts. Theoutdoor fan motor remains running.Compressor Operation on 24ANA7 ModelsWhen the compressor operates in high--stage operation, the motorrotates clockwise. Both the lower and upper pistons are eccentricwith the rotating crankshaft and both compress refrigerant.When the compressor operates in low--stage operation the motorreverses direction (rotates counterclockwise). The lower pistonbecomes idle and the upper piston compresses refrigerant. Thestart and run windings are reversed.UTILITY RELAY *UTILITY SIGNALOPEN RELAY* SUPPLIED BY UTILITY PROVIDERLLSLiquid Line SolenoidMODELPLUGA06526Fig. 6 -- 2--Stage Control Board24ANA