Carrier 48GP (N) 024-060 Installation And Operating Instructions Manual

Contents

This configuration provides the following comfort enhance-ments:(a.) A 30 sec blower on delay with 150 sec at 70 percentairflow to allow the indoor coil to warm up or cooldown before the blower is asked to deliver 100 percentairflow reducing the cold blow sensation at start up inheating and allowing the indoor coil to more quicklyreach wet coil operating conditions in cooling.(b.) A no blower off delay eliminates cold blow which maybe associated with running the blower after shut downof the compressor and avoids re-evaporation of con-densed moisture after cooling/dehumidifying opera-tion.(c.) Lower airflow while the compressor is running toreduce draft effects and increase heating air tempera-ture and improved humidity control during coolingoperation.ACCESSORY INSTALLATIONa. ACCESSORY ELECTRIC HEATERSElectric heaters may be installed with the 50GL & 50JZ unitsper instructions supplied with electric heater package. See unitrating plate for factory-approved electric heater kits.b. AUXILIARY TERMINALSThe AUX and HUM terminals on the Easy Select™ Board aretied directly to the G terminal, and provide a 24-v. signalwhenever the G terminal is energized (See Fig. 12). DuringSuper dehumidify mode, the G signal is not present and theauxiliary terminals are not energized. If the installation includesthe use of the operating mode, do not use these terminals tocontrol accessories. See Electronic Air Cleaner and Humidifiersections for further information.c. ELECTRONIC AIR CLEANER CONNECTIONSThe AUX1 and AUX2 terminals are not always energizedduring blower operations, as described above. When using anelectronic air cleaner with the unit, use Airflow Sensor P/NKEAAC0101AAA. The airflow sensor turns on electronic aircleaner when the blower is operating.d. HUMIDIFIER/HUMIDISTAT CONNECTIONSEasy Select™ Board terminals HUM1 and HUM2 are providedfor direct connection to the low-voltage control of a humidifierthrough a standard humidistat (See Fig. 12). These terminals areenergized with 24-v. when G thermostat signal is present. (SeeFig. 11, 12 & 13). Alternately, the 24-v. signal may be sourcedfrom the W and C circuit board connections. When using aThermidistat™ Control, Zone Comfort Plus or Comfort ZoneII, the 24-v. signal may be sourced directly from the Thermi-distat™ HUM terminal.e. DEHUMIDIFY CAPABILITY WITH STANDARDHUMIDISTAT CONNECTIONLatent capacities for these units are better than average systems.If increased latent capacity is an application requirement, thecircuit board provides connection terminals for use of astandard humidistat. The unit will detect the humidistat contactsopening on increasing humidity and reduce its airflow toapproximately 80 percent of nominal cooling mode airflow.This reduction will increase the system latent capacity until thehumidity falls to a level which causes the humidistat to close itscontacts. When the contacts close, the airflow will return to 100percent of selected cooling airflow. To activate this mode,remove jumper J1 and wire in a standard humidistat ( See Fig.13).f. DEHUMIDIFY AND SUPER DEHUMIDIFY CAPABILITIESthese models are capable of responding to a signal from indoorsystem control (thermostat, Thermidistat™, zoning control) tooperate in comfort control modes such as Super DehumidifyMode. Consult literature provided with indoor system control todetermine if these operating modes are available, and to seecontrol set up instructions. No special setup or wiring of unit isrequired.50GL & 50JZ SEQUENCE OF OPERATIONa. CONTINUOUS FAN(1.) Thermostat closes circuit R to G—The Blower runs atcontinuous fan airflow.b. COOLING MODE-LOW HUMIDITY(1.) If indoor temperature is above temperature set point andhumidity is below humidity set point, thermostat closescircuits R to G, R to Y/Y2 and R to O—The unit deliverscooling airflow.c. COOLING MODE-DEHUMIDIFICATION(1.) If indoor temperature is above temperature set point andhumidity is above humidity set point, thermostat or Ther-midistat™ closes circuits R to G, R to O, and R to Y/Y2and humidistat or Thermidistat™ opens R to DH—Theunit delivers airflow which is approximately 80 percent ofthe nominal cooling airflow to increase the latent capacityof the system.d. COOLING MODE-SUPER DEHUMIDIFY OPERATION (seequick reference guide)NOTE: The indoor control used, such as a Thermidistat™, mustbe capable of providing Super Dehumidify operation mode andcontrol must be configured as outlined in its installation instruc-tions. Consult indoor control literature to determine if control iscapable of providing Super Dehumidify inputs and for configura-tion instruction.(1.) If the indoor temperature is below the temperature setpoint and the humidity is above the humidity set point, theThermidistat™ closes circuit R to O, opens circuits R toDH and R to G, and cycles circuit R to Y/Y2. If circuit Rto G is closed (24-v.), the motor will deliver airflow at thefull cooling or cooling plus dehumidify mode requestedFig. 12—Humidifier Wiring for 50GL & 50JZA95317HUMIDISTATTO HUMIDIFIERHUMIDIFIER WIRINGHUM 1(C)HUM 2(G)24-VACFig. 13—Humidistat Wiring for De-Humidify Mode-for 50GL & 50JZA95316EASY SELECTBOARD TERMINALBLOCKD HJ1RHUMIDISTATREMOVEJUMPER9