Carrier 48AK Installation, Start-up And Service Instructions Manual

Also see for 48AJ: Installation instructions Operation and service guide Started guide Operating and service guide

Contents

30Table 5 — Controls Options and Configurations (Non-Thermostat Applications)LEGEND*With DIP Switch No. 5 configured to OPEN (Occupied Heat Enabled).NOTE: Space temperature sensor and remote start/stop switch are field-supplied.STAGED GAS UNIT APPLICATIONS — The rooftop unitsmay be ordered with an optional factory-installed staged gascontrol system that monitors heating operation of the rooftopunit.Install Supply-Air Thermistors (Staged Gas Units Only) —Supply-air thermistors are a field-installed factory-providedcomponent. Three supply-air thermistors are shipped withstaged gas units and are inside the heating section. Thermistorwires must be connected to SGC (staged gas controller) in theheating section. See Table 6 and Fig 24. The supply-air ther-mistors should be located in the supply duct with the followingcriteria:• downstream of the heat exchanger cells• equally spaced as far as possible from the heat exchangercells• a duct location where none of the supply air thermistorsare within sight of the heat exchanger cells• a duct location with good mixed supply air portion of theunit.THERMISTORS — All units are equipped with a supply airthermistor (SAT) located in the supply fan discharge and anoutdoor air thermistor (OAT) located in the outdoor air hood.Variable air volume (VAV) units are supplied with a return airthermistor (RAT) located on the return air damper support.CONSTANT VOLUME APPLICATIONS — The units, asshipped, are operable as stand-alone units, using either a stan-dard (mechanical or electronic) 2-stage heat, 2-stage cool ther-mostat, or with an electronic room sensor and a timeclock toestablish unit start and stop times.With a standard thermostat (programmable is optional),heating and cooling operation is set by space temperature.With a space sensor and timeclock, the machine will operateat default values unless they are changed using appropriate in-put devices. The space sensor senses space temperature andmay be equipped with a timed override feature, which allowsunit operation during unoccupied periods.The space sensors may be used in multiples of 4 or 9 toachieve space temperature averaging. The use of a space sensoralso allows the unit to be turned on and off from a remotesignal.Table 6 — Thermistor DesignationsUNIT CONFIGURATION DEFAULT COOLING DEFAULT HEATINGCV or VAV Unit with SPT Sensor Unoccupied Cooling — 90 F (32 C) (SPT)Occupied Cooling — NAUnoccupied Heating — 55 F (13 C) (SPT)Occupied Heating — NACV Unit with SPT Sensor and RemoteStart/Stop SwitchUnoccupied Cooling — 90 F (32 C) (SPT)Occupied Cooling — 78 F (26 C) (SPT)Unoccupied Heating — 55 F (13 C) (SPT)Occupied Heating — 68 F (20 C) (SPT)VAV Unit Remote Start/Stop Switch Only Unoccupied Cooling — 90 F (32 C)(SPT)Occupied Cooling — 55 F (13 C) SPT)Unoccupied Heating — 55 F (13 C) (RAT)Occupied Heating — 68 F (20 C) (RAT)*VAV Unit with SPT Sensor and RemoteStart/Stop SwitchUnoccupied Cooling — 90 F (32 C) (SPT)Occupied Cooling — 55 F (13 C) (SAT)Unoccupied Heating — 55 F (13C) (SPT)Occupied Heating — 68 F (20 C) (RAT)*CV — Constant VolumeNA — Not AvailableRAT — Return-Air TemperatureSAT — Supply-Air TemperatureSPT Space TemperatureVAV — Variable Air VolumeIMPORTANT: An accessory field-supplied Navigator dis-play module is required for all staged gas control units.THERMISTORPINCONNECTIONPOINTFUNCTION AND LOCATIONPART NO.ThermistorsSAT 1 J8 – 1,2 (SGC) Supply Air Thermistor (SAT) — Inserted into supply sectionunderneath the gas heat section (factory-provided, field-installed)HH79NZ016SAT 2 J8 – 3,4 (SGC) Supply Air Thermistor (SAT) — Inserted into supply sectionunderneath the gas heat section (factory-provided, field-installed)SAT 3 J8 – 5,6 (SGC) Supply Air Thermistor (SAT) — Inserted into supply sectionunderneath the gas heat section (factory-provided, field-installed)