Carrier WEATHERMAKER 48/50AJ Specifications

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.Cata

10Table 7 — Fan Performance — 48AJ,AK,A2,A3040 UnitsTable 8 — Fan Performance — 48AJ,AK041 UnitsAIRFLOW(Cfm)AVAILABLE EXTERNAL STATIC PRESSURE (in. wg

100• Circuit breaker trip. The compressors are protected fromshort circuit by a breaker in the control box. On the 020-050size units there is one brea

101• the selection of a mode for VAV units• economizer differential enthalpy or dry bulb control• return air temperature supply air resetT076 (Outsid

102P126 and P127 alerts may be stored in alarm history but notbroadcast.T128 (Digital Scroll High Discharge Temperature Alert)A128 (Digital Scroll Hig

103will be performed and an alert will be generated. Recovery isautomatic. Reason for error is either a faulty sensor, wiringerror, or damaged input o

104energized (fire shutdown is in effect), or if two fire smokemodes are incorrectly energized at the same time, a fire shut-down mode will occur. Thi

105another Service Test mode is selected. Remove jumper whendone using Service Test if the unit is operating with a thermo-stat. The jumper should onl

106STAGED GAS HEAT BOARD (SCB) — When optionalstaged gas heat is used on CV and VAV units, the SCB board isinstalled and controls operation of the ga

107RED JUMPER WIRE MUST BE ADDEDBETWEEN R AND W1 FOR UNITSEQUIPPED WITH HEAT IN NON-THERMOSTATAPPLICATIONS~~~~~~~~TONEXTPAG EFig. 15 — Typical Main Co

108~~~~~ ~~~Fig. 15 — Typical Main Control Box Wiring Schematic (48/50AJ,AK,AW,AY Units) (cont)a48-8355

109Fig. 16 — Typical Main Control Box Wiring Schematic (48/50A2,A3,A4,A5 Units)a48-8355

11Table 9 — Fan Performance — 48AJ,AK,A2,A3050 UnitsTable 10 — Fan Performance — 48AJ,AK051 UnitsLEGENDBhp — Brake Horsepoweredb — Entering Dry Bulbew

110J6J5J4J2J3J8J9J7Fig. 17 — Typical Auxiliary Control Box Wiring Schematic

111Fig. 18 — Typical 2 Stage Gas Heat Wiring Schematic (Size 051 and 060 Units Shown)a48--8357

112~~TONEXTPAG EFig. 19 — Typical Staged Gas Heat Wiring Schematic (Size 051 and 060 Units Shown)A48-7296

113~~Fig. 19 — Typical Staged Gas Heat Wiring Schematic (Size 051 and 060 Units Shown) (cont)A48-8358

114Fig. 20 — Typical Electric Heat Control Schematic — (50 Series Size 051 and 060 Units Shown)a50-8228

115TONEXTPAG EFig. 21 — Typical Power Schematic (48/50AJ,AK,AW,AY051 and 060 Units Shown)A48-7298

116FROMPREVIOUSPAG EFig. 21 — Typical Power Schematic (48/50AJ,AK,AW,AY051 and 060 Units Shown) (cont)a48-8360

117Fig. 22 — Typical Power Schematic (48/50A2,A3,A4,A5060 Unit Shown)

118SW1SW2OR DEHUMIDIFY SWITCHFig. 23 — Typical Controls Option Wiring Schematica48-8361

119Fig. 24 — Typical Small Chassis Component Location (Size 020-035 Units)a48-8362

12Table 11 — Fan Performance — 48AJ,AK,A2,A3060 UnitsTable 12 — Fan Performance — 50AJ,AK020,025 and 50A2,A3020 UnitsLEGENDBhp — Brake Horsepoweredb —

120Fig. 25 — Typical Large Chassis Component Locations (Size 036-060 Units)A48-7302

121LEGEND AND NOTES FOR FIG. 15-25LEGENDNOTES:1. Factory wiring is in accordance with the National ElectricalCodes. Any field modifications or additio

122Table 120 — Main Control Board (MBB) Inputs and OutputsYAC — Gas Heat UnitPOINT NAMEPOINT DESCRIPTIONI/O POINT NAMEPLUG AND PIN REFERENCESIGNAL PIN

123Table 121 — Economizer Control Board (ECB1) Inputs and OutputsTable 122 — VAV Control Board (ECB2) Inputs and OutputsPOINT NAMEPOINT DESCRIPTIONI/O

124Fig. 27 — Economizer Control Board (ECB1) and VAV Control Board (ECB2)A48-7706

125Table 123 — Staged Gas Control Board (SCB) Inputs and OutputsPOINT NAMEPOINT DESCRIPTIONI/O POINT NAMEPLUG AND PIN REFERENCESIGNAL PIN(S) PORT STAT

126Table 124 — RXB Control Board (EXB2) Inputs and OutputsNOTE: Rooftop control board (RXB) is required for digital scroll com-pressor or Humidi-MiZer

127Table 125 — Controls Expansion Board (CEM) InputsPOINT NAMEPOINT DESCRIPTIONI/O POINT NAMEPLUG AND PIN REFERENCESIGNAL PIN(S) PORT STATEINPUTSSFS S

128Table 126 — IGC Board Inputs and OutputsSCROLLING MARQUEE — This device is the keypad in-terface used to access the control information, read senso

129Table 127 — VFD Terminal DesignationsPOWER EXHAUST — The units can be equipped with anoptional power exhaust system. The power exhaust fans areforw

13Table 13 — Fan Performance — 50AJ,AK027,030 and 50A2,A3025-030 UnitsTable 14 — Fan Performance — 50AJ,AKA2,A3035 UnitsLEGENDBhp — Brake Horsepowered

130a pressure transducer connected to the liquid line. On 48/50A020-035 units, one fan will be controlled. On 48/50A036-060 units, two fans will be co

131Table 128 — Field Connection Terminal StripsTERMINALBOARDTERMINALNO.DESCRIPTION TYPETB-1 - POWER CONNECTION OR DISCONNECT (in Main Control Box)TB11

132Green LED — The boards also have a green LED, which isthe indicator of the operation of the LEN communications,which is used for communications bet

133CCN WEBORNETWORK OPTIONSREMOTECCN SITETELINKNON CARRIER HVAC EQUIPMENTBRIDGE(RECOM-MENDED)CIDROOFTOP UNIT COMFORTID AIR TERMINALCIDCID

134SERVICEService Access — All unit components can be reachedthrough clearly labelled hinged access doors. These doors arenot equipped with tiebacks,

135COMBUSTION-AIR BLOWER — Clean periodically to as-sure proper airflow and heating efficiency. Inspect blowerwheel every fall and periodically during

13611. Ensure surfaces are not allowed to dry before rinsing.Reapplying cleaner as needed to ensure 10-minute satura-tion is achieved.12. Thoroughly r

1377. Outside of the unit, assemble the flex members to the cen-ter drive shaft with 4 bolts and nuts. The flex membershave collars that need to be in

138Condenser-Fan AdjustmentNOTE: Condenser fans on size 060 MCHX units are notadjustable.1. Turn off unit power supply.2. Remove fan guard.3. Loosen f

13920 Ton MCHX CIRCUIT A Charging ChartAll Compressors on a Circuit Must be OperatingAll Outdoor Fans Must be Operating7075808590951001051101151201251

14Table 15 — Fan Performance — 50AJ,AK036 UnitsTable 16 — Fan Performance — 50AJ,AK,A2,A3040 UnitsLEGENDBhp — Brake Horsepoweredb — Entering Dry Bulbe

140Fig. 45 — Charging Chart — 48/50A2,A3,A4,A5025 and 027 with R-410A Refrigerant LEGENDMCHX— Microchannel Heat ExchangerSST

14130 Ton MCHX CIRCUIT A Charging ChartAll Compressors on a Circuit Must be OperatingAll Outdoor Fans M ust be Operating707580859095100105110115120125

14235 Ton MCHX CIRCUIT A Charging ChartAll Compressors on a Circuit Must be OperatingAll Outdoor Fans Must be Operating8590951001051101151201251301351

14340 Ton MCHX Charging ChartAll Co mp re ssors on a Circuit Must be OperatingAll Outdoor Fans Must be Operating70758085909510010511011512012513013514

14460 Ton MCHX CIRCUIT A Charging ChartAll Compressors on a Circuit M ust be OperatingAll Outdoor Fans Must be Operating707580859095100105110115120125

145Main Burners — For all applications, main burners arefactory set and should require no adjustment.MAIN BURNER REMOVAL (Fig. 52)1. Shut off (field-s

146APPENDIX A — LOCAL DISPLAY TABLESMODE — RUN STATUSITEM EXPANSION RANGE UNITS CCN POINT WRITE STATUS PAGE NO.VIEW AUTO VIEW OF RUN STATUSHVAC ascii

147APPENDIX A — LOCAL DISPLAY TABLES (cont)MODE — RUN STATUS (cont)MODE — SERVICE TESTITEM EXPANSION RANGE UNITS CCN POINT WRITE STATUS PAGE NO.TMGD T

148APPENDIX A — LOCAL DISPLAY TABLES (cont)MODE — TEMPERATURESMODE — PRESSURESMODE — SET POINTSITEM EXPANSION RANGE UNITS CCN POINT WRITE STATUSAIR.T

149APPENDIX A — LOCAL DISPLAY TABLES (cont)MODE — INPUTS*The display text changes depending on the remote switch configuration (ConfigurationUNITRM.

15Table 17 — Fan Performance — 50AJ,AK041 UnitsTable 18 — Fan Performance — 50AJ,AK,A2,A3050 UnitsAIRFLOW(Cfm)AVAILABLE EXTERNAL STATIC PRESSURE (in.

150APPENDIX A — LOCAL DISPLAY TABLES (cont)MODE — OUTPUTSMODE — CONFIGURATIONITEM EXPANSION RANGE UNITS CCN POINT WRITE STATUSFANS FANSS.FAN Supply F

151APPENDIX A — LOCAL DISPLAY TABLES (cont)MODE — CONFIGURATION (cont)ITEM EXPANSION RANGE UNITS CCN POINT DEFAULT PAGE NO.COOL COOLING CONFIGURATION

152APPENDIX A — LOCAL DISPLAY TABLES (cont)MODE — CONFIGURATION (cont)ITEM EXPANSION RANGE UNITS CCN POINT DEFAULT PAGE NO.ECON ECONOMIZER CONFIGURATI

153APPENDIX A — LOCAL DISPLAY TABLES (cont)MODE — CONFIGURATION (cont)ITEM EXPANSION RANGE UNITS CCN POINT DEFAULT PAGE NO.IAQ INDOOR AIR QUALITY CFG.

154APPENDIX A — LOCAL DISPLAY TABLES (cont)MODE — CONFIGURATION (cont)MODE — TIME CLOCKITEM EXPANSION RANGE UNITS CCN POINT DEFAULT PAGE NO.TRIM SENSO

155APPENDIX A — LOCAL DISPLAY TABLES (cont)MODE — OPERATING MODESMODE — ALARMSITEM EXPANSION RANGE UNITS CCN POINTSYS.M ascii string spelling out the

156APPENDIX B — CCN TABLESAll A Series units with ComfortLink controls have a port forinterface with the Carrier Comfort Network® (CCN) system.On TB3

157APPENDIX B — CCN TABLES (cont)STATUS DISPLAY TABLES (cont)TABLE DISPLAY NAME RANGE UNITS POINT NAME WRITE STATUSGENERALOccupied ? Yes/No OCCUPIED f

158APPENDIX B — CCN TABLES (cont)STATUS DISPLAY TABLES (cont)TABLE DISPLAY NAME RANGE UNITS POINT NAME WRITE STATUSTEMPSAir Temp Lvg Supply Fan dF SAT

159APPENDIX B — CCN TABLES (cont)SET POINT TABLECONFIG TABLESTABLE NAME RANGE UNITS POINT NAME DEFAULTSET_PNTOccupied Heat Setpoint 40-99 dF OHSP 68Oc

16Table 19 — Fan Performance — 50AJ,AK051 UnitsTable 20 — Fan Performance — 50AJ,AK,A2,A3060 UnitsAIRFLOW(Cfm)AVAILABLE EXTERNAL STATIC PRESSURE (in.

160APPENDIX B — CCN TABLES (cont)CONFIG TABLES (cont)SERVICE-CONFIG TABLESTABLE NAME RANGE UNITS POINT NAME DEFAULTSCHEDOVRSchedule Number 0-99 SCHEDN

161APPENDIX B — CCN TABLES (cont)SERVICE-CONFIG TABLES (cont)TABLE NAME RANGE UNITS POINT NAME DEFAULTCOOLCapacity Threshold Adjust –10 -> 10 Z_GAI

162APPENDIX B — CCN TABLES (cont)SERVICE-CONFIG TABLES (cont)TABLE NAME RANGE UNITS POINT NAME DEFAULTT24_CFGEconomizer Installed ? Yes/No ECON_ENA Ye

163APPENDIX B — CCN TABLES (cont)SERVICE-CONFIG TABLES (cont)TABLE NAME RANGE UNITS POINT NAME DEFAULTTRIMAir Temp Lvg SF Trim –10 - 10 ^F SAT_TRIM 0R

164APPENDIX B — CCN TABLES (cont)MAINTENANCE DISPLAY TABLESTABLE DISPLAY NAME RANGE UNITS POINT NAME WRITE STATUSALARMS01Active Alarm ascii ALARM_01-

165APPENDIX B — CCN TABLES (cont)MAINTENANCE DISPLAY TABLES (cont)TABLE DISPLAY NAME RANGE UNITS POINT NAME WRITE STATUSECON_MINEcono Damper Command P

166APPENDIX B — CCN TABLES (cont)MAINTENANCE DISPLAY TABLES (cont)TABLE DISPLAY NAME RANGE UNITS POINT NAME WRITE STATUST24_DIAGEconomizer Installed?

167APPENDIX B — CCN TABLES (cont)MAINTENANCE DISPLAY TABLES (cont)TABLE DISPLAY NAME RANGE UNITS POINT NAME WRITE STATUSOCCDEFMECurrent Day, Time &

168APPENDIX B — CCN TABLES (cont)MAINTENANCE DISPLAY TABLES (cont)TABLE DISPLAY NAME RANGE UNITS POINT NAME WRITE STATUSSUMZCooling Control Point dF C

169APPENDIX B — CCN TABLES (cont)TIME SCHEDULE CONFIG TABLEAllowable Entries: Day not selected = 0 Day selected = 1DAY FLAGSMTWTFSSHOCCUPIEDTIMEUNOCCU

17Table 21 — Fan Performance — 48AW,AY020,025 and 48A4,A5020 UnitsTable 22 — Fan Performance — 48AW,AY027,030 and 48A4,A5025-030 UnitsLEGENDBhp — Brak

170APPENDIX C — VFD INFORMATIONOn variable air volume units with optional VFD, the supplyfan speed is controlled by a 3-phase VFD. The VFD is locatedi

171APPENDIX C — VFD INFORMATION (cont)Table B — VFD ConfigurationsVFD Operation — The VFD keypad is shown in Fig. B.The function of SOFT KEYS 1 and 2

172APPENDIX C — VFD INFORMATION (cont)4. Use the UP or DOWN keys to highlight the desiredparameter and press EDIT (SOFT KEY 2).5. Use the UP or DOWN k

173APPENDIX C — VFD INFORMATION (cont)CHANGED PARAMETERS MODE — The Changed Param-eters mode is used to view and edit recently changed parameterson th

174APPENDIX C — VFD INFORMATION (cont)7. Use the UP or DOWN keys to highlight DATE FOR-MAT and press SEL (SOFT KEY 2). Use the UP orDOWN keys to chang

175APPENDIX C — VFD INFORMATION (cont)Table C — Fault CodesFAULT CODEFAULT NAME IN PANELDESCRIPTION AND RECOMMENDED CORRECTIVE ACTION1 OVERCURRENTOutp

176APPENDIX C — VFD INFORMATION (cont)Table D — Alarm Codes*This alarm is not indicated by a relay output, even when the relay output is configured to

177APPENDIX C — VFD INFORMATION (cont)MAIN FAN REPLACEMENT — The main cooling fan ofthe VFD has a life span of about 60,000 operating hours atmaxi

178APPENDIX C — VFD INFORMATION (cont)Fig. F — Internal Enclosure Fan ReplacementA48-7716

179APPENDIX D — MODE SELECTION PROCESSThe following section is to be used in conjunction withFig. 4 on page 34. To help determine why the unit control

18Table 23 — Fan Performance — 48AW,AY,A4,A5035 UnitsTable 24 — Fan Performance — 48AW,AY036 UnitsSee legend on page17.AIRFLOW(Cfm)AVAILABLE EXTERNAL

180APPENDIX E — UPC OPEN CONTROLLERThe following section is used to configure the UPC Open.The UPC Open controller is mounted in a separate enclosureb

181APPENDIX E — UPC OPEN CONTROLLER (cont)Configuring the BAS Port for BACnet MS/TP — Use the same baud rate and communication settingsfor all control

182APPENDIX E — UPC OPEN CONTROLLER (cont)To install a BT485 terminator, push the BT485 terminator,on to the BT485 connector located near the BACnet c

183APPENDIX E — UPC OPEN CONTROLLER (cont)Table I — Open System Wiring Specifications and Recommended Vendors LEGENDLocal

184APPENDIX E — UPC OPEN CONTROLLER (cont)Configuring the UPC Open Controller's Prop-erties — The UPC Open device and ComfortLink controlsmust b

185APPENDIX E — UPC OPEN CONTROLLER (cont)NETWORK POINTS LISTSee legend on page 191.POINT DESCRIPTIONCCNPOINTNAMEREAD/WRITEUNITSDEFAULTVALUERANGEBACNE

186APPENDIX E — UPC OPEN CONTROLLER (cont)NETWORK POINTS LIST (cont)See legend on page 191.POINT DESCRIPTIONCCNPOINTNAMEREAD/WRITEUNITSDEFAULTVALUERAN

187APPENDIX E — UPC OPEN CONTROLLER (cont)NETWORK POINTS LIST (cont)See legend on page 191.POINT DESCRIPTIONCCNPOINTNAMEREAD/WRITEUNITSDEFAULTVALUERAN

188APPENDIX E — UPC OPEN CONTROLLER (cont)NETWORK POINTS LIST (cont)See legend on page 191.POINT DESCRIPTIONCCNPOINTNAMEREAD/WRITEUNITSDEFAULTVALUERAN

189APPENDIX E — UPC OPEN CONTROLLER (cont)NETWORK POINTS LIST (cont)See legend on page 191.POINT DESCRIPTIONCCNPOINTNAMEREAD/WRITEUNITSDEFAULTVALUERAN

19Table 25 — Fan Performance — 48AW,AY,A4,A5040 UnitsTable 26 — Fan Performance — 48AW,AY041 UnitsSee legend on page17.AIRFLOW(Cfm)AVAILABLE EXTERNAL

190APPENDIX E — UPC OPEN CONTROLLER (cont)NETWORK POINTS LIST (cont)See legend on page 191.POINT DESCRIPTIONCCNPOINTNAMEREAD/WRITEUNITSDEFAULTVALUERAN

191APPENDIX E — UPC OPEN CONTROLLER (cont)NETWORK POINTS LIST (cont) LEGENDPOINT DESCRIPTIONCCNPOINTNAMEREAD/WRITEUNITSD

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.Cata

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.Cata

CL-2- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

CL-3ITEM EXPANSION RANGE DEFAULT ENTRYECON ECONOMIZER CONFIGURATIONEC.EN Economizer Installed? Yes/No YesEC.MN Economizer Min.Position 0 - 100 % 5E

CL-4- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

CL-5ITEM EXPANSION RANGE DEFAULT ENTRYALLM ALERT LIMIT CONFIG.SP.L.O SPT lo alert limit/occ –10-245 dF 60SP.H.O SPT hi alert limit/occ –10-245 dF 85

2CONTENTS (cont)PageIndoor Air Quality Control. . . . . . . . . . . . . . . . . . . . . . . . . . 69•OPERATION• SETTING UP THE SYSTEM• PRE-OCCUPANCY P

20Table 27 — Fan Performance — 48AW,AY,A4,A5050 UnitsTable 28 — Fan Performance — 48AW,AY051 UnitsAIRFLOW(Cfm)AVAILABLE EXTERNAL STATIC PRESSURE (in.

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.Cata

21Table 29 — Fan Performance — 48AW,AY,A4,A5060 UnitsTable 30 — Fan Performance — 50AW,AY020,025 and 50A4,A5020 UnitsLEGENDBhp — Brake Horsepoweredb —

22Table 31 — Fan Performance — 50AW,AY027,030 and 50A4,A5025-030 UnitsTable 32 — Fan Performance — 50AW,AY,A4,A5035 UnitsLEGENDBhp — Brake Horsepowere

23Table 33 — Fan Performance — 50AW,AY036 UnitsTable 34 — Fan Performance — 50AW,AY,A4,A5040 UnitsLEGENDBhp — Brake Horsepoweredb — Entering Dry Bulbe

24Table 35 — Fan Performance — 50AW,AY041 UnitsTable 36 — Fan Performance — 50AW,AY,A4,A5050 UnitsLEGENDBhp — Brake Horsepoweredb — Entering Dry Bulbe

25Table 37 — Fan Performance — 50AW,AY051 UnitsTable 38 — Fan Performance — 50AW,AY,A4,A5060 UnitsAIRFLOW(Cfm)AVAILABLE EXTERNAL STATIC PRESSURE (in.

26Table 39 — Motor LimitationsLEGENDNOTES:1. Extensive motor and electrical testing on the Carrier units has ensured thatthe full horsepower range of

27Table 41 — Air Quantity Limits (50AJ,AK,AW,AY,A2,A3,A4,A5)*Operation at these levels may be limited by entering evaporator air wet bulb temperatures

284. See the Economizer Options section on this page for ad-ditional economizer option configurations.5. See the Exhaust Options section on this page

29to go into Edit mode. The first two digits of the 00.00 willstart flashing. Use the UP or DOWN key to display thecorrect value for hours, in 24-hour

3GENERALThis book contains Start-Up, Controls Operation, Trouble-shooting and Service information for the 48/50A Seriesrooftop units. See Table 1. The

30Table 42 — Service TestTHIRD PARTY CONTROLThermostat — The method of control would be throughthe thermostat inputs:Y1 = first stage coolingY1 and Y

31and when ON, the control sets a capacity limit to the Configu-rationDMD.LD.L.S2 set point. If both switches are ON, InputsGEN.IDL.S2 is usedas t

32NOTE: Configuration OAQ.U is used in the calculation of thetrip point for override and can be found under Configura-tion IAQAQ.SP.IQ.A.C = 3 (4 to

33are two possible text displays for this mode, one is normal runmode and the other occurs if one of the following fire-smokemodes is present: smoke p

34System Mode = OFF? Inputs -> FIRE -> FSD in alarm? HVAC Mode = OFF (Fire Shutdown) HVAC Mode = OFF (Disabled) Unit not in factory test AND f

35Unit Configuration Submenu — The UNIT sub-menu under the Configuration mode of the local displaycontains general unit configuration items. The sub-

36Condenser Type (CND.T) — This configuration specifies thetype of condenser installed in the unit. Configuration CND.T isset to 0 if the condenser is

37Cooling Control — When mechanical cooling is required,the A Series ComfortLink control system has the capability tocontrol the staging of the compre

38• 1 = SPT RESETSpace temperature will be used as the reset control variablealong with both RTIO and LIMT in the calculation of thefinal amount of re

39Fan-Off Delay, Mech Cool (C.FOD) — After a mechanicalcooling cycle has ended, this is the delay in seconds that thesupply fan will continue to opera

4Pressing the and keys simultaneouslyat any time will display an expanded text description of the four-character point name. The expanded descript

40reads ON, an alert is generated. This will indicate that a com-pressor contactor has failed closed. In this case, a special mode“Compressor Stuck on

41between the calling out of a heating or cooling mode at alltimes.NOTE: There is a sub-menu at the local display (Run StatusTRIP) that allows the us

42Timeguards — In addition to the set points and offsets whichdetermine the trip points for bringing on and bringing off coolmodes there is a timeguar

43requested number of compressors is changed from 4 to 3. Ifanother compressor faults, then both Lo Cool and Hi Coolrequested number of compressors ar

44Table 52 — Staging Sequence without Hot Gas Bypass — 48/50AK,AY020-027 and Multi-Stage 48/50AJ,AW020-027Table 53 — Capacity Control Staging Options

45Table 56 — Staging Sequence with Hot Gas Bypass — 48/50AK,AY030-060*With minimum load valve ON.Table 57 — 2-Stage Sequence — 48/50A2,A4020-027Table

46Table 61 — Staging Sequence without Hot Gas Bypass — 48/50A3,A5030-060 and Multi-Stage 48/50A2,A4030-060Table 62 — Staging Sequence with Hot Gas Byp

47Next Stage EDT Increase (SUB.R) — This variable repre-sents (if subtracting a stage of cooling) how much thetemperature should rise in degrees dep

48Z Calculation — For the “Z” calculation, the control attemptsto determine the entering and the leaving-air temperature of theevaporator coil and bas

49Table 65 — Demand Limit ConfigurationDemand Limit Select (DM.L.S) — This configuration deter-mines the type of demand limiting.• 0 = NONE — Demand L

5Operation — All units are shipped from the factory withthe scrolling marquee display, which is located in the main con-trol box. See Fig. 1. In addit

50unit size (ConfigurationUNITSIZE) is 60 tons and thecondenser heat exchanger type (ConfigurationUNITCND.T) is RTPF (round tube plate fin). This

51Economizer Mechanical Cooling Delay — This type of me-chanical cooling delay is relevant to the all machine controltypes.If the economizer is able t

52Fan-Off Delay, Gas Heat (G. F O D ) — This configuration isthe delay in seconds, after a gas heat mode has ended(HT.CF=2,3) that the control will co

53Table 68 — Heat/Cool Set Point OffsetsHeat Trend Demand Level (H.T.LV) — This is the change indemand that must be seen within the time period specif

54Table 70 — Staged Gas Configuration*Some configurations are model number dependent.Staged Gas Heating LogicIf the HVAC mode is HIGH HEAT: • The supp

555 seconds. If the burners do not light, there is a 22-second delaybefore another 5-second attempt is made. If the burners still donot light, this se

56Table 75 — Staged Gas Heat Control Steps (ConfigurationHEAT SG.CTHT.ST = 3)Table 76 — Staged Gas Heat Control Steps (ConfigurationHEAT SG.CTHT

57The Morning Warm Up Period is CCN linkage mode “2”and is relayed in the following conditions:• Temperature Compensated Start Mode is active AND Heat

58maintains an optimal duct static pressure set point based on theactual load conditions in the space. This can result in a signifi-cant reduction in

59Static Pressure Reset Limit (SP.LM) — This option definesthe maximum amount of static pressure reset that is allowed.This is sometimes called a “cla

6Table 2 — Scrolling Marquee Menu Display Structure(ComfortLink Display Modes)RUNSTATUSSERVICETESTTEMPERATURES PRESSURES SETPOINTS INPUTS OUTPUTS CONF

60Table 78 — Static Pressure Control Configuration* Some defaults are model number dependent.† 33-67 when CV.FD = Yes.** 67 when CV.FD = Yes.Table 7

61Table 80 — Fan Status Monitoring ConfigurationTable 81 — Dirty Filter Switch PointsMonitoring of the filter status switch is disabled in theService

62The control shall test for a jammed actuator as follows:• If the actuator has stopped moving and the reported position(ECONOPOS) is not within ± 3%

63OA.E.C = 2 Honeywell B CurveOA.E.C = 3 Honeywell C CurveOA.E.C = 4 Honeywell D CurveOA.E.C = 5 custom enthalpy curveIf the user selects OA.E.C = 5,

64The Unoccupied Economizer Free Cooling Mode will stopwhen either of the following conditions are true:{SPT < OCSP} OR {SPT < (OAT + 3)} where

65ECONOMIZER OPERATION CONFIGURATION — Theconfiguration items in the E.CFG menu group affect howthe economizer modulates when attempting to follow ane

66If either circuit’s suction pressure drops to within 5 psigof the low suction pressure trip point, the control will startadding reset to the economi

67Power Exhaust on Setp.1 (BP.P2) — When configured forbuilding pressure control type BP.CF = 1 (constant volume two-stage control), the control will

68Table 85 — Power Exhaust Staging (BP.CF = 1) Table 86 — Power Exhaust Staging (BP.CF = 2) • If building pressure (PressuresAIR.PBP) is less thanth

69air damper), turning on the power exhaust and shutting downthe indoor fan decrease pressure in the space.Smoke Purge Mode — This mode attempts to dr

7GENERICS STATUS DISPLAY TABLE — The GENERICSpoints table allows the service/installer the ability to create acustom table in which up to 20 points f

70quality sensors are IQ.R.L, IQ.R.H, OQ.R.L and OQ.R.H. Thebounds represent the PPM corresponding to 4 mA (low) and20 mA (high) for IAQ and OAQ, resp

71operation and turn it on (if off) during both the occupiedand unoccupied period.OAQ 4-20 mA Sensor Config (ConfigurationIAQAQ.CFOQ.A.C) — This is

72Dehumidification Sensor (D.SEN) — The sensor can be con-figured for the following settings:• D.SEN = 1 — Initiated by return air relative humidityse

73Table 88 — Dehumidification ConfigurationDehumidification and Reheat Control — If a dehumidifica-tion mode is initiated, the rooftop will attempt to

74CCN OAT Broadcast (OAT.B) — If this configuration is setto ON, the control will periodically broadcast its outside-airtemperature at a rate of once

75Table 89 — CCN Configuration* For units equipped with optional UPC, the CCN Baud Rate must be set to 3.Supply Duct Pressure Low Alert Limit (SP.L) —

76Table 90 — Alert Limit ConfigurationTable 91 — Sensor Trim ConfigurationThe defaults for this switch logic section will not normallyneed changing. H

77Table 92 — Switch Logic ConfigurationTable 93 — Display ConfigurationRemote Control Switch Input — The remote switchinput is located on the ECB-1 bo

78Table 95 — Remote Switch Logic ConfigurationTIME CLOCK CONFIGURATIONThis section describes each Time Clock menu item. Notevery point will need to be

79DAYLIGHT SAVINGS START (DS.ST) — This submenuconfigures the start date and time for daylight savings.Daylight Savings Start Month (DS.STST.MN) — T

8Table 3 — Fan Performance — 48AJ,AK020,025 and 48A2,A3020 UnitsTable 4 — Fan Performance — 48AJ,AK027,030 and 48A2,A3025-030 UnitsLEGENDBhp — Brake

80TROUBLESHOOTINGThe scrolling marquee display shows the actual operatingconditions of the unit while it is running. If there are alarms orthere have

81Table 97 — Cooling Service Analysis LEGENDPROBLEM SOLUTIONCOMPRESSOR DOES NOT RUNActive AlarmCheck active alarms using local display.Contactor

82Table 97 — Cooling Service Analysis (cont) LEGENDPROBLEM SOLUTIONCOMPRESSOR RUNNING BUT COOLING INSUFFICIENTSuction Pressure

83Table 98 — Gas Heating Service AnalysisTable 99 — Electric Heat Service AnalysisPROBLEM CAUSE REMEDYBurners Will Not Ignite. Active alarm. Check act

84Fig. 14 — IGC Service Analysis Logic LEGENDNOTE: Thermostat Fan Switch in the“AUTO” position.IDM — Induced-Draft MotorIGC — Integ

85Table 100 — 5K Thermistor Temperature vs. Resistance (SCT Sensors) (English)TEMP(F)VOLTAGEDROP(V)RESISTANCE(Ohms)–25 3.699 98,010–24 3.689 94,707–23

86Table 101 — 5K Thermistor Temperature vs. Resistance (SCT Sensors) (SI)Table 102 — 6K Thermistor Temperature vs. Resistance (SI and English)TEMP(F)T

87Table 103 — 10K Thermistor vs. Resistance (T55, T56, OAT, RAT, EDT, LAT Sensors) (English)TEMP(F)VOLTAGEDROP (V)RESISTANCE(Ohms)–25 4.758 196,453–24

88Table 104 — 10K Thermistor vs. Resistance (T55, T56, OAT, RAT, EDT, LAT Sensors) (SI)Table 105 — Digital Scroll Discharge ThermistorTEMP(C)VOLTAGEDR

89Table 106 — Suction Pressure Transducer Pressure (PSIG) vs. Voltage (SP-A, SP-B, SP.XR=0, 48/50AJ,AK,AW,AY Units Only)PRESSURE(PSIG)VOLTAG EDROP (V

9Table 5 — Fan Performance — 48AJ,AK,A2,A3035 UnitsTable 6 — Fan Performance — 48AJ,AK036 UnitsLEGENDBhp — Brake Horsepoweredb — Entering Dry Bulbewb

90Table 107 — Suction Pressure Transducer Pressure (PSIG) vs. Voltage (SP-A, SP-B, SP.XR = 1, 48/50AJ,AK,AW,AY Units Only)PRESSURE(PSIG)VOLTAG EDROP (

91Table 108 — Suction Pressure Transducer (PSIG) vs. Voltage (SP-A, SP-B, 48/50A2,A3,A4,A5 Units Only)PRESSURE(PSIG)VOLTAGEDROP (V) PRESSURE(PSIG)VOLT

92Table 109 — Discharge Pressure Transducer (PSIG) vs. Voltage (DP-A, DP-B,48/50A2,A3,A4,A5 Units Only)PRESSURE(PSIG)VOLTAG EDROP (V)PRESSURE(PSIG)VOL

93Table 109 — Discharge Pressure Transducer (PSIG) vs. Voltage (DP-A, DP-B,48/50A2,A3,A4,A5 Units Only) (cont)PRESSURE(PSIG)VOLTAG EDROP (V)PRESSURE(P

94Forcing Inputs and Outputs — Many variables maybe forced both from the CCN and directly at the local display.This can be useful during diagnostic te

95Cap Threshold Subtracting (Z.MIN) — This parameter isused in the calculation of SMZ and is calculated as follows:Z.MIN = ConfigurationCOOLZ.GN * (

96Table 112 — Cooling Information Display TableTable 113 — Mode Trip Helper Display TableTable 114 — CCN/Linkage Display TableTable 115 — Compressor R

97Table 117 — Time Guard Display TableTable 118 — Software Version Numbers Display TableAlarms and Alerts — There are a variety of differentalerts and

98Table 119 — Alert and Alarm CodesALARM ORALERT NUMBERDESCRIPTION ACTION TAKEN BY CONTROLRESETMETHODPROBABLE CAUSEA051 Circuit A, Compressor 1 Stuck

99Table 119 — Alert and Alarm Codes (cont) LEGENDFor 48/50A2,A3,A4,A5 units:• Compressor internal o