Carrier 50HCQ07 Installation Instructions Manual

43Table 18 — Enthalpy Operation, No Demand Controlled Ventilation (DCV) (CO2 Sensor) — 2 Speed Fan*With 2SP FAN DELAY (Advanced Setup Menu) when in theeconomizing mode there is a delay for the high speed fan to try tosatisfy the call for second stage cooling by turning on the fan to highand opening the OA damper 100% before the first stage mechanicalcooling is enabled.† With stage 3 delay (STG3 DLY) in Advanced setup menu, secondstage of mechanical cooling Y2-O can be turned on after the delay if thecalls for Y1-I and Y2-I have not been satisfied.Table 19 — Enthalpy Operation, with Demand Controlled Ventilation (DCV) (CO 2 Sensor) — 2 Speed Fan*With 2SP FAN DELAY (Advanced Setup Menu) when in theeconomizing mode there is a delay for the high speed fan to try tosatisfy the call for second stage cooling by turning on the fan to highand opening the OA damper 100% before the first stage mechanicalcooling is enabled.† With stage 3 delay (STG3 DLY) in Advanced setup menu, secondstage of mechanical cooling Y2-O can be turned on after the delay if thecalls for Y1-I and Y2-I have not been satisfied.Table 20 — Single Enthalpy and Dual Enthalpy High Limit CurvesEnthalpy SettingsWhen the OA temperature, enthalpy and dew point are belowthe respective setpoints, the Outdoor Air can be used for econ-omizing. Figure 50 shows the new single enthalpy boundariesin the W7220. There are 5 boundaries (setpoints ES1 throughES5), which are defined by dry bulb temperature, enthalpy anddew point.Refer to Table 20 for ENTH CURVE setpoint values.The W7220 calculates the enthalpy and dew point using theOA temperature and humidity input from the OA enthalpy sen-sor. When the OA temperature, OA humidity and OA dewpoint are all below the selected boundary, the economizer setsthe economizing mode to YES, economizing is available.When all of the OA conditions are above the selected bound-ary, the conditions are not good to economize and the mode isset to NO.Figure 50 shows the 5 current boundaries. There is also a highlimit boundary for differential enthalpy. The high limit bound-ary is ES1 when there are no stages of mechanical cooling en-ergized and HL (high limit) when a compressor stage isenergized.DCVOUTSIDE AIRGOOD TOECONOMIZE?Y1-I Y2-I FAN SPEED Y1-O Y2-O OCCUPIED UNOCCUPIEDNoneNoOff Off Low 0-v/Off 0-v/Off MIN POS L ClosedOn Off Low 24-v/On 0-v/Off MIN POS L ClosedOn On High 24-v/On 24-v/On MIN POS H ClosedYesOff Off Low 0-v/Off 0-v/Off MIN POS L ClosedOn Off Low 0-v/Off 0-v/Off MIN POS L to Full-Open Closed to Full-OpenOn On High DELAY*24-v/On 0-v/Off† MIN POS H to Full-Open Closed to Full-OpenDCVOUTSIDE AIRGOOD TOECONOMIZE?Y1-I Y2-I FAN SPEED Y1-O Y2-O OCCUPIED UNOCCUPIEDBelow SetNoOff Off Low 0-v/Off 0-v/Off VENTMIN L ClosedOn Off Low 24-v/On 0-v/Off VENTMIN L ClosedOn On High 24-v/On 24-v/On VENTMIN H ClosedYesOff Off Low 0-v/Off 0-v/Off VENTMIN L ClosedOn Off Low 0-v/Off 0-v/Off VENTMIN L to Full-Open Closed to Full-OpenOn On High 24-v/On 0-v/Off† VENTMIN H to Full-Open Closed to Full-OpenAbove SetNoOff Off Low 0-v/Off 0-v/Off VENTMIN L to VENTMAX ClosedOn Off Low 24-v/On 0-v/Off VENTMIN L to VENTMAX ClosedOn On High 24-v/On 24-v/On VENTMIN H to VENTMAX ClosedYesOff Off Low 0-v/Off 0-v/Off VENTMIN L to VENTMAX ClosedOn Off Low 0-v/Off 0-v/Off VENTMIN L to Full-Open Closed to Full-OpenOn On High DELAY*24-v/On 0-v/Off† VENTMIN H to Full-Open Closed to Full-OpenENTHALPYCURVETEMP. DRYBULB (F)TEMP.DEWPOINT (F)ENTHALPY(btu/lb/da)POINT P1 POINT P2TEMP. (F) HUMIDITY(%RH) TEMP. (F) HUMIDITY(%RH)ES1 80 60 28.0 80 36.8 66.3 80.1ES2 75 57 26.0 75 39.6 63.3 80.0ES3 70 54 24.0 70 42.3 59.7 81.4ES4 65 51 22.0 65 44.8 55.7 84.2ES5 60 48 20.0 60 46.9 51.3 88.5HL 86 66 32.4 86 38.9 72.4 80.3