analog to digital converter . . . . . . . . . . . . . . . 4 - UPGNet

351579-YTS-B-0608Table 12: Holiday ScheduleHoliday Number Start MonthStart Dayof MonthStart TimeNumberof DaysHoliday 1 00 00 00:00 00Holiday 2 00 00 00:00 00Holiday 3 00 00 00:00 00Holiday 4 00 00 00:00 00Holiday 5 00 00 00:00 00Holiday 6 00 00 00:00 00Holiday 7 00 00 00:00 00Holiday 8 00 00 00:00 00Holiday 9 00 00 00:00 00Holiday 10 00 00 00:00 00Holiday 11 00 00 00:00 00Holiday 12 00 00 00:00 00Holiday 13 00 00 00:00 00Holiday 14 00 00 00:00 00Holiday 15 00 00 00:00 00Holiday 16 00 00 00:00 00Holiday 17 00 00 00:00 00Holiday 18 00 00 00:00 00Holiday 19 00 00 00:00 00Holiday 20 00 00 00:00 00Full heating (all stages) is ON when RAT drops 2 °F below thesetpoint, heating is OFF when RAT is at, or above the setpoint.(Note that in this case, the control will use all available heatingstages, regardless of setting of the programmable parameter"Heat Stages"). Before energizing heat for Morning Warm Upthe control will start the Fan and operate it for 5 minutes. TheEconomizer will stay closed and the Fan will continue to runduring the Morning Warm Up. The Morning Warm Up willterminate when the Occupied period begins.If the RAT setpoint is achieved before the MWU period expires,Unoccupied cooling is permitted. If further heating is neededduring the Occupied period, it is controlled by a VAV OccupiedHeating algorithm (if enabled and if a Space Sensor is used), orby a space thermostat.The same algorithm is also used for VAV Occupied Heating(see also paragraph "VAV Occupied heating" in "OptionOperation" section earlier in this document). In this case, theVAV Occupied Heating control algorithm is activated under thecontrol of the Space Sensor (whenever the zone temperaturesensed by the Space Sensor drops 2 °F or more below aprogrammed "VAV SAT Reset Setpoint"). Once activated, theOccupied Heating control algorithm controls RAT between theMWU RAT Setpoint and two degrees below the setpoint andcycles the fan the same way as the MWU algorithm.The specified Max Morning Warm Up Time is not used to limitthe duration of VAV Occupied Heating. During heating forMorning Warm Up, or for VAV Occupied heating function, theVAV boxes controls will receive an override signal to open theVAV box damper. This is accomplished by wiring the VAV heatrelay for the VAV boxes to open, and energizing it from Heatoutput of the controller. Note that as the first stage of heatcycles on / off, the VAV box heat relay will cycle with it.UNOCCUPIED VAV HEATING / COOLING CONTROLALGORITHM WITH A SPACE SENSORIn the unoccupied mode, the Space Sensor will compare thetemperature in a selected VAV zone to the programmedUnoccupied Heating and Cooling setpoints and request heatingor cooling using the following control algorithm:OCCUPIED VAV HEATING / COOLING CONTROLALGORITHM WITH A SPACE SENSORIn the occupied mode, the control will compare the temperaturein a selected VAV zone to the programmed "VAV SAT ResetSetpoint" and request heating or cooling using the followingcontrol algorithm: The transition from cooling to occupiedheating occurs at 2 °F below the "VAV SAT Reset Setpoint".There is no "satisfied", or "idle" state of the unit between coolingand occupied heating.The above algorithm only requests occupied cooling andselects a SAT occupied cooling setpoint, or requests occupiedheating at a programmed "Morning Warm Up RAT Setpoint".Once requested by this Space Sensor algorithm, the cooling iscontrolled by the SAT control algorithm described in paragraph"SAT Control Algorithm in VAV Cooling" earlier in this section[not to be found by that name...]. Once requested by this SpaceSensor algorithm, the occupied heating is controlled by the RATcontrol algorithm described in paragraph "Morning Warm Up /VAV Occupied Heating Control Algorithm" earlier in this section.CONTROLLING EXCESSIVE SAT (SUPPLY AIRTEMPERATURE)This is required in cooling operation in order to prevent adanger of "slugging" and damage to the DX compressors.Rooftop units do not use accumulators on compressor intake,and liquid refrigerant could enter the intake of a compressor incase of a low heat transfer on the evaporator coil. In heatingoperation, the Excessive SAT control is not used.SAT CONTROL CONFIGURATIONSAT control for cooling is configurable to enable or disable(on/off). The default setting for cooling is ON. The user is notnormally expected to turn this mode OFF, but the possibility ofturning it OFF is provided mainly for troubleshooting purposes.Johnson Controls Unitary Products 35