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

351579-YTS-B-0608UNOCCUPIED HEATING WITH A THERMOSTATThis operation is identical to the Occupied heating, except theunit mode is in Unoccupied mode from the internal controlOccupied/Unoccupied table. The economizer damper remainsfully closed in the unoccupied mode.OCCUPIED COOLING WITH A THERMOSTATIn this mode, the control uses a thermostat for cooling and fanoperation. The thermostat's occupied cooling setpoint shouldbe set below the zone thermostat's lowest adjustable coolingsetpoint, to prevent a possibility of cooling turned off while otherzone(s) in the system still have a cooling demand.UNOCCUPIED COOLING WITH A THERMOSTATThis operation is identical to the Occupied cooling, except whenoperating in the unoccupied mode the control is programmed tocontrol to its unoccupied cooling setpoint and the economizerdamper min. position is set to 0%, however the damper maymodulate open if outdoor air can be used for free cooling(economizer operation).OCCUPIED HEATING WITH A SPACE SENSORThe Space Sensor is placed in a selected, representative zoneof the VAV system, in addition to the zone thermostat, or sensorused to control the zone's VAV box. The heating controlalgorithm is enabled whenever the zone temperature drops 2 °For more below a programmed "VAV SAT Reset Setpoint", anddisabled whenever the zone temperature is 1.5 °F, or lessbelow a programmed “VAV SAT Reset Setpoint". The "VAV SATReset Setpoint" would typically be set at, or below the lowestzone temperature setpoint selectable on the zone thermostat.The supply fan is controlled to 100% during occupied heatingand cycles OFF when the heating control algorithm is satisfied ifthere is no other call for the fan. On startup, the fan speed isramped up, or the inlet vanes ramped open (a "soft start").When a call for heating (W1 or W2=ON) occurs, the economizerdamper remains at its programmed minimum position and allVAV boxes go fully open - box heat relays are energized fromHeat output of the controller.If Hydronic heat option is used, the Heat output of the controlleris also actuated during heating and the SAT is controlled to the2nd stage hydronic heat setpoint.UNOCCUPIED HEATING WITH A SPACE SENSORWhen this mode is enabled and the unit enters the unoccupiedmode, the unit will control heating by comparing the zonetemperature to a programmed "Unoccupied Heating Setpoint".The Space Sensor should be placed in a selected,representative zone of the VAV system, in addition to the zonethermostat, or sensor used to control the zone's VAV box.Full heating (all heating stages ON) occurs when the SpaceSensor algorithm requests heating, no heating (all heatingstages OFF) when the Space Sensor algorithm is satisfied (notethat in this case, the control will use all available heating stages,regardless of setting of the programmable parameter "HeatStages").The supply fan is controlled to 100% during unoccupied heatingand cycles OFF when the Space Sensor control algorithm issatisfied if there is no other call for the fan. On startup, the fanspeed is ramped up, or the inlet vanes ramped open (a "soft start").During unoccupied heating, the economizer damper is fullyclosed and all VAV boxes go fully open - box heat relays areenergized from Heat output of the controller.OCCUPIED COOLING WITH A SPACE SENSORThis mode is entered when the control sees a Space Sensorsignal and enters the "occupied" mode. The Space Sensorrequests cooling (to a programmed High, or Low SAT setpoint)whenever the zone temperature increases by a specifiedamount above a programmed "VAV SAT Rest Setpoint". TheSpace Sensor should be placed in a selected, representativezone of the VAV system, in addition to the zone thermostat, orsensor used to control the zone's VAV box.The "VAV SAT Reset Setpoint" would typically be set at, orbelow the lowest zone temperature setpoint selectable on thezone thermostat, in order to prevent a possibility of insufficientcooling while other zone(s) in the system still have a highcooling demand.The supply fan, economizer, VAV boxes operate within theirnormal control rules.UNOCCUPIED COOLING WITH A SPACE SENSORIn this mode, the Space Sensor requests cooling based oncomparing the zone temperature to a programmed"Unoccupied Cooling Setpoint". When the Space Sensor controlalgorithm requests cooling, the unit runs cooling controlled to aprogrammed High SAT setpoint ("VAV Upper Cooling SATSetpoint"), or to a programmed Low SAT Setpoint ("VAV UpperCooling SAT Setpoint"), as determined by comparison of zonetemperature to a programmed "VAV SAT Reset Setpoint". The"VAV SAT Reset Setpoint" would typically be set well below the"Unoccupied Cooling Setpoint", causing the unoccupied coolingto typically use a Low SAT Setpoint.There are two different SAT control algorithms, one used whenfree cooling is available (economizer operation) and the otherone for mechanical cooling only. These two SAT controlalgorithms are described in the “Occupied Cooling inStandalone Operation” section below. Since the economizer isnot active in Unoccupied mode, this will be restricted tomechanical cooling.UNOCCUPIED HEATING IN STANDALONE OPERATIONUnoccupied heating is never used in standalone operation.OCCUPIED COOLING IN STANDALONE OPERATIONThe unit controls cooling to a programmed Low SAT setpoint("VAV Lower Cooling SAT Setpoint") during the occupied mode.There are two different SAT control algorithms, one used whenJohnson Controls Unitary Products 33