York ECO R-407C User Manual

YORK INTERNATIONAL30Stand Alone ControlIf the unit is not configured for Thermostat or Zone Sen-sor operation, the unit will operate in Stand Alone Mode.In Stand Alone Mode, the OptiLogic™ Controller willmonitor only the Occupied/Unoccupied state. When theunit is commanded into the Occupied Mode of opera-tion, the OptiLogic™ Controller will start the Supply Fan.If the unit is equipped with an Economizer, the Control-ler will check to see if Outside Air conditions are suit-able for Economizing. The controller will then use Out-side Air (when available and suitable) and/or stage com-pressors up and down, as required, to maintain the VAVLow SAT Setpoint.CV SPECIFIC SEQUENCESCooling OperationThermostat ControlIf a 7-wire thermostat (2 Cool/2Heat) controls the unit,all zone temperature setpoint control is maintained atthe thermostat. With this operation, the unit remainsidle until it receives a stage call from the Thermostat. If“G” is called from the thermostat, the Supply Fan willstart and all occupied functions (if equipped), i.e. venti-lation, economizer, etc. will be allowed to operate.Stage 1 (“Y1”) CallIf Y1 is called and the unit is equipped with an econo-mizer, the control will check to see if the Outside Air issuitable for economizing. If conditions are suitable foreconomizing, the control will control the economizer andstage up compressors, as required, to maintain a highSAT setpoint. If conditions are not suitable for econo-mizing or not equipped with an economizer, the controlwill stage up 50% of the compressors. This shall bemaintained until Stage 1 is deactivated or Stage 2 iscalled.Stage 2 (“Y2”) CallIf Y2 is called and the unit is equipped with an econo-mizer, the control will check to see if the Outside Air issuitable for economizing. If conditions are suitable foreconomizing, the control will control the economizer andstage up compressors, as required, to maintain a LOWSAT setpoint. If conditions are not suitable for econo-mizing or not equipped with an economizer, the controlwill stage up 100% of the compressors. This shall bemaintained until Stage 2 is deactivated.Zone Sensor ControlIf a zone sensor controls the unit, the OptiLogic™ con-troller shall maintain all zone temperature setpoints.These setpoints are user selectable at the OptiLogic™User Interface.When a zone sensor is used for control, the OptiLogic™unit controller will monitor the temperature within thespace and control the unit accordingly. A closed-loopstaging algorithm is used to stage compressors up anddown as required to maintain the desired zone tempera-ture setpoint. If the unit is equipped with an economizer,Outside Air conditions are continuously monitored by thecontrol to determine if conditions are suitable for econo-mizing. If conditions are suitable for economizing, theOptiLogic™ controller will modulate the Outside Airdamper in addition to staging compressors up and downto maintain the zone temperature setpoint.Controls (continued)