American Standard UV05 manual Night Purge Mode State, Fan Only Mode State a

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Description of Operation

Night Purge Mode (State 8)

Night Purge mode is provided as a means to more easily and quickly ventilate a space. Night purge can be useful in helping to remove odor build up at the end of each day, or after cleaning, painting, or other odor generating operations occur within the space. Night Purge mode consists of a single UVC state: Night Purge [8].

Night Purge is a full ventilation with exhaust mode, during which room comfort is likely to be compromised. Therefore, McQuay strongly recommends using Night Purge only when the space is unoccupied.

When Night Purge mode becomes active, the UVC stops all normal heating and cooling. Since any new energy used to treat the incoming air would be wasted in the purge process. In the Night Purge mode, the space fan is set to high speed, the OA damper is set to 100% open, and the Exhaust Fan binary output (see “External Binary Outputs” on page 38) is set to ON. If the UVC is not set to another mode within 1 hour (fixed), the UVC automatically switches to the Fan Only mode (see “Fan Only Mode (State A)” on page 15).

While in Purge mode, the UVC does not maintain DA temperatures. If the space temperature drops below the EHS, the UVC is forced into the Emergency Heat mode (see “Emergency Heat Mode (Super State)” on page 16).

Figure 8: Night purge state diagram

Night Purge

8

UVC Mode ≠

Night purge

UVC Mode =

Night purge

Transition point

Fan Only Mode (State A)

The Fan Only mode is provided so that the UVC can be forced into a Fan Only operation via a keypad/display or a network connection. Fan Only mode consists of a single UVC state: Fan Only [A].

When Fan Only mode becomes active, the UVC stops all normal heating and cooling.

While in Fan Only mode, the UVC does not maintain DA temperatures. If the space temperature drops below the EHS, the UVC is forced into the Emergency Heat mode (see “Emergency Heat Mode (Super State)”).

Figure 9: Fan only state diagram

UVC Mode ≠

Fan Only

		UVC Mode	=	Fan Only
	Transition	UVC Mode	=	A
	Transition	Fan Only		A
	point

McQuay OM 751

15

Image 15

Contents DX Cooling Only Software Model UV05 Group Applied SystemsDate November Description of Operation UVC Configuration ParametersIntroduction Getting StartedModel-specific unit ventilator installation literature Accessory-specific installation literatureDescription Manual # Software program literature Extreme temperature can damage system componentsAcronyms/Abbreviations Acronyms and abbreviationsDescription Acronym Abr OCS Security Levels Using the Keypad/DisplayDisplay Format Keypad FunctionsArrow Keys Mode KeyON/STOP Key and LED FAN KeyChanging Set Points Using the Keypad/DisplayViewing Actual Indoor Air Temperature IAT Menu ReferenceRW1 Abr Description DefaultChlo State Programming Description of OperationUVC Unit Modes Complete UVC-state diagramDecimal OFF Mode StateUVC state names and numbers Normal UVC modes State namesFan Only Mode State a Night Purge Mode StateEmergency Heat Mode Super State Full Heat State StateCant Heat State State D Auto Mode Heat Mode Super StateHeat State State Cool Mode Super State Low Limit State State ECant Heat State State B Econ State State Cool mode super state diagramMech State State Econ Mech State StateCant Cool State State C Special Purpose Unit ModesDischarge Air DA Heat State State Low Limit State State FShutdown Mode Pressurize ModeDepressurize Mode Purge ModePriority result Unit Mode PrioritySpecial purpose UVC unit mode priority Normal UVC mode priorityOccupancy mode priority Occupied ModeUnoccupied Mode Standby ModeAdditional Occupancy Features Networked Set Point Offset Capability Space Temperature Set PointsNetworked Space Temperature Sensor Capability Networked Set Point CapabilityEffective Set Point Calculations Remote Wall-Mounted Sensor with +/-3F Adjustment optionalSet point calculation examples Example a Example B GivenEffective set point calculations PI loops Discharge Air Temperature ControlProportional Integral PI Control Loops PI loop listProportional Band PI Control ParametersIndoor Air Fan Operation Integral TimeOccupied, Standby, and Bypass Operation Outdoor Air Damper Operation Economizer enable EconomizerOA temp sensor Space humidity Networked Space CO2 Sensor Capability Networked Space Humidity Sensor CapabilityNetworked Outdoor Humidity Sensor Capability CO2 Demand Controlled Ventilation optionalCompressor Cooling Lockout Compressor OperationAshrae Cycle Compressor EnvelopeOutdoor Air Fan Operation Compressor Minimum On and Off TimersCompressor Start Delay Floating-Point Actuator Auto-Zero, Overdrive and SyncExternal Binary Inputs Unoccupied Input SignalRemote Shutdown Input Signal Ventilation Lockout Input SignalExternal Binary Outputs Exhaust Interlock Input SignalLights On/Off Signal Fault SignalStart/Stop Calculation Exhaust Fan ON/OFF SignalAuxiliary Heat Signal Auxiliary heat start/stop calculationExpansion board Inputs and outputs, software model 05-DX cooling onlyAlarm and Fault Monitoring Alarm and fault code summaryPriority Fault description Reset Keypad Discharge Air DX Cooling Low Limit Indication F3 DX Pressure Fault F1Compressor Envelope Fault F2 Space Temp Sensor Failure F0Discharge Air Temp Sensor Failure F7 Condensate Overflow Indication optional F4Space Coil DX Temp Sensor Failure F5 Outdoor Temp Sensor Failure F6Troubleshooting Temperature Sensors Temperature versus resistance Troubleshooting Humidity SensorsRH % VDC mV Troubleshooting Carbon Dioxide CO2 SensorsHumidity versus voltage CO2 versus voltage tableConfiguration Parameter Name Abr Default LUI Menu UVC configuration parameters OMAbr Default LUI Menu OAD Stroke Time Warranty