American Standard UV05 manual Networked Space Humidity Sensor Capability

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Description of Operation

Networked Space Humidity Sensor Capability

A networked space humidity sensor can be network interfaced with the Space Humidity Input variable. When the Space Humidity Input variable is used (valid value), it automatically overrides the hard-wired space humidity sensor (if present).

Networked Outdoor Humidity Sensor Capability

A networked outdoor humidity sensor can be network interfaced with the Outdoor Humidity Input variable. When the Outdoor Humidity Input variable is used (valid value), it automatically overrides the hard-wired outdoor humidity sensor (if present).

CO2 Demand Controlled Ventilation (optional)

Ventilation equipment typically uses fixed damper positions to determine the amount of OA for proper ventilation within the space. Most commonly, the fixed position of the OA damper is based on the maximum number of occupants the space is designed to accommodate. However, this fixed OA damper operation ignores the fact that most spaces during the day have varying occupancy levels and may only rarely reach maximum design occupancy levels. This type of fixed damper control for ventilation is energy wasteful since you are treating OA not actually needed for ventilation during low occupancy levels.

People produce CO2 when they breath; the CO2 level within the space has a direct relationship with the number of people within that space.

The UVC can optionally be factory configured to provide CO2-based Demand Controlled Ventilation (DCV). The CO2 DCV function is useful in saving the energy typically wasted in treating OA not actually needed for ventilation within a space during occupancy levels below maximum design. The CO2 DCV function uses a PI-loop control to adjust the OA damper above the minimum position as needed to maintain the Space CO2 Setpoint (1200 PPM default).

The minimum damper position used with CO2 DCV typically can be set at ~20% of the minimum position that would be used without CO2 DCV. For example, if the minimum OA damper position typically is 20% then when using CO2 DCV, you could set the new minimum OA damper position as low as 4% (e.g., 20% × 0.20 = 4%). This new, smaller minimum OA damper position then should provide enough ventilation to keep odors in check within the space for most applications.

Note – The CO2 DCV function can increase the OA damper position past that required by the economizer and vice versa.

–If odors within the space become a problem, increase the OA damper minimum position as needed to eliminate these odors. It may be necessary with new construction or after renovation to raise the minimum position for some time period to help reduce odor build- up due to the out-gassing of new construction material and then return the minimum OA damper position at a later date.

–If the CO2 Demand Controlled Ventilation (DCV) option is used, the UVC only uses the IA fan high speed OA damper minimum position regardless of fan speed. The DCV function adjusts the OA damper above this minimum as needed. In this case, the IA fan high speed OA damper minimum position is factory set at 5%.

Networked Space CO2 Sensor Capability

A networked space CO2 sensor can be network interfaced with the Space CO2 Input variable. When the Space CO2 Input variable is used (valid value), it automatically overrides the hard- wired space CO2 sensor (if present).

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McQuay OM 751

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Contents Group Applied Systems DX Cooling Only Software Model UV05Date November Getting Started UVC Configuration ParametersIntroduction Description of OperationAccessory-specific installation literature Model-specific unit ventilator installation literatureDescription Manual # Extreme temperature can damage system components Software program literatureAcronyms and abbreviations Acronyms/AbbreviationsDescription Acronym Abr OCS Keypad Functions Using the Keypad/DisplayDisplay Format Security LevelsFAN Key Mode KeyON/STOP Key and LED Arrow KeysMenu Reference Using the Keypad/DisplayViewing Actual Indoor Air Temperature IAT Changing Set PointsAbr Description Default RW1Chlo Description of Operation State ProgrammingComplete UVC-state diagram UVC Unit ModesNormal UVC modes State names OFF Mode StateUVC state names and numbers DecimalNight Purge Mode State Fan Only Mode State aFull Heat State State Emergency Heat Mode Super StateCant Heat State State D Heat Mode Super State Auto ModeHeat State State Low Limit State State E Cool Mode Super StateCant Heat State State B Cool mode super state diagram Econ State StateEcon Mech State State Mech State StateLow Limit State State F Special Purpose Unit ModesDischarge Air DA Heat State State Cant Cool State State CPurge Mode Pressurize ModeDepressurize Mode Shutdown ModeNormal UVC mode priority Unit Mode PrioritySpecial purpose UVC unit mode priority Priority resultStandby Mode Occupied ModeUnoccupied Mode Occupancy mode priorityAdditional Occupancy Features Networked Set Point Capability Space Temperature Set PointsNetworked Space Temperature Sensor Capability Networked Set Point Offset CapabilityRemote Wall-Mounted Sensor with +/-3F Adjustment optional Effective Set Point CalculationsExample a Example B Given Set point calculation examplesEffective set point calculations PI loop list Discharge Air Temperature ControlProportional Integral PI Control Loops PI loopsPI Control Parameters Proportional BandIntegral Time Indoor Air Fan OperationOccupied, Standby, and Bypass Operation Outdoor Air Damper Operation Economizer Economizer enableOA temp sensor Space humidity CO2 Demand Controlled Ventilation optional Networked Space Humidity Sensor CapabilityNetworked Outdoor Humidity Sensor Capability Networked Space CO2 Sensor CapabilityCompressor Envelope Compressor OperationAshrae Cycle Compressor Cooling LockoutFloating-Point Actuator Auto-Zero, Overdrive and Sync Compressor Minimum On and Off TimersCompressor Start Delay Outdoor Air Fan OperationVentilation Lockout Input Signal Unoccupied Input SignalRemote Shutdown Input Signal External Binary InputsFault Signal Exhaust Interlock Input SignalLights On/Off Signal External Binary OutputsAuxiliary heat start/stop calculation Exhaust Fan ON/OFF SignalAuxiliary Heat Signal Start/Stop CalculationInputs and outputs, software model 05-DX cooling only Expansion boardAlarm and fault code summary Alarm and Fault MonitoringPriority Fault description Reset Keypad Space Temp Sensor Failure F0 DX Pressure Fault F1Compressor Envelope Fault F2 Discharge Air DX Cooling Low Limit Indication F3Outdoor Temp Sensor Failure F6 Condensate Overflow Indication optional F4Space Coil DX Temp Sensor Failure F5 Discharge Air Temp Sensor Failure F7Troubleshooting Temperature Sensors Troubleshooting Humidity Sensors Temperature versus resistanceCO2 versus voltage table Troubleshooting Carbon Dioxide CO2 SensorsHumidity versus voltage RH % VDC mVUVC configuration parameters OM Configuration Parameter Name Abr Default LUI MenuAbr Default LUI Menu OAD Stroke Time Warranty
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