Manuals / American Standard / Household Appliance / Air Conditioner

American Standard UV05 manual Troubleshooting Carbon Dioxide CO2 Sensors, Humidity versus voltage

Models: UV05

1 50

Download 50 pages 38.18 Kb

Page 46

Diagnostics and Service

Table 24: Humidity versus voltage.

RH (%)	VDC (mV)	RH (%)	VDC (mV)
10	1330	55	2480
15	1475	60	2600
20	1610	65	2730
25	1740	70	2860
30	1870	75	2980
35	1995	80	3115
40	2120	85	3250
45	2235	90	3390
50	2360	95	3530

Troubleshooting Carbon Dioxide (CO2) Sensors

The UVC is configured to use a 0–2000 PPM, 0–10 VDC, single beam absorption infrared gas sensor. Each sensor is calibrated according to the table shown.

Use the following procedure to troubleshoot a suspect sensor.

1Disconnect the sensors output voltage lead from the UVC analog input (xAI-3).

2Using some other calibrated CO2 sensing device, take a CO2 reading at the sensor location.

3Use the CO2 reading from Step 2 to determine the expected sensor voltage from Table 25.

4Using a calibrated multi-meter, measure the actual voltage across the lead removed from xAI-3 and ground.

5Compare the expected voltage to the actual voltage.

6If the actual voltage value deviates substantially (more than 10%) from the expected voltage, replace the sensor.

In the unlikely event that the CO2 sensor requires calibration, consult the factory for information on obtaining calibration equipment and instructions.

Table 25: CO2 versus voltage table

CO2 (PPM)	VDC (V)	CO2 (PPM)	VDC (V)
300	1.5	1200	6.0
400	2.0	1300	6.5
500	2.5	1400	7.0
600	3.0	1500	7.5
700	3.5	1600	8.0
800	4.0	1700	8.5
900	4.5	1800	9.0
1000	5.0	1900	9.5

46	McQuay OM 751

Image 46

American Standard UV05 manual Troubleshooting Carbon Dioxide CO2 Sensors, Humidity versus voltage, CO2 versus voltage table

Contents

Model AHV - Ceiling Mounted DX Cooling Only Software Model UV05Model AVV - Floor Mounted Operation Maintenance ManualRemote Wall-MountedSensor with +/-3F Introduction IntroductionIntroduction Extreme temperature can damage system componentsIntroduction Acronyms/AbbreviationsTable 5 Acronyms and abbreviations Introduction McQuay OMDisplay Format Using the Keypad/DisplayGetting Started Keypad FunctionsMODE Key ON/STOP Key and LEDFAN Key Arrow KeysMenu Reference Using the Keypad/Display70 FUNC Getting Started Page Description of Operation State ProgrammingUVC Unit Modes Figure 6 Complete UVC-statediagramFigure 7 Off state diagram OFF Mode StateTable 8 UVC state names and numbers Night 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 Figure 12 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 ModeTable 10 Special purpose UVC unit mode priority Unit Mode PriorityTable 11 Normal UVC mode priority Unoccupied Mode Occupancy ModesOccupied Mode Standby ModeRemote Wall-MountedSensor Tenant Override Switch Additional Occupancy FeaturesUnit-MountedTenant Override Switch Bypass ModeNetworked Set Point Offset Capability Space Temperature Set PointsNetworked Set Point Capability Networked Set Point Shift CapabilityRemote Wall-MountedSensor with 55F to 85F Adjustment optionalRemote Wall-MountedSensor with +/-3F Effective Set Point CalculationsTable 15 Set point calculation examples Description of OperationFigure 16 Effective set point calculations Example A Example BProportional Integral PI Control Loops Discharge Air Temperature ControlPI Control Parameters Proportional BandArea Under The Curve Indoor Air Fan OperationIntegral Time Too SmallCycle Fan Outdoor Air Damper OperationUnoccupied Operation Off DelayEconomizer Economizer enableMcQuay OM EconomizerCO2 Demand Controlled Ventilation optional Networked Space Humidity Sensor CapabilityNetworked Outdoor Humidity Sensor Capability Networked Space CO2 Sensor CapabilityCompressor Envelope Compressor OperationASHRAE Cycle Compressor Cooling LockoutOutdoor Air Fan Operation Compressor Minimum On and Off TimersCompressor Start Delay McQuay OMInput 3 Ventilation lockout default or 3 sets of dry contacts to signal UVCInput 1 Unoccupied default External Binary InputsOutput 2 Fault signal 3 relay type outputs w/signal voltageOutput 1 Relay output for light signal Output 3 Exhaust fan operation default orAuxiliary Heat Signal Exhaust Fan ON/OFF SignalTable 20 Auxiliary heat start/stop calculation UVC Input and Output Table UVC Input and Output TableDiagnostics and Service Alarm and Fault MonitoringSpace 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 EPROM Memory Indicator EEConfiguration Display Space Humidity Sensor Failure optional FATroubleshooting Humidity Sensors Table 23 Temperature versus resistanceTable 24 Humidity versus voltage Troubleshooting Carbon Dioxide CO2 SensorsTable 25 CO2 versus voltage table UVC Configuration Parameters UVC Configuration Parameters UVC Configuration Parameters McQuay OMWarranty McQuay Training and Development