Carrier 39L specifications Variable Air Volume Units Only

Page 99

MIXED-AIR DAMPER CONTROL Ð The mixed-air damper control adjusts modulating outside-air, return-air, and exhaust- air dampers. When outside air conditions are unsuitable for atmospheric cooling, the dampers are held to an adjustable minimum outside air position. When outside air conditions are suitable for atmospheric cooling, the mixed-air dampers are modulated to maintain a space temperature that is be- tween the heating and cooling set points in an effort to mini- mize the need for heating or mechanical cooling. The damper set point is automatically adjusted as a function of outdoor- air temperature or can be set to a ®xed value by the user.

If the supply fan is OFF, the mixed-air dampers are kept closed to outside air and open to return air.

If the fan is ON, the system checks to see if the system is in the HEAT mode. If system is in the HEAT mode, the mixed- air dampers are held in the minimum position.

If the system is not in the HEAT mode, it determines if the outside conditions are suitable for atmospheric cooling. The control compares the outdoor-air temperature to the space temperature. If the outdoor-air temperature is less than the space temperature, the system does either an enthalpy check (using an outside-air enthalpy switch) or a differential en- thalpy check. (Return-air temperature is compared to return- air relative humidity for return-air differential enthalpy. Outside- air temperature is compared to outside-air relative humidity for outside-air differential enthalpy.)

The control then determines if the outdoor-air tempera- ture is below the Nighttime Free Cool Lockout (NTLO). If so, the damper set point is changed to 1.0 degree less than the Occupied Cooling set point, allowing the system to use return air during the heating mode.

If the outdoor-air temperature is higher than 68 F, the con- trol sets the damper set point to 1.0 degree higher than the Occupied Heating set point to provide cooling, allowing the system to use outside air.

If the outdoor-air temperature is higher than NTLO but less than 68 F, the system sets the damper set point halfway between the Occupied Heating and Occupied Cooling set points to provide ventilation.

If outside conditions are suitable, the control compares the space temperature to the damper set point and computes the supply-air temperature required to satisfy conditions.

Once the required supply-air temperature has been cal- culated, it is compared to the mixed-air temperature sensor value (if installed), otherwise the supply-air temperature sen- sor determines the damper position. The damper adjustment rate is limited to 5% per minute if the outside-air tempera- ture is less than 40 F. This rate limit prevents nuisance low temperature thermostat tripping.

ELECTRIC HEATER CONTROL Ð Electric heater stag- ing regulates the electric heater. The heater is staged to pre- vent the space temperature from falling below the desired set point. (The number of heat stages is factory set for each unit's heater.)

If the supply fan is OFF, all stages of electric heat are turned off.

If the fan is ON, the control reads the space temperature sensor and calculates the supply-air temperature required to satisfy conditions.

Once the required supply-air temperature has been cal- culated, it is compared to the actual supply-air temperature to determine the number of heat stages required to satisfy conditions. The required stages are energized one at a time, with 2-second intervals between stages.

ADAPTIVE OPTIMAL STOP ÐOptimal stop allows the space temperature to drift to an expanded occupied set point dur- ing the last portion of an occupied period. The control cal- culates a stop time offset, which is the time in minutes prior to the scheduled unoccupied time, during which expanded set points can be used. Adaptive optimal stop utilizes space temperature, an expanded Occupied set point, and a K factor to calculate stop time offset. The amount to expand the Oc- cupied set point is user con®gurable. Like adaptive optimal start, the control corrects itself for optimal operation by ad- justing the K factor.

TWO-STEP DEMAND LIMITING (Available on Units Connected to the Carrier Comfort Network Only) Ð If the Demand Limit option is enabled, the control receives and accepts redline alert and loadshed commands from the Network Loadshed option. See the CCN Loadshed manual for additional information.

When a redline alert is received, the Control decreases the Occupied Heating set point by 2° F and increases the Oc- cupied cooling set point by 2° F.

When a loadshed command is received, the supply fan turns OFF.

The maximum loadshed timer prevents the system from remaining in loadshed, should the control lose communica- tions with the Loadshed option. If the timer expires be- fore the loadshed command is cleared by the Loadshed op- tion, the control clears the loadshed command itself and returns to normal control. The loadshed timer is factory set at 60 minutes.

Variable Air Volume Units Only

CONSTANT OUTSIDE AIR (OAC) Ð During Occupied periods, this feature provides a continuous ¯ow of outside air into the building. The OAC control modulates the mixed- air damper to a con®gurable minimum open position to en- sure outside air is admitted. During Unoccupied periods, the control signals the dampers to fully close.

To monitor the outside air¯ow during Occupied periods, the OAC control reads the outside-air velocity pressure (OAVP) sensor, compares its value to the OAVP set point, and ad- justs the mixed-air dampers to the position required to achieve the con®gured velocity pressure.

If a control routine (other than OAC) or the con®gured minimum damper position require the dampers to be more fully open than the OAC setting, that routine or position over- rides the OAC control. To protect against coil freeze-up in colder climates, the PIC provides selectable low tempera- ture protection to limit the minimum mixed-air temperature to approximately 45 F.

See Fig. 79 for OAC control ¯owchart.

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Contents Contents Installation, Operation, Start-Up InstructionsSafety Considerations InstallationGeneral Page VAV ABXIGV PICNormally Closed Direct ExpansionFMB Ð Filter Mixing Box MXB Ð Mixing BoxControl Box for Remote Mounting AQ2 AFSAotc AQ1PIC Section Control Box Component Arrangements, 39L PIC Section Control Box Component Arrangement, 39NX Sizes PIC Section Control Box Component Arrangement, 39NX Sizes Page Address Input and Output PointsUnit Wiring Schematic, 39L Sizes 03-35 115 v, Typical Unit Wiring Schematic, 39L Sizes 03-35 115 v, Typical Unit Wiring Schematic, 39L Sizes 03-35 115 v, Typical Unit Wiring Schematic, 39L Sizes 03-35 115 v, Typical Unit Wiring Schematic, 39L Sizes 03-35 115 v, Typical Unit Wiring Schematic, 39L Sizes 03-35 115 v, Typical Unit Wiring Schematic, 39NX Sizes 07-21 115 v, Typical Unit Wiring Schematic, 39NX Sizes 07-21 115 v, Typical Unit Wiring Schematic, 39NX Sizes 07-21 115 v, Typical Unit Wiring Schematic, 39NX Sizes 07-21 115 v, Typical Unit Wiring Schematic, 39NX Sizes 07-21 115 v, Typical Unit Wiring Schematic, 39NX Sizes 07-21 115 v, Typical Unit Wiring Schematic, 39NX Sizes 26-92 115 v, Typical Unit Wiring Schematic, 39NX Sizes 26-92 115 v, Typical Unit Wiring Schematic, 39NX Sizes 26-92 115 v, Typical Unit Wiring Schematic, 39NX Sizes 26-92 115 v, Typical Unit Wiring Schematic, 39NX Sizes 26-92 115 v, Typical Unit Wiring Schematic, 39NX Sizes 26-92 115 v, Typical Page Page Page Page Page Page Terminal Signal Junction Box Connections for Optional Remote Control BoxValve Assembly Typical Hot Water Valve Wiring Duct Static Pressure Probe Chilled Water Valve WiringNema Ð National Electrical Manufacturers Association Ohms Resistance TemperatureMixed-Air Temperature Sensor HH79NZ021 Installation Supply/Return Air Temperature Sensor HH79NZ019 Enthalpy Control SettingsCOI L Comno Wall-Mounted Relative Humidity Sensor Fig Duct-Mounted Relative Humidity Sensor Locations Air¯ow Switch P/N HK06WC030 CGCDXGAS001A00 CO2 Sensor AccessoriesCGCDXSEN002A00 CGCDXSEN003A00CO2 Concentration PPM Air Quality CO2 Sensor Wall Mount Version ShownOAC Pressure Transducers Sensor Module PIN no Recommended Sensor Device WiringManufacturer Part Number ProcessorField Wiring of Sensors Stroke Recommended ActuatorsField-Supplied Mixing Box Actuator Signal Wiring Fire Shut Down Terminal Block HAND/OFF/AUTO Switch Tran Ð TransformerHigh-Pressure Switch Remove Jumper Evacuation Supply Fan ContactorPres Single-Pole, Double-Throw Spdt Relay Wiring of Device Under Discrete Output Temperature Control Wiring of Two-Stage Humidication Control Relays Duct Mounted Relative Humidity Transmitter Wiring Air Quality and Oavp Sensor Wiring Wiring of Return Fan Volume Control With IGVs Control System Pulse-Type Meter WiringCCN Communication Wiring Outdoor Air Thermostat AHUAir Handling Unit Relay ModuleLocal Interface Device Key Usage Function USE KeysOperative USE Keys Oavp Status History Schedule Service Set Point TestFunctions and Subfunctions SUB Function NumberOperation Keyboard Display Description Entry Control OperationStatus Keyboard DirectoryInputs VAV Direct Expansion Oavp Ð Outside Air Velocity Pressure AIRQUAL1 SET Point Quick Test History Example 1 Ð Reading Alarm Codes Example 2 Ð Reading Current Operating ModesKeyboard Display Comments Entry Response Display Description AlarmsDisplay Codes Force StatesRelay Stages State of Items ControlledExample 3 Ð Forcing An Input Value Example 4 Ð Forcing An Output ValueTo LOG OFF Example 5 Ð Using Quick TestExample 6 Ð Logging On and Logging Off Service Function Keyboard Display Comments Entry Response To LOG onService Conguration Ranges and Defaults Analog Output Temperature Control Example 7 Ð Reading and Changing Factory Congurations Example 8 Ð Conguration of MeasurementsExample 9 Ð User Congurations Example 11 Ð Conguration of Space Temperature Reset Example 10 Ð Conguration of Heating CoilExample 12 Ð Conguration of Loadshed Example 14 Ð Conguration of Alarm Limits Example 15 Ð Conguration of Analog Temperature ControlExample 13 Ð Conguration of Fan Tracking Set Point Ranges and Defaults Example 16 Ð Conguration of Discrete Temperature ControlExample 17 Ð Service History Conguration Example 18 Ð Service/Maintenance Alarm CongurationExample 21 Ð Setting of Time and Date Example 22 Ð Setting Daylight Savings TimeExample 20 Ð Reading and Changing System Set Points Schedule I Sample Time Schedule Example 23 Ð Setting of HolidaysExample 24 Ð Using the Schedule Function Keyboard Display Comment Entry Response Programming PeriodPeriod 1 Dene schedule period For this example, Period 6 is used for holiday only Control Operating Sequence Constant Volume and Variable Air Volume UnitsPage Page Indoor-Air Quality MAT Ð Mixed-Air TemperatureOAT Ð Outdoor-Air Temperature IAQConstant Volume Units Only RAT Ð Return-Air CCV Ð Cooling Coil ValveDX Submaster Gain Control Operation Variable Air Volume Units Only Page Oavp Ð Outside Air Velocity Pressure Outside AirOAC Constant Outside Air102 Initial Check START-UPKeyboard Display COMMENTS/ACTION Entry Response Test of Input SignalsFollowing Keyboard Display COMMENTS/ACTION Entry Response FSD NRMFor Variable Air Volume Units Test of Output SignalsElectric Heater Test Test of Output Options Using Option ModuleDC Milliamps DC Voltage Control Loop CheckoutDirect Expansion DX Cooling Test Digital DC Volt Meter vs DC Milliamp MeterRecommended Gain Starting Valves Valve TroubleshootingHCV 10/FORCED Typical LinkagesExample 25 Ð Forcing An Output IGV %Control Module Troubleshooting Example 26 Ð Heating Coil Valve Test Way Normally OpenExit Test Dsio Problem Possible Cause Corrective Action Unit TroubleshootingHCV, CCV, IGV IAQ features OAC malfunctioningMalfunctioning Metric Conversion Chart

39L specifications

The Carrier 39L is a cutting-edge air conditioning unit designed for both residential and commercial applications, providing exceptional cooling and heating performance. Equipped with advanced technologies, this system ensures optimal climate control while maintaining energy efficiency.

One of the standout features of the Carrier 39L is its inverter technology. This innovation allows the system to adjust its compressor speed based on the ambient temperature, which results in a significant reduction in energy consumption. By operating at varying capacities rather than a fixed output, the 39L can maintain a consistent temperature, enhancing comfort while lowering electricity bills.

The Carrier 39L also includes a high-efficiency air filtration system, designed to capture dust, allergens, and other airborne particles. This not only improves indoor air quality but also promotes a healthier living environment. The filtration system is complemented by anti-bacterial treatment, ensuring that the air circulated within your space is both clean and refreshing.

In terms of design, the Carrier 39L boasts a sleek and compact form factor, making it easy to integrate into various settings, from homes to offices. Its quiet operation is another notable feature, as it minimizes noise levels, allowing occupants to enjoy a serene atmosphere without disruptive sound.

Further enhancing convenience, the Carrier 39L comes equipped with smart connectivity options. Users can control the unit remotely via a smartphone app, making it easy to adjust settings, program schedules, and monitor energy usage from anywhere. This feature not only improves user experience but also supports energy-saving practices.

Durability is also a key characteristic of the Carrier 39L. Constructed with high-quality materials and coated with corrosion-resistant treatments, the unit is built to withstand various environmental conditions. This ensures long-lasting performance and reduces the need for frequent maintenance.

Overall, the Carrier 39L is a versatile, efficient, and user-friendly air conditioning solution. Its blend of advanced technologies, energy-saving capabilities, and robust design makes it an ideal choice for those seeking reliable climate control in their spaces. Whether for residential comfort or commercial necessity, the Carrier 39L stands out as a leader in modern air conditioning.
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