Carrier 39L Control Operating Sequence, Constant Volume and Variable Air Volume Units

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CONTROL OPERATING SEQUENCE

Constant Volume and Variable Air Volume Units

TWO-POSITION DAMPER CONTROL Ð Two-position damper control opens or closes ®eld-supplied and installed two-position outdoor-air dampers in order to provide mini- mum outdoor air ventilation.

If the supply fan is OFF, the damper is closed. If the sup- ply fan is ON, the control determines if the unit is in the OCCUPIED mode. If unit is in the OCCUPIED mode, the dampers open. If unit is in the UNOCCUPIED mode, the dampers close.

FILTER STATUS CONTROL Ð This control sequence moni- tors one or more air¯ow switches which measure the dif- ferential pressure between the upstream and downstream side of a ®lter.

When the ®lter becomes dirty or needs to be replaced, the air¯ow switches send a discrete signal to the processor mod- ule. This, in turn, generates an alarm at the Local Interface Device or Building Supervisor.

FAN CONTROL Ð The supply fan is started or stopped based on the occupancy schedule, adaptive optimal start, night- time free cooling, unoccupied heating, unoccupied cooling, demand limiting, night purge, or timed override.

The start of an occupied period is determined by either the occupancy schedule or optimal start. If optimal start is not selected, the supply fan starts at the occupied time en- tered in the occupancy schedule. If optimal start is selected, the fan starts at the calculated start time. The fan stops at the unoccupied time entered in the occupancy schedule. (Timed override may be used to extend the occupied period between 1 and 4 hours.)

During the unoccupied period, whenever the space tem- perature falls below the unoccupied heating set point or rises above the unoccupied cooling set point, the supply fan en- ergizes and runs until the space temperature returns to within the required limits.

The supply fan can also run between the hours of 3:00 am and 7:00 am when the unit is in the Nighttime Free Cooling mode to pre-cool the space prior to the Occupied period.

Constant volume units that are subject to demand limiting stop the supply fan whenever a loadshed command is re- ceived from the CCN Loadshed option. The supply fan re- mains OFF until the loadshed command is cleared or the in- ternal maximum loadshed timer expires.

NIGHTTIME FREE COOL (NTFC) Ð Nighttime free cool- ing is used to start the supply fan to precool the building's interior using outside air. This delays the need for mechani- cal cooling when the system enters the Occupied mode.

The system determines if the outside conditions (tempera- ture and enthalpy) are suitable for outside cooling. If so, the supply fan is energized and the dampers modulate open. Once the space has been sufficiently cooled, the fan stops.

If the outside air conditions are not suitable, the fan remains OFF.

The unit must have mixed-air dampers to operate NTFC.

NTFC is scheduled to run only between the hours of 3:00 am and 7:00 am.

NIGHT PURGE Ð During the unoccupied period, this fea- ture starts the fans and opens the mixed-air dampers to re- move stagnant air and airborne pollutants from the building space.

If the current time is within the con®gured night purge duration, the control reads the outdoor air temperature and determines the mixed-air damper position. If the outdoor air temperature is less than the con®gured NTFC lockout tem- perature, the system sets the mixed-air dampers at the con- ®gured low temperature position. If the outdoor-air temperature is greater than the NTFC set point, or the enthalpy is high, the system sets the dampers at the con®gured high tempera- ture position.

When the outside-air temperature is below the NTFC set point and the low temperature night purge damper position is set to zero, night purge is not performed. Also, when the outside air temperature is above the NTFC set point and en- thalpy is high, if the high temperature night purge damper position is set to zero, night purge is not performed.

Night purge ends when the occupied time period begins.

QUICK TEST Ð The Quick Test is initiated and controlled at the local interface device (HSIO). It allows the service person or building owner to test all inputs and outputs of the PIC controls. When used, it displays all current values of input channels and allows the user to exercise all output channels.

Quick test suspends all process algorithms and forces all outputs with a service priority.

All service forces are removed when Quick Test is exited and control is returned to the process algorithms.

ANALOG OUTPUT TEMPERATURE CONTROL/ PREHEAT COIL CONTROL Ð The analog output tem- perature control adjusts an analog output to a ®xed set point, based on any analog temperature sensor connected to the unit. (Applicable sensors are: space temperature sensor, outside- air temperature sensor, mixed-air temperature sensor, supply- air temperature sensor, and return-air temperature sensor.)

If the fan is ON, the control identi®es the controlling tem- perature sensor, reads the sensor and compares the tempera- ture to the con®gurable set point. It then calculates the tem- perature required to satisfy the conditions.

The calculated value is compared to the actual tempera- ture and the corresponding output is modulated to the required position.

The preheat coil control adjusts the steam or hot water valve. The valve is modulated to raise the temperature of incoming outside air. The control uses a sensor downstream from the preheat coil to monitor the air temperature.

If the supply fan is OFF, the heating valve is modulated to maintain the desired minimum duct temperature (fan off value).

If the supply fan is on and the entering-air temperature is below the set point value, the heating valve is modulated to obtain the desired leaving-air temperature.

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Contents Installation, Operation, Start-Up Instructions ContentsGeneral Safety ConsiderationsInstallation Page ABX IGVPIC VAVDirect Expansion FMB Ð Filter Mixing BoxMXB Ð Mixing Box Normally ClosedControl Box for Remote Mounting AFS AotcAQ1 AQ2PIC Section Control Box Component Arrangements, 39L PIC Section Control Box Component Arrangement, 39NX Sizes PIC Section Control Box Component Arrangement, 39NX Sizes Page Input and Output Points AddressUnit 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 Junction Box Connections for Optional Remote Control Box Terminal SignalValve Assembly Typical Hot Water Valve Wiring Chilled Water Valve Wiring Duct Static Pressure ProbeNema Ð National Electrical Manufacturers Association Resistance Temperature OhmsMixed-Air Temperature Sensor HH79NZ021 Installation Enthalpy Control Settings Supply/Return Air Temperature Sensor HH79NZ019COI L Comno Wall-Mounted Relative Humidity Sensor Fig Duct-Mounted Relative Humidity Sensor Locations Air¯ow Switch P/N HK06WC030 CO2 Sensor Accessories CGCDXSEN002A00CGCDXSEN003A00 CGCDXGAS001A00Air Quality CO2 Sensor Wall Mount Version Shown CO2 Concentration PPMOAC Pressure Transducers Recommended Sensor Device Wiring Manufacturer Part NumberProcessor Sensor Module PIN noField Wiring of Sensors Recommended Actuators StrokeField-Supplied Mixing Box Actuator Signal Wiring HAND/OFF/AUTO Switch Tran Ð Transformer High-Pressure Switch Remove JumperEvacuation Supply Fan Contactor Fire Shut Down Terminal BlockPres 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 Pulse-Type Meter Wiring Control SystemCCN Communication Wiring AHU Air Handling UnitRelay Module Outdoor Air ThermostatOperative USE Keys Local Interface Device Key UsageFunction USE Keys Status History Schedule Service Set Point Test Functions and SubfunctionsSUB Function Number OavpControl Operation Operation Keyboard Display Description EntryKeyboard Directory StatusInputs VAV Direct Expansion Oavp Ð Outside Air Velocity Pressure AIRQUAL1 SET Point Quick Test History Keyboard Display Comments Entry Response Example 1 Ð Reading Alarm CodesExample 2 Ð Reading Current Operating Modes Alarms Display CodesForce States Display DescriptionState of Items Controlled Example 3 Ð Forcing An Input ValueExample 4 Ð Forcing An Output Value Relay StagesExample 5 Ð Using Quick Test Example 6 Ð Logging On and Logging Off Service FunctionKeyboard Display Comments Entry Response To LOG on To LOG OFFService Conguration Ranges and Defaults Analog Output Temperature Control Example 9 Ð User Congurations Example 7 Ð Reading and Changing Factory CongurationsExample 8 Ð Conguration of Measurements Example 12 Ð Conguration of Loadshed Example 11 Ð Conguration of Space Temperature ResetExample 10 Ð Conguration of Heating Coil Example 13 Ð Conguration of Fan Tracking Example 14 Ð Conguration of Alarm LimitsExample 15 Ð Conguration of Analog Temperature Control Example 16 Ð Conguration of Discrete Temperature Control Example 17 Ð Service History CongurationExample 18 Ð Service/Maintenance Alarm Conguration Set Point Ranges and DefaultsExample 20 Ð Reading and Changing System Set Points Example 21 Ð Setting of Time and DateExample 22 Ð Setting Daylight Savings Time Example 23 Ð Setting of Holidays Schedule I Sample Time SchedulePeriod 1 Dene schedule period Example 24 Ð Using the Schedule FunctionKeyboard Display Comment Entry Response Programming Period For this example, Period 6 is used for holiday only Constant Volume and Variable Air Volume Units Control Operating SequencePage Page MAT Ð Mixed-Air Temperature OAT Ð Outdoor-Air TemperatureIAQ Indoor-Air QualityConstant Volume Units Only CCV Ð Cooling Coil Valve RAT Ð Return-AirDX Submaster Gain Control Operation Variable Air Volume Units Only Page Outside Air OACConstant Outside Air Oavp Ð Outside Air Velocity Pressure102 START-UP Initial CheckTest of Input Signals Keyboard Display COMMENTS/ACTION Entry ResponseKeyboard Display COMMENTS/ACTION Entry Response FSD NRM FollowingTest of Output Signals For Variable Air Volume UnitsTest of Output Options Using Option Module Electric Heater TestControl Loop Checkout Direct Expansion DX Cooling TestDigital DC Volt Meter vs DC Milliamp Meter DC Milliamps DC VoltageValve Troubleshooting Recommended Gain Starting ValvesTypical Linkages Example 25 Ð Forcing An OutputIGV % HCV 10/FORCEDExit Test Control Module TroubleshootingExample 26 Ð Heating Coil Valve Test Way Normally Open Dsio Unit Troubleshooting Problem Possible Cause Corrective ActionHCV, CCV, IGV Malfunctioning IAQ featuresOAC malfunctioning 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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