Carrier 40QNQ, 40QNC Service, Refrigerant Charging, Pump-down Procedure, Filter Drier

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SERVICE

!WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury or death.

Before installing, modifying, or servicing system, main electrical disconnect switch must be in the OFF position. There may be more than 1 disconnect switch. Lock out and tag switch with a suitable warning label.

Pump-down Procedure

The system may be pumped down in order to make repairs on the low side without losing complete refrigerant charge.

1.Attach pressure gage to suction service valve gage port.

2.Front-seat the mixed phase line valve.

!CAUTION

UNIT DAMAGE HAZARD

Failure to follow this caution may result in equipment damage or improper operation.

The unit coils hold only the factory-designated amount of refrigerant. Additional refrigerant may cause units to relieve pressure through the compressor internal pressure relief valve (indicated by a sudden rise of suction pressure) before suction pressure reaches 20 psig. If this occurs, shut off unit immediately then front-seat the suction valve and remove and recover excess refrigerant following accepted practices.

3.Start unit and run until suction pressure reaches 5 psig.

4.Shut unit off and front-seat suction valve.

5.Depressurize low side of unit and recover refrigerant fol- lowing accepted practices.

Filter Drier

Whenever the filter drier is exposed to the atmosphere it must be replaced. Only use factory specified liquid-line filter driers with rated working pressures less than 600 psig.

NOTE: Do not install a suction-line filter drier in the mixed phase line.

Refrigerant Charging

!WARNING

PERSONAL INJURY AND/OR EQUIPMENT DAMAGE HAZARD

Failure to follow this warning could result in personal injury and/or equipment damage.

Wear safety glasses and gloves when handling refrigerant. Do not overcharge system - this can cause compressor flooding.

All units are shipped with the refrigerant charge listed on nameplate.

NOTE: Do not vent or depressurize unit refrigerant to atmosphere. Remove and recover refrigerant following accepted practices.

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Contents Safety Considerations 40QNC, QNQ UnitDimensions Indoor Dimensions OutdoorClearances Outdoor Clearances IndoorCoil Facing Wall --- in. mm Fan Facing Wall --- in. mm Parts List System RequirementsUser Interface Power and Connecting Cables Field SuppliedAccessories Operating RangeConsider System Requirements InstallationComplete Pre-installation Checks Refrigerant Line RoutingMounting on Ground Side Or Bottom PipingMounting on Roof Connection at Outdoor Unit Complete Outdoor Refrigerant Piping Connec- tionsMounting Unit on Wall 38HDF UnitsPower Wiring Complete Outdoor Power and Control Wiring38QRF Units 38QRF Control Terminal Strip 38HDF / 38QRF Electrical Data 40QNC, QNQ Fan Coil Electrical Data40QNC01824 Matched with 38HDF Typical Wiring Schematic 40QNQ018,024 Matched with 38QRF Typical Wiring Schematic 40QNC030, 036 Matched with 38HDF Typical Wiring Schematic 40QNQ030, 036 Matched with 38QRF Typical Wiring Schematic Run Power Wiring for Indoor Unit Location of Piping, Hose, and WiringRemote Control Configuration Unit ConfigurationWired Control Control Wiring Between Indoor and Outdoor Units Wiring for Zone Manager Zone ManagerPreliminary Checks Using Vacuum PumpSTART-UP Evacuate and Dehydrate the SystemSet Unit in Test Mode Using Wired Control Test Mode Sequence of OperationSet Unit in Test Mode Using Wireless Control To Start the UnitRefrigerant Charging ServicePump-down Procedure Filter DrierGreen LED Indoor Unit Fault TroubleshootingFault Code TroubleshootingCatalog No 40QNC---Q---9SI

40QNQ, 40QNC specifications

The Carrier 40QNC and 40QNQ are advanced rooftop packaged units designed for efficient heating and cooling in commercial applications. These units are particularly known for their reliability, versatility, and energy-efficient performance, making them a preferred choice for building owners and HVAC professionals alike.

One of the standout features of the Carrier 40QNC and 40QNQ units is their variable-speed technology. This innovative system allows for precise control of airflow and temperature, ensuring that indoor environments maintain consistent comfort levels while minimizing energy consumption. The variable-speed compressor operates at different speeds based on the cooling demand, leading to reduced energy costs and improved overall efficiency.

In terms of energy performance, both models boast high Seasonal Energy Efficiency Ratios (SEER) and Heating Seasonal Performance Factors (HSPF). This not only contributes to lower energy bills but also helps in meeting energy efficiency standards and regulations in various regions. This makes the 40QNC and 40QNQ ideal for environmentally conscious building projects aiming for sustainability.

Another notable feature is the advanced microchannel coil technology utilized in these units. Microchannel coils are lighter, more compact, and provide enhanced heat exchange capabilities compared to traditional coils. This technology contributes to a more efficient refrigerant flow and ultimately leads to improved performance and durability of the unit.

Moreover, both models come equipped with a robust control system that enhances user interface. With smart thermostat compatibility, users can easily manage their building's climate remotely, ensuring optimal comfort and energy management. These systems are designed to integrate seamlessly with building management systems (BMS), allowing for greater control and optimization.

The construction of the Carrier 40QNC and 40QNQ also deserves mention. The units are built with durable materials designed to withstand harsh weather conditions, providing longevity and reliability. Additionally, the low sound levels produced by these units make them suitable for noise-sensitive settings, ensuring comfort without disruptive operation.

In summary, the Carrier 40QNC and 40QNQ are exemplary rooftop packaged units that combine advanced technology, energy efficiency, and reliable performance. Their variable-speed operation, microchannel coil technology, and robust control systems make them ideal solutions for commercial heating and cooling needs, catering to both comfort and sustainability.