York R-407C Harsh Environments Condenser and Evaporator Coil Protection, Building Exhaust Systems

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Application Data (continued)

For VAV applications, the YORK eco2 unit uses a VFD to modulate fan speed and maintain a constant duct static pressure. VFDs offer superior control over the operation of the unit at part load, and offer the addi- tional benefits of quieter and more efficient operation when compared to IGV.

HARSH ENVIRONMENTS – CONDENSER AND EVAPORATOR COIL PROTECTION

For harsh environmental conditions such as seashore applications, YORK offers three types of coil protec- tion: copper fin material, black fin and Technicoat coat- ings. YORK recommends that for corrosive environ- ments that copper fins be used to protect the evapora- tor and/or condenser coils. In areas where chemicals that can corrode copper are present, such as ammo- nia, YORK recommends that the black fin or Technicoat coating be used for maximum protection.

Copper Fin Condenser Coil

Copper fins can be used instead of aluminum for addi- tional corrosion protection, however it is not suitable for areas that are subject to acid rain or exposed to ammonia.

Pre-Coated Condenser Fins

Black fin coating (yellow fin for evaporator fins) is pre- coated application epoxy on aluminum fin stock to guard from corrosive agents and insulate against galvanic po- tential. It is used for mild seashore or industrial loca- tions. This can provide corrosion resistance comparable to copper fin coils in typical seashore locations.

Post-Coated Condenser Fins

Technicoat (a post-coated application of epoxy) can be used for seashore and other corrosive applications with the exception of strong alkalides, oxidizers, wet bro- mide, chlorine and fluorine in concentrations greater than 100 ppm.

Any of the above suitable options should be selected based on the particular project design parameters and related environmental factors. The application should be further reviewed and approved by the consulting en- gineer or owner based on their knowledge of the job site conditions.

BUILDING EXHAUST SYSTEMS

Building exhaust systems are often necessary when economizers are used to bring in outdoor air. Without proper building exhaust, the building may become over- pressurized. The exhaust system maintains the proper building pressure by expelling the appropriate amount of air from the building. Exhaust systems are typically designed to exhaust approximately 10% less air than what is entering the building. This provides a slight posi- tive pressure on the building.

100% modulating exhaust with building static pressure sensing and control

The 100% exhaust system can be configured with ei- ther control actuated dampers or VFDs for modulating control. The unit controller monitors the building pres- sure using a differential pressure transducer and main- tains the required building static pressure by modulat- ing the exhaust control. If the building has other means of exhaust or building pressure is not important, on/off or barometric control may be used.

100% modulating exhaust with fan on/off control

The 100% exhaust system can be configured for on/off operation eliminating the expense of the damper ac- tuators or VFDs. This exhaust system can be controlled by either the outside air damper position, or a building static pressure sensor.

Barometric exhaust

Barometric exhaust can be used when smaller amounts of air at low static pressure variations within the build- ing or other means of building exhaust are employed. Barometric exhaust is commonly used where there are only small fluctuations in building pressure or where building static pressure control is not necessary.

ROOF CURB

Optional 14-inch full-perimeter or open condenser roof curbs can be provided if necessary for mounting to the building roof. These curbs come disassembled and require installation in the field. For bottom supply and return duct openings, the curbs have matching con- nections to ease installation. A pipe chase that matches the rooftop unit is also included in the curb footprint for through-the-curb utility connections.

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YORK INTERNATIONAL

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Contents Packaged Rooftop Air Conditioning Units 407C Optimized Through 65 TonsTable of Contents Nomenclature Basic Model NumberIntroduction FEATURES/BENEFITSEcological and Economical Design Install with Ease and Safety ServiceabilityReliable Scroll Compressor Technology Introduction Physical Data Physical DataPhysical Data Cont’d Rigging Application DataLocation EconomizerBuilding Exhaust Systems Harsh Environments Condenser and Evaporator Coil ProtectionRoof Curb Given Selection ProcedureAcoustical Considerations Select UnitCooling Performance Data 50 Ton Model Cooling Performance Data 50 TON ModelCooling Performance Data 50 TON Model CONT’D Cooling Performance Data 55 Ton Model Cooling Performance Data 55 TON ModelCooling Performance Data 55 TON Model CONT’D Cooling Performance Data 60 Ton Model Cooling Performance Data 60 TON ModelCooling Performance Data 60 TON Model CONT’D Cooling Performance Data 65 Ton Model Cooling Performance Data 65 TON ModelCooling Performance Data 65 TON Model CONT’D 50 Through 65 TON Supply FAN Data Fan Performance50 Through 65 TON Supply FAN Data CONT’D 50 Through 65 TON Exhaust FAN Data Component Static Pressure Drops Inches of Water Column Filters Economizer Economizer Dampers Rigid Filter Manual or Load Definitions Electrical Service SizingElectrical Data CompressorsPremium Efficiency Supply and Exhaust FAN Motor ODP or TefcHigh Efficiency Condenser FAN Motors / EachControl Sequences for ALL Units Unoccupied / Occupied SwitchingControls GeneralVentilation Control Sequences Exhaust Control SequencesLOW Ambient Operation Smoke Purge SequencesVAV Specific Sequences Cooling OperationCooling Operation Thermostat Control Stand Alone ControlCV Specific Sequences Stage 1 Y1 CallPower Wiring SINGLE-POINT Power Supply WiringSINGLE-POINT Power Supply Wiring With NON-FUSED Disconnect SINGLE-POINT Power Supply Wiring with NON-FUSED DisconnectDUAL-POINT Power Supply Wiring DUAL-POINT Power Supply WiringField Control Wiring Field Control WiringDrawing General ArrangementBottom Supply Bottom Return Left or Right Rear Return Supply General Arrangement DrawingCurb Layout Drawing Curb Layout DrawingSupply AIR System Guide SpecificationsConstruction Bearings and DrivesAIR Inlet System Power SupplyAIR Filtering System Refrigeration SystemControls Accessories and OptionsEconomizers Condenser Coil Protection Relief SystemEvaporator Coil Protection Suction and Discharge Pressure Transducers moniYork International York International Proud Sponsor Olympic Team
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