SECTION 15864 DUCTLESS SPLIT-SYSTEM AIR-CONDITIONING UNITS
PART 1 - GENERAL
1.1 SUMMARY
A. This Section includes split-system air-conditioning units consisting of separate evapo- rator-fan and compressor-condenser components. Units are designed for exposed mounting.
B. Factory pre-insulated refrigerant line sets.
1.2 DEFINITIONS
A. Evaporator-Fan Unit: The part of the split-system air-conditioning unit that contains a coil for cooling and a fan to circulate air to conditioned space.
B. Compressor-Condenser Unit: The part of the split-system air-conditioning unit that contains a refrigerant compressor and a coil for condensing refrigerant.
1.3 SUBMITTALS
A. Product Data: Include rated capacities; shipping, installed, and operating weights; fur- nished specialties; and accessories for each type of product indicated. Include perfor- mance data in terms of capacities, outlet velocities, static pressures, sound power char- acteristics, motor requirements, and electrical characteristics.
B. Drawing showing layout, dimensions and materials used for the protective guard which is to surround Evaporator-Fan Unit. Clearly show how guard is to be mounted and also how access to unit for maintenance will be provided for.
C. Maintenance Data: For split-system air-conditioning units to include in maintenance manuals specified in Division 1.
1.4 QUALITY ASSURANCE
A. Product Options: Drawings indicate size, profiles, and dimensional requirements of split-system units and are based on the specific system indicated. Other manufacturers' systems with equal performance characteristics may be considered.
B. Electrical Components, Devices, and Accessories: Listed and labeled as defined in NFPA 70, Article 100, by a testing agency acceptable to authorities having jurisdiction, and marked for intended use.
1.5 COORDINATION
A. Coordinate size and location of concrete bases for units. Cast anchor-bolt inserts into bases. Concrete, reinforcement, and formwork are specified in Division 3 Section "Cast-in-Place Concrete."
1.6 WARRANTY
A. General Warranty: Special warranty specified in this Article shall not deprive Owner of other rights Owner may have under other provisions of the Contract Documents and shall be in addition to, and run concurrent with, other warranties made by Contractor under requirements of the Contract Documents.
B. Warranty Period: One year from date of substantial completion for general manufac- turer’s parts and defects warranty. The compressor shall have a warranty of 6 years from data of substantial completion.
1.7 EXTRA MATERIALS
A. Furnish extra materials described below that match products installed and that are packaged with protective covering for storage and identified with labels describing contents.
1. Filters: One set of filters for each unit.
PART 2 - PRODUCTS
2.1 MANUFACTURERS
A. Manufacturers: Subject to compliance with requirements, provide products by one of the following:
1. Carrier Corp.
2. Mitsubishi Electronics America, Inc.; HVAC Division.
2.2 REFRIGERANT & EFFICIENCY
A. Refrigerant to be R410A.
B. Efficiency shall meet or exceed SEER 13.0
2.3 WALL OR CEILING-MOUNTED, EVAPORATOR-FAN COMPONENTS
A. Cabinet: Formed of high strength molded plastic or formed metal with front panel ac- cess for filter. Color shall be white. Unit to be mounted to wall utilizing factory sup- plied mounting plate.
1. Indoor unit shall be factory assembled, wired and tested. Contained within the unit shall be all factory wiring and internal piping, control circuit board and fan motor. The unit in conjunction with the wired, wall mounted controller shall have a self-diagnostic function, 3-minute time delay mechanism, and auto restart function, and a test run switch. Indoor unit and refrigerant pipes shall be purged with dry nitrogen before shipment from the factory.
B. Refrigerant Coil: Copper tube, with mechanically bonded aluminum fins, complying with ARI 210/240, and with thermal-expansion valve.
1. A condensate pan and drain shall be provided under the coil.
C. Fan and Motor: Centrifugal fan, directly driven by multi-speed, electric motor with in- tegral overload protection; resiliently mounted, and permanently lubricated bearings.
D. Filters: Permanent/removable, cleanable.
E. Protection Guard: Guard shall be fabricated as a heavy cage suitable to protect the unit in a Gym environment. Allow for normal maintenance access without totally removing guard assembly.
2.4 AIR-COOLED, COMPRESSOR-CONDENSER COMPONENTS
A. Casing: Steel, finished with baked enamel, with removable panels for access to con- trols, weep holes for water drainage, and mounting holes in base. Provide brass service valves, fittings, and gage ports on exterior of casing.
B. Compressor: Hermetically sealed with crankcase heater and mounted on vibration iso- lation. Compressor motor shall have thermal- and current-sensitive overload devices, start capacitor, relay, and contactor.
1. Compressor Type: Rotary.
2. Variable Speed – Compressor speed to be driven by inverter circuit. Compressor speed shall dynamically vary to match the room load.
3. Top prevent liquid from accumulating in the compressor during the off cycle, a minimal amount of current shall be intermittently applied to the compressor mo- tor to maintain enough heat.
C. Refrigerant Coil: Copper tube, with mechanically bonded aluminum fins, complying with ARI 210/240, and with liquid subcooler. Refrigerant flow from the condenser shall be controlled by means of linear expansion valve (LEV) metering orifice. The LEV shall be controlled by a microprocessor controlled step motor.
1. Special Coil Coating Requirements: All condensing unit coils shall be provided with the following Heresite P-413C baked phenolic coating:
a. Finned tube coils shall be protected with a pure phenolic thermosetting res- inous coating. Metal preparation to provide a surface profile shall include degreasing and phosphatizing by immersion.
b. The coating shall be applied in multiple coats by immersion. After each immersion, the coating shall be partially cured in an oven. Following the final immersion and the application of one (1) spray coat, the coating shall be totally cured in an oven.
c. The total D.F.T. of the coating shall be approximately 2 mils, thereby providing good protection without adversely affecting heat transfer. D.F.T. varies depending upon fin spacing and the number of tube rows in depth.
The coating shall withstand dry heat up to 205ºC. (400ºF.), and show no sign of attack after 6,000 hours of salt spray test to A.S.T.M. Specification B117.
d. The coating shall be Heresite P-413C baking phenolic with plasticizer or approved equal.
D. Fan: Aluminum-propeller type, directly connected to motor.
E. Motor: Permanently lubricated, with integral thermal-overload protection.
F. Mounting Base: Concrete Pad or wall support brackets as indicated on the plans.
2.5 CONTROL
A. The control system shall consist of two microprocessors, one on each indoor and out- door unit, interconnected by a single non-polar two-wire cable. Field wiring shall run directly from the indoor unit to the wall-mounted controller with no splices. For A- Control, a three conductor 14 ga AWG wire with ground shall provide power feed and bi-directional control transmission between the outdoor and indoor units. Where sepa- rate power is supplied to the indoor and outdoor units, a tow 20 ga AWG wire shall be run between the units to provide forbid-directional control communication.
B. The system shall be capable of automatic restart when power is restored after power in- terruption, the system shall have self-diagnostic ability, including total hours of com- pressor run time. Diagnostic codes for indoor and outdoor units shall be displayed on the wired controller panel.
C. The microprocessor located in the indoor unit shall have the capability of monitoring return air temperature and indoor coil temperature receiving and processing commands from the wired controller, providing emergency operation and controlling the outdoor unit.
2.6 ACCESSORIES
A. Thermostat: Low voltage with subbase to control unit, compressor, and evaporator fan.
1. Compressor time delay.
2. 24-hour time control of system stop and start.
3. Liquid-crystal display indicating temperature, set-point temperature, time setting, operating mode, and fan speed.
4. Fan-speed selection, including auto setting.
B. Automatic-reset timer to prevent rapid cycling of compressor.
C. Refrigerant Line Kits: Soft-annealed copper suction and liquid lines factory cleaned, dried, pressurized, and sealed; factory-insulated suction line with flared fittings at both ends.
PART 3 - EXECUTION
3.1 INSTALLATION
A. Install units level and plumb.
B. Install evaporator-fan components using manufacturer's standard mounting devices se- curely fastened to building structure.
C. Install ground-mounted, compressor-condenser components as indicated on the Draw- ings. Include supports / wall mount brackets as required. Wall brackets to be fabricat- ed using Stainless Steel material.
D. Connect precharged refrigerant tubing to component's quick-connect fittings. Install tubing to allow access to unit.
E. Exterior refrigerant tubing insulation shall be field coated with UV resistant paint to preserve and protect insulation from UV exposure.
F. Install condensate piping down inside wall and stub out to grade. Route as shown on plans.
3.2 CONNECTIONS
A. Install piping as indicated on drawings and according to manufacturers recommenda- tions. Provide any accessories as may be required.
B. Install piping adjacent to unit to allow service and maintenance.
C. Unless otherwise indicated, connect piping with unions and shutoff valves to allow units to be disconnected without draining piping. Refer to piping system Sections for specific valve and specialty arrangements.
D. Condensate drain connections shall be made with Schedule 40 PVC pipe.
E. Ground equipment.
1. Tighten electrical connectors and terminals according to manufacturer's pub- lished torque-tightening values. If manufacturer's torque values are not indicated, use those specified in UL 486A and UL 486B.
3.3 FIELD QUALITY CONTROL
A. Installation Inspection: Engage a factory-authorized service representative to inspect field-assembled components and equipment installation, including piping and electrical connections, and to prepare a written report of inspection.
B. Leak Test: After installation, charge system and test for leaks. Repair leaks and retest until no leaks exist.
C. Operational Test: After electrical circuitry has been energized, start units to confirm proper motor rotation and unit operation. Remove malfunctioning units, replace with new components, and retest.
D. Test and adjust controls and safeties. Replace damaged and malfunctioning controls and equipment.
3.4 COMMISSIONING
A. Engage a factory-authorized service representative to perform startup service.
B. Verify that units are installed and connected according to the Contract Documents.
C. Lubricate bearings, adjust belt tension, and change filters.
D. Perform startup checks according to manufacturer's written instructions and do the fol- lowing:
1. Fill out manufacturer's checklists.
2. Check for unobstructed airflow over coils.
3. Check operation of condenser capacity-control device.
3.5 DEMONSTRATION
A. Engage a factory-authorized service representative to train Owner's maintenance per- sonnel to adjust, operate, and maintain units.
1. Train Owner's maintenance personnel on procedures and schedules for starting and stopping, troubleshooting, servicing, and maintaining units.
2. Schedule training with Owner with at least seven days' advance notice.
END OF SECTION
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