SECTION ROOFTOP REPLACEMENT AIR UNITS

Transcription

1 PART 1 - GENERAL 1.1 RELATED DOCUMENTS A. Drawings and general provisions of the Contract, including General and Supplementary Conditions and other Specification Sections, apply to this Section. B. Related Sections include the following: 1. Division 7 Section "Manufactured Roof Specialties" for type and style of roof curbs and equipment supports. 2. Section Motors. 3. Section " Vibration and Seismic Controls for HVAC Piping and Equipment" for manufactured isolation bases. 4. Section Mechanical Identification. 5. Section Metal Ducts. 6. Section Duct Accessories. 7. Section "HVAC Instrumentation and Controls" for temperature-control devices, and control wiring and control devices connected to energy recovery units. 1.2 SUMMARY A. This Section includes rooftop heating and cooling units. 1.3 SUBMITTALS A. Product Data: Include manufacturer's technical data for each model indicated, including rated capacities of selected model clearly indicated; dimensions; required clearances; shipping, installed, and operating weights; furnished specialties; accessories; and installation and startup instructions. B. Shop Drawings: Detail equipment assemblies and indicate dimensions, weights, loadings, required clearances, method of field assembly, components, and location and size of each field connection. Detail mounting, securing, and flashing of roof curb to roof structure. Indicate coordinating requirements with roof membrane system. 1. Wiring Diagrams: Detail wiring for power, signal, and control systems and differentiate between manufacturer-installed and field-installed wiring. C. Commissioning Reports: Indicate results of startup and testing commissioning requirements. Submit copies of checklists. D. Maintenance Data: For equipment to include in the maintenance manuals. E. Warranties: Special warranties specified in this Section. 1.4 QUALITY CONTROL A. Fabricate and label refrigeration system to comply with ASHRAE 15, "Safety Code for Mechanical Refrigeration." Page 1 of 12

2 B. Energy Efficiency Ratio: Equal to or greater than prescribed by ASHRAE 90.1, "Energy Efficient Design of New Buildings except Low-Rise Residential Buildings." C. Coefficient of Performance: Equal to or greater than prescribed by ASHRAE 90.1, "Energy Efficient Design of New Buildings except Low-Rise Residential Buildings." D. Listing and Labeling: Provide electrically operated components specified in this Section that are listed and labeled. 1. The Terms "Listed" and "Labeled": As defined in the National Electrical Code, Article Listing and Labeling Agency Qualifications: A "Nationally Recognized Testing Laboratory" as defined in OSHA Regulation E. Comply with AGA Z223.1 for gas-fired furnace section. F. Comply with NFPA DELIVERY, STORAGE, AND HANDLING A. Deliver rooftop units as factory-assembled units with protective crating and covering. B. Coordinate delivery of units in sufficient time to allow movement into building. C. Handle rooftop units to comply with manufacturer's written rigging and installation instructions for unloading and moving to final location. 1.6 COORDINATION A. Coordinate installation of roof curbs, equipment supports, and roof penetrations with roof construction. Roof specialties are specified in Division 7 Sections. 1.7 WARRANTY A. General Warranty: The special warranty specified in this Article shall not deprive the Owner of other rights the Owner may have under other provisions of the Contract Documents and shall be in addition to, and run concurrent with, other warranties made by the Contractor under requirements of the Contract Documents. B. Special Warranty: A written warranty, executed by the manufacturer and signed by the Contractor, agreeing to replace components that fail in materials or workmanship, within the specified warranty period, provided manufacturer's written instructions for installation, operation, and maintenance have been followed. 1. Warranty Period, Compressors: Manufacturers standard, but not less than 5 years after date of Substantial Completion. 2. Warranty Period, Heat Exchangers: Manufacturers standard, but not less than 10 years after date of Substantial Completion. 1.8 EXTRA MATERIALS A. Furnish extra materials described below that match products installed, are packaged with protective covering for storage, and are identified with labels describing contents. Page 2 of 12

3 PART 2 - PRODUCTS 2.1 MANUFACTURERS 1. Fan Belts: One set for each belt-drive fan. 2. Filters: One set of filters for each unit. A. Available Manufacturers: Subject to compliance with requirements, manufacturers offering products that may be incorporated into the Work include, but are not limited to, the following: B. Manufacturers: Subject to compliance with requirements, provide products by one of the following: 1. Rooftop Units: a. York International Corp. b. Trane Company (The). c. Carrier Corp.; Carrier Air Conditioning Div. 2.2 ROOFTOP UNITS - GENERAL A. Rooftop Unit shall be completely factory assembled, piped, wired, tested and shipped in one piece with a single point power connection. Outside air system, return air system, filters, switches and supply air fan system shall be furnished factory installed. Units shall be specifically designed for outdoor rooftop application and include a weatherproof cabinet. Units shall have direct expansion cooling with natural gas, electric, hot water heat as scheduled and specified. Units shall be shipped fully charged with Refrigerant 22 or as scheduled. B. All units shall have decals and tags to indicate caution areas and aid unit service. Unit nameplates shall be fixed to the deadfront cover in the main control panel. Electrical wiring diagrams shall be attached to control panels. Installation and maintenance bulletins shall be supplied with each unit CABINET, CASING AND FRAME A. The frame and unit base shall be (14-gauge galvanized steel, nominal 18 ton through 30 ton units), (12-gauge galvanized steel, nominal 35 ton through 100 ton units). The unit base shall overhang the roof curb for water run-off and shall have a formed recess that seats on roof curb gasket to provide a positive weathertight seal. Exterior panels shall be constructed of 17-gauge galvanized steel. Access doors downstream of the supply air fan section shall include 20-gauge galvanized steel door liners. All side access doors shall seal to vinyl, dual durometer gasketing which use air pressure differential to guarantee sealing. B. Unit cabinetry shall incorporate a standing top seam and channeled surfaces at all joining sections. Top panels shall be cross-broken for water drainage. Unit cabinet shall be designed to operate at external static pressures up to 5.5 inches W.G. C. Exterior surfaces shall be phosphatized and coated with baked-on, light gray enamel which passes the government, 500 hour salt spray test. Access doors shall be supplied on both sides of every section with stainless steel hinges and a single point latch and service retainer. Access doors requiring mechanical fasteners are not acceptable. Page 3 of 12

4 D. Condensing unit section access doors shall have quick turn latches. E. Unit shall be completely insulated with one-inch thick neoprene coated glass fiber secured to side, top and end panels with adhesive and mechanical fasteners. Lifting brackets with lifting holes shall be provided on the unit base to accept cable or chain hooks. 2.4 CONDENSING SECTION A. Compressors shall be heavy-duty, reciprocating, semi-hermetic type with serviceable oil pump, unloaders and cylinder heads along with reversible, positive displacement oil pump, suction and discharge line service valves, crankcase heater and inherent solid state thermal overload protection. Scroll and reciprocating type hermetic compressors may be optioned, when approved by owner. Each compressor shall have its own completely independent refrigeration circuit including sightglass, filter-drier, manual shut-off valve and spring-type high-pressure relief valve. Compressor shall be isolated on spring mounts with vibration line isolators. Compressor capacity reduction shall be accomplished with cylinder unloading and/or hot gas bypass. B. The condensing unit section shall be open on the sides and bottom to assure complete access to and airflow through the coils. Condenser coils shall be multi-row type fabricated from seamless copper tubing mechanically bonded to rippled and corrugated aluminum fins. Condenser coil for each refrigerant circuit shall be provided with an additional circuit for a minimum of 15 degrees of subcooling. Each condenser coil shall be factory leak tested at 315 PSIG under water. Hail guards shall be provided to protect the coil fins from damage by handling and weather. C. Condenser fans shall be direct drive, propeller type designed for low tip speed and vertical air discharge. Fan blades shall be constructed of steel and riveted to an Iridite dipped steel center hub. D. Condenser fan motors shall be heavy-duty, inherently protected, three-phase non-reversing type with permanently lubricated ball bearings and integral rain shield. 2.5 COOLING COIL SECTION A. Evaporator coils shall be multi-row type fabricated from 5/8-inch O.D. seamless copper tubing mechanically bonded to rippled and corrugated aluminum fins. Two-row evaporator coils shall have a maximum of twelve fins per inch and three, four and five-row coils shall have a maximum of eight fins per inch. Coils shall be factory leak tested at 315 PSIG under water. The evaporator coil circuitings shall be fed with an adjustable thermal expansion valve (one per refrigerant circuit) with an external equalizer. The evaporator coil shall be circuited for a combination row/face split on 2 compressor units. B. Chilled water coils shall be multi-row type fabricated from 5/8" O.D. seamless copper tubing mechanically bonded to rippled and corrugated aluminum fins. Chilled water coils shall be available with a variety of coil circuitings, rows, and fins per inch selected from an ARI Certified Computer Program to match the cooling load. (Control of the chilled water coil shall be accomplished by a factory installed control package including a Page 4 of 12

5 three-way modulating control valve, piping and spring return valve operator). Chilled water coils shall be provided with vent and drain connections. C. A mastic coated primary drain pan shall be provided with the cooling coil and extend beyond the leaving side of the coil and underneath the cooling coil connections. The drain pan shall be connected to a threaded drain connection extended through the unit base. Units shall be provided with a secondary mastic coated drain pan connected to the primary drain pan. 2.6 HEAT EXCHANGER SECTION A. Heat exchanger shall be suitable for use with gas burners. The heat exchanger shall have a welded 430 stainless steel cylindrical combustion chamber and a 430 stainless steel header. Secondary heat exchanger surface shall be of corrosion resistant aluminized steel (stainless steel) tubing. A carbon steel heat exchanger surface shall not be acceptable. The heat exchanger design shall permit each section to freely expand and contract at its own rate, including each individual secondary tube. B. There shall be no baffles within the heat exchanger design except secondary surface tubing turbulators. There shall be no gasketed plates, bulkheads, or ports between the inside of the heat exchanger and the supply air stream. Cleanout of the heat exchanger and turbulators shall be accomplished without removing casing panels or passing soot through the supply air passages. A flame observation port shall be provided opposite the burner. The heat exchanger shall have a condensate drain. C. The burner shall be a forced draft type. The burner, controls and valves shall be housed within the integral burner vestibule. The vestibule door shall be hinged at the top and equipped with steel retainer rod to hold the door open for service. The burner shall be fire tested and adjusted at the factory. Final adjustments shall be made in the field at initial start-up by a qualified service organization. D. Modulating gas burner, if applicable, shall be capable of efficient operation from 33% through 100% of rated capacity. (Gas burners shall be forced draft type, complete with flame supervision, integral prepurge timing, combustion air proving switch, intermittent pilot with spark ignition, and a complete gas train. The gas train shall include the main gas valve, main pressure regulator, main shut-off cock, pilot gas valve, pilot pressure regulator, and pilot cock. (Units 400 MBH nominal output and larger shall have electronic flame supervision with 4-second time response.) 2.7 ELECTRIC HEAT A. Electric heating coils shall be constructed with low watt density nickel chromium elements. Safety controls shall include automatic reset high limit control for each heater element, a linear heat limiter in the discharge air stream of each heater bank, and line break protection in each heater circuit. Heating element branch circuits shall be individually fused to a maximum of 48 amps to meet NEC requirements. B. A solid-state control system with full magnetic line break contactors shall provide multiple stages of control. The electric heating section shall contain a single point electrical connection with a factory-mounted non-fused disconnect switch to provide power to the unit as well as the electric heat section. Page 5 of 12

6 2.8 HOT WATER HEAT A. Hot water coils, if applicable, shall be one or two-row type fabricated from l/2-inch O.D. seamless copper tubes mechanically bonded to rippled and corrugated aluminum fins. (Control of the hot water coil shall be accomplished by a factory installed control package including a three-way modulating control valve, piping and a spring return valve operator). 2.9 SUPPLY FAN SECTION A. Supply fans shall be double width, double inlet centrifugal type forward curved or airfoil as specified and scheduled. Nominal 18 ton through 30-ton units shall have two fans and nominal 35 ton through 100-ton units shall have a single fan. All fans shall be statically and dynamically balanced for quiet operation. The forward curved fan wheel and housing shall be fabricated from painted cold rolled steel on nominal 18 ton through 30-ton units and continuous galvanized steel on nominal 35 ton through 100-ton units. The airfoil fan wheel shall be Class II type and fabricated from aluminum with the fan blades continuously welded to the back plate and end rim. Units shall have solid steel fan shafts mounted in heavy-duty, L10 200,000-hour relubricative ball bearings. B. Fan motors shall be heavy-duty, 1800 RPM, open drip-proof type with relubricative ball bearings. The motor shall have a variable pitch sheave and an adjustable base for proper alignment and belt tension adjustment. The entire fan assembly shall be completely isolated from the unit bulkhead with neoprene gasketing and mounted on double deflection spring isolators FILTER SECTION A. The filter section shall be supplied complete with galvanized steel filter racks as an integral part of the unit. Filters shall be accessible from both sides of the unit. The filter section shall be as specified and scheduled RETURN AIR SECTION A. When specified and scheduled, return fans shall be centrifugal type forward curved or airfoil. Nominal 18 ton through 30-ton units shall have two fans and nominal 35 ton through 100 ton units shall have a single fan. All fans shall be statically and dynamically balanced for quiet operation. B. The forward curved fan wheel and housing shall be fabricated from painted cold rolled steel on nominal 18 ton through 30-ton units and continuous galvanized steel on nominal 40 ton through 100 ton units. The airfoil fan wheel shall be Class II type and fabricated from aluminum with the fan blades continuously welded to the back plate and end rim. Units shall have solid steel fan shafts mounted in heavy-duty, L10 200,000-hour relubricative ball bearings. C. Fan motors shall be heavy-duty, 1800 RPM, open drip-proof type with greaseable ball bearings. The motor shall have a variable pitch sheave and an adjustable base for proper alignment and belt tension adjustment. The entire fan assembly shall be completely isolated from the unit bulkhead with neoprene gasketing and mounted on double deflection, spring isolators. Page 6 of 12

7 2.12 OUTSIDE AIR SECTION A. The outside and return air section shall be designed to form a plenum. Outside air arrangement shall be as specified and scheduled for application ELECTRICAL A. Each unit shall be wired and tested at the factory before shipment. Wiring shall comply with NEC requirements and shall conform with all applicable U.L. standards. All wiring shall be number coded per the electrical wiring diagrams. All electrical components shall be labeled according to the electrical diagram and be U.L. recognized where applicable. Each unit (except condensing section only units) shall have a 115-volt control circuit transformer, 115-volt receptacle, system service switch, and control circuit fuse. B. The supply and return air fan, compressor and condenser fan motor branch circuits shall be individually fused. Contactors and inherent thermal overload protection shall be furnished for each compressor and condenser fan motor. The supply and return air fan motors shall have contactors and external overload protection. C. A terminal block shall be provided for the main power connection and a terminal board shall be provided for the low voltage control wiring. Knockouts shall be provided in the bottom of the main control panel for field wiring entrance. A separate keylocked control panel shall house all controls for the condensing section REFRIGERATION CONTROLS A. Each compressor circuit shall include a liquid line solenoid valve, oil pressure switch, high-pressure switch, low-pressure switch, compressor control circuit switch and pumpdown switch. Each refrigeration circuit shall have at least one condenser fan controlled from an ambient thermostat for positive head pressure control. An ambient thermostat shall prevent the refrigeration system from operating below 50 degrees F (adjustable) TEMPERATURE CONTROLS A. Units shall be provided with specified and scheduled control systems. All temperature control system components shall be completely factory wired and tested ELECTROMECHANICAL CONTROLS (if applicable) A. Control of the mechanical cooling and gas heating functions shall be by a 24 volt, mercury bulb type wall thermostat SOLID STATE CONTROLS (if applicable) A. Solid state controls shall be provided for wall thermostat and return air thermostat applications where the unit manufacturer provides all temperature control components including the thermostat, hot water, chilled water and steam valve motors; and/or the economizer damper motor. The solid state control system shall provide two or three-stage cooling; modulating cooling; two or three stage heating; modulating heating; modulating economizer operation; and automatic changeover of the cooling and heating functions. The solid-state control system shall include a solid-state thermostat, discharge Page 7 of 12

8 air sensor, central processor, electric heat sequencer, and economizer with enthalpy and low limit control. B. The central processor shall integrate the continuous input signals from the thermostat and discharge air sensor and translate them into the appropriate cooling, heating, or economizer action. The central processor and electric heat sequencer shall include an integral timing network to minimize the cycling of the heating and cooling functions. Night setback operation shall also be an integral part of the control system, automatically closing the outside air dampers and setting the thermostat back 5 F to 15 F from a single time clock without the use of an additional night setback thermostat DISCHARGE AIR CONTROLS (MICROPROCESSOR BASED) (if applicable) A. Discharge air controls shall be provided for use on mechanical or chilled water cooling applications. The discharge air control system shall be completely factory installed to control the discharge air temperature from a single sensor. The sensor shall be located at the discharge air opening. The discharge air controller shall have an adjustable temperature setting (40F to 90F) and an adjustable cycling rate (3 to 6 CPH). B. On mechanical cooling units, the discharge air controller shall operate the economizer and mechanical cooling stages. On multiple compressor units, the discharge air controller shall alternate circuit unloading between compressors. The economizer cycle shall include enthalpy control of the economizer dampers. The mechanical refrigeration system shall be locked out below 50F ambient (adjustable). C. On chilled water cooling units, the discharge air controller shall control the economizer and a three-way modulating chilled water valve. The economizer cycle shall include enthalpy control of the economizer dampers REMOTE MONITORING PANEL A. A remote monitoring panel shall be provided with system operation switches and signal lights for remote control and monitoring of unit functions. The panel shall include "Heat-Auto-Cool" system switch, "On-Off" fan switch, minimum outside air damper potentiometer and four signal lights to indicate supply fan operation, mechanical cooling malfunction, gas heat malfunction, and clogged filters. Two additional lights shall be provided on the remote monitor panel for field hook-up and monitoring of other system functions ROOF CURB A. A prefabricated 12-gauge galvanized steel mounting curb designed and manufactured by the unit manufacturer shall be provided for field assembly on the roof decking prior to unit shipment. The roof curb shall be a perimeter type with complete perimeter support of the air handling section and rail support of the condensing unit section. The curb shall be a minimum of 16 inches high and include a nominal 2 x 4-inch wood nailer strip. Gasketing shall be provided for field mounting between the unit base and roof curb. The roof curb shall be approved by the National Roofing Contractors Association ADDITIONAL EQUIPMENT A. The following additional equipment shall be provided. Page 8 of 12

9 2.24 MOTORS 1. An adjustable 0 to 8 minute timer lockout shall be provided on each compressor to prevent short cycling on safety control or power interruption. 2. Part winding start shall be provided on each compressor and each supply and return fan motor larger than 10 horsepower on 208, 230 or 460 volt units to provide two-step starting. 3. Hot gas bypass control shall be factory installed on each compressor circuit to provide capacity control by artificially loading the evaporator. Hot gas bypass control shall include a solenoid valve, hot gas bypass piping, and a hot gas bypass valve. The hot gas bypass valve shall be sized to modulate the full load. 4. Additional steps of cylinder unloading shall be provided on multiple compressor and single six-cylinder compressor units. Suction pressure switches shall control the cylinder unloaders on units with wall thermostat or return air temperature control. A unit mounted step controller shall control the cylinder unloaders electrically on units with discharge air temperature control. 5. A disconnect switch shall be provided to cut power to the entire unit before the control panel door can be opened. 6. An ionization type smoke detector equal to the Honeywell TC100D shall be factory mounted in the return or supply and return sections as required by code. Sensing tubing shall be strung across outlet openings and connected to the smoke detector sensing ports. Sensing tubing has several openings to get a full sampling and shall shut down the unit and shut outdoor air dampers when sensing smoke. 7. Optional isolation roof curb shall be furnished by the manufacturer of the unit. Isolation curb shall be of the size to match the exact dimensional criteria of the unit casing and factory mounting kits shall be furnished for field installation by the Contractor. A. Refer to Section "Motors" for general requirements for factory-installed motors. B. Motor Construction: NEMA MG 1, general purpose, continuous duty, Design B. C. Enclosure Type: Open, dripproof SOURCE QUALITY CONTROL A. Verification of Performance: Rate capacity according to ARI 210/240, "Unitary Air- Conditioning and Air Source Heat Pump Equipment." B. Verification of Performance: Rate capacity according to ARI 360, "Commercial and Industrial Unitary Air-Conditioning Equipment." 1. Sound Power Level Ratings: Comply with ARI 270, "Standard for Sound Rating of Outdoor Unitary Equipment." PART 3 - EXECUTION 3.1 EXAMINATION A. Examine roof for compliance with requirements for conditions affecting installation and performance of rooftop units. Do not proceed with installation until unsatisfactory conditions have been corrected. Page 9 of 12

10 3.2 INSTALLATION A. Install units according to manufacturer's written instructions. B. Install units level and plumb, maintaining manufacturer's recommended clearances. C. Curb Support: Install roof curb on roof structure, level, according to NRCA's written installation instructions. Install and secure rooftop units on curbs and coordinate roof penetrations and flashing with roof construction. D. Unit Support: Install unit on structural curbs and level. Coordinate wall penetrations and flashing with wall construction. 3.3 CONNECTIONS A. Piping installation requirements are specified in other Division 15 Sections. Drawings indicate the general arrangement of piping, fittings, and specialties. The following are specific connection requirements: 1. Install piping to allow service and maintenance. 2. Gas Piping: Conform to applicable requirements of Section "Facility Natural Gas Piping." Connect gas piping to burner, full size of gas train inlet, and provide union with sufficient clearance for burner removal and service. 3. Hot-Water Heating Piping: Conform to applicable requirements of Section "Hydronic Piping." Connect with shutoff valve and union or flange. B. Duct installation requirements are specified in other Division 15 Sections. Drawings indicate the general arrangement of ducts. The following are specific connection requirements: 1. Install ducts to termination in roof mounting frames. Where indicated, terminate return-air duct through roof structure and insulate space between roof and bottom of unit. C. Electrical: Conform to applicable requirements in Division 16 Sections. D. Ground equipment. 1. Tighten electrical connectors and terminals according to manufacturer's published torque-tightening values. Where manufacturer's torque values are not indicated, use those specified in UL 486A and UL 486B. 3.4 START UP SERVICE A. Verify that installation is as indicated and specified. B. Complete manufacturer's installation and startup checks and perform the following: 1. Level unit on housekeeping base, and flash curbs to unit and to roof. 2. Inspect for visible damage to unit casing. 3. Inspect for visible damage to furnace combustion chamber. 4. Inspect for visible damage to compressor, air-cooled condenser coil, and fans. 5. Verify that clearances have been provided for servicing. 6. Check that labels are clearly visible. 7. Clean furnace flue and condenser and inspect for construction debris. Page 10 of 12

11 8. Verify that controls are connected and operable. 9. Remove shipping bolts, blocks, and tie-down straps. 10. Verify that filters are installed. 11. Adjust vibration isolators. 12. Connect and purge gas line. 13. Check that burner and controls are suitable to operate at temperatures as low as minus 40 deg F. 14. Check acoustic insulation. 15. Check operation of barometric dampers. C. Lubricate bearings on fan. D. Check fan-wheel rotation for correct direction without vibration and binding. E. Adjust fan belts to proper alignment and tension. F. Start unit according to manufacturer's written instructions. 1. Perform starting of refrigeration in summer only. 2. Complete startup sheets and attach copy with Contractor's startup report. G. Check and record performance of interlocks and protection devices; verify sequences. H. Operate unit for an initial period as recommended or required by manufacturer. I. Perform the following operations for both minimum and maximum firing, and adjust burner for peak efficiency. Adjust pilot to stable flame. 1. Measure gas pressure on manifold. 2. Measure combustion-air temperature at inlet to combustion chamber. 3. Measure flue-gas temperature at furnace discharge. 4. Perform flue-gas analysis. Measure and record flue-gas carbon dioxide and oxygen concentration. 5. Measure supply-air temperature and volume when burner is at maximum firing rate and when burner is off. Calculate useful heat to supply air. 6. Check for backdraft under full operation. J. Calibrate thermostats. K. Adjust and check high-temperature limits. L. Check internal isolators. M. Check outside-air damper for proper stroke and interlock with return-air dampers. N. Check controls for correct sequencing of heating, mixing dampers, refrigeration, and normal and emergency shutdown. O. Start refrigeration and measure and record the following: 1. Coil leaving-air, dry- and wet-bulb temperatures. 2. Coil entering-air, dry- and wet-bulb temperatures. 3. Outside-air, dry-bulb temperature. 4. Air-cooled-condenser, discharge-air, dry-bulb temperature. Page 11 of 12

12 P. Measure and record the following minimum and maximum airflows. Plot fan volumes on fan curve. 1. Supply-air volume. 2. Return-air volume. 3. Relief-air volume. 4. Outside-air intake volume. Q. Simulate maximum cooling demand and check the following: 1. Compressor refrigerant suction and hot-gas pressures. 2. Short circuiting air through condenser or from condenser to outside-air intake. R. Verify operation of remote panel, including pilot-light operation and failure modes. Check the following: 1. High-limit heat exchanger. 2. Warm-up for morning cycle. 3. Freezestat operation. 4. Free-cooling mode, outside-air changeover. 5. Alarms. S. After starting and performance testing, change filters, vacuum heat exchanger and cooling and condenser coils, lubricate bearings, adjust belt tension, and check operation of power vents. 3.5 DEMONSTRATION A. Engage a factory-authorized service representative to train Owner's maintenance personnel as specified below: 1. Train Owner's maintenance personnel on procedures and schedules related to startup and shutdown, troubleshooting, servicing, and preventive maintenance. 2. Review data in the maintenance manuals. Refer to Section "Contract Closeout." 3. Review data in the maintenance manuals. Refer to Section "Operation and Maintenance Data." 4. Schedule training with Owner with at least 7 days' advance notice. END OF SECTION Page 12 of 12