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Packaged, Outdoor, Central Station Air Handling Units ME- Building Group

of 19 Revision Date: 02/05/16 Project & Bid Package File name: 237413 PACKAGED, OUTDOOR, CENTRAL-STATION AIR-HANDLING UNITS.doc

SECTION 237413 – PACKAGED, OUTDOOR, CENTRAL-STATION AIR-HANDLING UNITS

PART 1 - GENERAL

1.1 RELATED DOCUMENTS

A. Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 01 Specification Sections, apply to this Section.

1.2 SUMMARY

A. This Section includes packaged, factory-assembled, rooftop heating and cooling units consisting of structural frame, casing, fans, coils, filters, dampers, controls, piping, wiring, with components, material, accessories services, and testing necessary for a complete and fully functional system. 1. Units shall be provided with separately shipped roof curb.

B. Basis of Design: R-134a DX cooling unit.

1.3 SUBMITTALS

A. With the Bid, submit the following: 1. Basic drawing of unit showing configuration, dimensions, shipping splits, split weights,

location and size of natural gas, power, and drain connections. Include location and size of de-ionized water or steam piping connections for humidification alternates.

2. Product data with rated capacities of overall unit and major components of the refrigerant system, the heating system, and the humidifying system alternates.

3. A list of components or sub-assemblies requiring installation by the field contractor. 4. Fan performance curves, burner NOX and CO performance curves and sound

compliance data. 5. Preliminary sound power data at 32, 63, 125, 250, 500, 1000, 2000, 4000, and 8000 Hz

and sound pressure data. Sound pressure data shall be established as a distance of 10 feet from the operating unit.

6. Clearly specifiy additional installation requirements by others such as heat trace, drains, traps, etc. , that are necessary for the regular unit operations during ALL seasons.

B. Submittal Schedule: Within 1 week of the bid award, provide a submittal schedule including a table of recipients (with quantities) to be provided by Owner upon award.

C. LEED Submittals: 1. Product Data for Credit EA 4: Documentation indicating that equipment and refrigerants

comply. 2. Product Data for Prerequisite IEQ 1: Documentation indicating that units comply with

ASHRAE 62.1, Section 5 - "Systems and Equipment."

D. Shop Drawings: Indicate dimensions, weight loadings, weight distribution, and clearances required around and between construction elements. Include drawings detailing roof curb



assembly, mounting, securing, and flashing to the roof structure. Include gas train configuration and components including regulator.

E. Wiring Diagrams: For power supply wiring and ladder-type wiring diagrams of interlock and control wiring. Clearly differentiate between factory-installed and field-installed wiring. Include manufacturer's sequence of operation.

F. Controls: Control and instrument data sheets, sequence of operation, system architecture including interface to existing system, air handling unit schematic locating control devices and showing terminations to the DDC controller. Include electronic copies of AHU control programming including a licensed copy of the programming software.

G. Certificates: Certified performance data indicating entering and leaving air conditions. Include IRI and TSSA (in Canada) gas train certification and warranty certificates.

H. Weights and Scale Certificates: Shall be submitted to the Owner prior to shipment.

I. Operating and Maintenance Data: Prior to substantial completion of the project, submit complete copies of maintenance data and parts list, including operating and servicing procedures, preventative maintenance schedule and "troubleshooting" maintenance guide. Include certified as-built drawings of units.

J. Additional requirements: Verify with the architect for the condition of the roof with respect to roof slopes, unit locations, etc. before commencing with the fabrication.

K. Acessories: Drain traps (positive or negative, depending upon the project) will need to be provided by the Manufacturer, or clearly defined in the shop drawing that it will need to be provided by the Mechanical installer.

1.4 QUALITY ASSURANCE

A. Single-Source Responsibility: Rooftop air-conditioner, heating section, components, temperature controls, and accessories shall be from a single source. Furnish the name, address, and telephone number of the nearest field service organization with responsibility and accountability to answer and resolve problems regarding compatibility, installation, performance, and acceptance of units.

B. Chrysler Standards: The manufactured unit shall conform to the attached Chrysler noise specification. Manufacturer will review Chrysler Occupational Safety and Health Manuals, Volumes 1 and 2 to assure the contract work complies with these standards. .

C. ARI Compliance: 1. Comply with ARI 203/110 and ARI 303/110 for testing and rating energy efficiencies for

RTUs. 2. Comply with ARI 270 for testing and rating sound performance for RTUs.

D. ASHRAE Compliance: 1. Comply with ASHRAE 15 for refrigeration system safety. 2. Comply with ASHRAE 33 for methods of testing cooling and heating coils.



3. Comply with applicable requirements in ASHRAE 62.1, Section 5 - "Systems and Equipment" and Section 7 - "Construction and Startup."

E. ASHRAE/IESNA 90.1 Compliance: Applicable requirements in ASHRAE/IESNA 90.1, Section 6 - "Heating, Ventilating, and Air-Conditioning."

F. Regulatory Agencies, Codes and Standards: The provisions of the referenced Specifications and Standards, as applicable, govern the quality of materials and workmanship required under the Contract. Units shall bear CGA or ETL and CSA or ESA and TSSA in Canada, approval labels covering the entire unit, not just components.

G. Piping and Tubing: Perform welding, brazing, soldering and cutting work in conformance with requirements of Contract Documents and applicable provisions of the following: 1. ANSI B31.1. Power Piping with Current Addenda 2. ASME, Boiler and Pressure Vessel Code.

H. Materials: Units shall be manufactured with materials meeting the following standards: 1. ASTM – American Society for Testing and Materials A653/A653M, Specification for Steel

Sheet, Zinc-Coated (Galvanized) or Zinc-Iron Alloy-Coated (Galvannealed) by the Hot-Dip Process

2. ASTM – American Society for Testing and Materials, E84 – Test Method for Surface Burning Characteristics of Building Materials

I. Testing: The manufactured unit and its components shall be tested per the following: 1. NFPA 255 – Test of Surface Burning Characteristics of Building Materials 2. Testing and rating of fans shall be in accordance with AMCA standards. Tests shall be

conducted in a certified AMCA laboratory. 3. Refrigeration coils shall be selected, constructed, and tested in accordance with ARI

Standard 410. 4. Refrigerating system construction shall be in accordance with ASHRAE 15 "Safety Code

of Mechanical Refrigeration". 5. Energy Efficiency Ratio (EER) of rooftop units shall be equal to or greater than prescribed

by ASHRAE 90A "Energy Conservation in New Building Design". 6. Electrical components shall be listed by ULC and ESA, and have ULC and CSA labels, in

Canada. 7. Rooftop units shall be designed, manufactured, and tested in accordance with UL

requirements.

1.5 DELIVERY, STORAGE AND HANDLING

A. General: Units shall be delivered to and received by the Owner assigned installer. Equipment shall be completely shop assembled as much as possible. Provide a list detailing components or subassemblies to be shipped separately.

B. Unit Sections: Equipment too large for completely assembled shipment shall be shipped in as few sections as possible. Each section shipped shall be complete with interconnecting wiring, piping, and accessories required for final installation. Field assemblies required shall be only reconnecting piping, wiring, and casing. Open ends of sectional-piece units shall be provided with secure airtight and watertight closures during shipment.



C. Warehousing: The Owners intent is to store units on site for the minimum time required to stage the helicopter lifts. Warehousing costs if required to meet the delivery schedule are to be included in this contract.

1.6 Scheduling and sequencing

A. Following selection of the installer, manufacturer shall meet with the Owner and Contractor to develop approved shipping sequence. Provide notification to Owner and Contractor one week in advance of each shipping date.

1.7 SPECIAL WARRANTY

A. Parts, Refrigerant, and Labor: Provide written warranty, agreeing to replace/repair, within warranty period, parts and refrigerant having inadequate and defective materials and workmanship, including leakage, breakage, improper assembly, or failure to perform as required; provided manufacturer’s instructions for handling, installing, protecting, and maintaining units have been adhered to during warranty period. Warranty costs shall include the removal and reinstallation of associated equipment and materials as required to perform repairs.

B. Warranty Period: The warranty period shall be valid from the date of functional buyoff of the installed units by the manufacturer and the Owner.

1.8 MAINTENANCE MATERIAL SUBMITTALS

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. Fan Belts: One set for each belt-driven fan. 2. Filters: One set of filters for each unit.

PART 2 - PRODUCTS

2.1 GENERAL

A. Unit Performance Requirements: The manufacturer is responsible for sizing equipment to meet summer and winter leaving conditions as scheduled on the Drawings. Heating and cooling loads are to be verified by the manufacturer.

B. Silicone: Air handler components shall be silicone free, including lubricants, sealant, packings, coating, and gaskets.

C. Noise: Air handling unit, including compressors and condensers, shall not exceed a noise level of 80 dBA at 3 feet from the source

D. Service Connections: Piping and wiring shall be brought to the air handler through the curb, by the installer.

2.2 MANUFACTURED UNIT HOUSING



A. General: Unit shall be factory assembled designed for rooftop installation, and consist of compressors, condensers, evaporator coils, condenser fans, refrigeration with temperature controls, economizer, filters, and dampers. Unit shall be provided with initial charge of refrigerant.

B. General Fabrication Requirements for Casings: Formed and reinforced double-wall insulated panels, fabricated to allow removal for access to internal parts and components, with joints between sections sealed.

C. Structure: Unit shall have integral structure mounted on a continuous structural galvanized steel base such as 8 inch channels or I-beams to support a single lift onto roof curb. Unit base shall be equipped with a curb angle. Air handler support shall be extended to support the separate condenser on the curb. Air handler section shall be a one-piece construction if possible.

D. Weight: Sections of the air handler shall satisfy the size and weight requirements for helicopter lifts. (Size and weight limitations are inversely proportional due to downdraft and vary between 440 sq ft of horizontal surface area at 18,000 pounds to 250 sq ft of horizontal surface area at 21,000 pounds.) Manufacturer shall design the unit splits such that the number of helicopter lifts are kept to a minimum. Lifting lugs shall be provided, a minimum of 4 lugs per section to ensure proper rigging. Rigging and lifting safety instructions shall be attached to the unit.

E. Double-Wall Casing: Steel sheets, phosphatized, and finished with air-dry coating durable to withstand 670 consecutive hours of salt spray application in accordance with ASTM B117. Color is to match building siding. Structural members shall be minimum 14 gauge galvanized steel with access door frames constructed of minimum 18 gauge galvanized steel. Unit enclosure shall be solid double-wall construction with 2 inch thick, 1-1/2 lb density coated fiberglass insulation sandwiched between 18 gauge outer skin and 20 gauge inner liner. Casing walls shall have 18 gage outer panel and 20 gauge inner liner. Roof shall have 18 gage outer panel and 20 gage inner liner. Floor shall be fully welded 14 gage with 20 gage liner over insulation.

F. Drainage: The unit floor shall be fully welded galvanized steel with watertight weld wall seams 4 inches high, complying with ASHRAE 62.1, and capable of containing ponding water. Roof and wall seams shall be joined with continuous, silicone-free sealant. Fan and coil section deck shall be sloped to a trapped unit sump. Coils shall have drain pans piped to the sump. Supply fan floor section shall have single piece floor plate. Drain pans shall be suitable for field welding. Drains requiring drain traps shall be located such that the traps can be field installed under the unit and discharged through the unit base steel. Unit base steel shall include circular openings required for drain piping insertion. Galvanized piping for traps and drains, including anti-sweat insulation, shall be installed with the unit. If shipping restrictions prevent shop installation, the piping and insulation shall be shipped loose for field installation.

G. Insulation: Unit insulation, whether directly in air stream or not (i.e., under base, sandwiched between double-wall panels, or mastic coating on either side of base), shall meet NFPA 90 A flame and smoke ratings. Coatings and adhesives used in the construction of packaged rooftop air-conditioners shall meet a flame spread rating not over 25 and a smoke developed rating no higher than 50 as required in NFPA 90A.

H. Access Doors: Double–wall insulated gasketed type to provide access to each section of the unit. Doors shall have stainless steel piano hinges and latches. Door hinges and latches shall be positive action type and shall be easily adjustable to allow for a tight seal between the door



and the unit. Door latches shall have handles on both sides of the door. Doors shall be a minimum of 2 feet wide by 6 feet high. Access doors shall open against unit operating pressure. Provide stainless steel hold open device that attaches the door to the casing in the 180 degree open position, to prevent the wind from slamming the door closed.

I. Compartments: The gas train, control and burner exhaust fan cabinets shall be reach in type, attached to the air handling casing. Panels shall have gasketed doors; conduit and pipe panel penetration shall be sealed to prevent corrosion.

J. Provide non-conductive grating to raise the reach-in compartments up to the level of door threshold.

K. Finish: AHU and condenser shall be furnished with baked-on enamel prime and finish paint. Color shall match building siding . Metal siding that matches the building siding may be provided (as an alternate to painting) for the AHU. AHU manufacturer shall coordinate siding order with siding supplier. Equipment tags with AHU number and pertinent nameplate information shall be attached to the outside of each unit.

L. Airstream Surfaces: Surfaces in contact with the airstream shall comply with requirements in ASHRAE 62.1.

2.3 SUPPLY AIR FANS

A. General: Painted steel, centrifugal, double width, double inlet, belt-driven fans. (Unit supplier shall provide and replace sheaves as required to meet design conditions after testing and balancing air flows is done by others.) Motor and fan bearings shall be ball bearing type with 200,000 hours minimum L-10 life with grease lines extended outside the housing. Provide flexible connection between fan outlet and unit discharge outlet. Fan inlets shall be equipped with inlet screens.

B. Fan/Drive Mounting: Isolate fan/motor assembly from unit with 2 inch, factory set, spring vibration isolators. Provide thrust restraint isolation on the fan housing/fan board to assure smooth fan start-up and operation. Provide temporary restraints to prevent fan/drive movement during shipment of unit.

C. Fan Motor/Drive: 1800 RPM (or project specific), TEFC, premium efficiency, U-frame motor, (per Chrysler motor specification NPEM-105) electrically protected by dual element fuses in each leg and with motor overload protections in each leg. Motors shall be US Motors, Reliance, Siemens or Baldor. Motors shall be located for easy access and removal. Belt drives shall be selected for 150 percent service factor. Provide OSHA approved belt and shaft guards, with tachometer openings, and painted safety yellow.

2.4 ECONOMIZERS

A. Return- and outside-air dampers with neoprene seals, and hood. 1. Damper Motor: Fully modulating spring return with adjustable minimum position. 2. Control: Electronic-control system uses mixed-air temperature and selects between

outside-air and return-air enthalpy to adjust mixing dampers. 3. Power Exhaust Fan: 100 percent power exhaust fan, provide when scheduled on

Drawings.



B. Outdoor-Airflow Monitor: Accuracy maximum plus or minus 5 percent within 15 and 100 percent of total outdoor air. Monitor microprocessor shall adjust for temperature, and output shall range

from [2- to 10-V dc] [4 to 20 mA] <Insert value>.

2.5 COMPRESSOR/CONDENSING UNIT

A. General: Provide units specifically designed for outdoor installation on a roof curb, completely factory assembled, piped, insulated, internally wired, and tested. Provide interconnected piping and insulation required for connection to cooling coils. Refrigerant piping inside and outside of the unit shall be insulated. Refrigerant piping shall be broken as required for shipment. Units shall be shipped in one piece and come fully charged with refrigerant and filled with compressor oil. Units shall be furnished with baked-on enamel prime and finish paint having a color to match the AHU housing. Units shall be rated in accordance with ARI Standard 340/360. Refrigerant system shall be leak tested, evacuated and refrigerant charged at the factory. If refrigerant is shipped separate, the refrigeration system shall be nitrogen charged for shipping and site storage. Leak test reports, evacuation and charge reports are to be provided on each unit.

B. Compressors: Provide a minimum of 2 standard serviceable reciprocating semihermetic compressors, suction gas-cooled with integral vibration isolators, oil level sight glass, oil pump, oil filter screen, oil charging valve, and crankcase heaters which de-energize during compressor operation. Provide cylinder unloaders for capacity control, with minimum steps required to provide coil frost protection based on refrigerant circuit suction temperature. Provide thermal expansion valves, filter dryers, sight glasses, compressor service valves, liquid line service valves and individual circuits. Provide hot gas bypass on condenser system.

C. Compressor Controls: Provide the following compressor safety control features: 1. Low pressure cut-out, manual reset 2. High pressure cut-out, manual reset 3. Compressor motor overload protection, manual reset 4. Low oil pressure cut-out, manual reset 5. Adjustable low-ambient lockout 6. Anticycling timing device (to prevent excessive cycling and premature wear of the

compressors and contactors) and phase and brown-out protection 7. Time-delay relay to prevent simultaneous starting of compressors, except where

compressors are sequenced by motor-operated step controller. Relay motor shall be deactivated and returned to zero set after compressors are energized.

D. Condensers: Condensers shall be situated end-to end with the air handler and rated for 32 to 105 Deg F ambient design temperature. Condenser fans shall be zinc-plated steel, vertical discharge, propeller type, direct-driven fans and provided with weatherproof cover and weathertight slingers over the motor bearings. Fan motors shall be high efficiency, T-frame with permanently lubricated ball bearings and electrically protected by dual element fuses in each line and with motor overload protectors. Provide removable hail guard to protect condensing unit.

a. An optional Electronic Expansion Valve will be discussed with the owner on pricing in lieu of the traditional Mechanical Thermostatic Expansion Valve.

2.6 COOLING COILS



A. General: Aluminum plate fin and seamless copper tube type. Tubes shall be 1/2 inch diameter with 0.020 inch thick walls as a minimum. Fins shall have collars drawn, belled and firmly bonded to the tubes by means of mechanical expansion of the tubes. No soldering or tinning shall be used in the bonding process. Coils shall be mounted in a galvanized steel casing. Coils shall be mounted in the coil casing with same end connections accessible for service. Coils shall be removable from the unit through the piping enclosure. Coil sections shall be completely insulated. Each coil section shall have a drain pan and drain piped to the floor drain. Coil design and drainage shall be as required to prevent moisture carryover. Provide a low point drain and high point vent, and provide extensions where needed to drain the cooling coils for seasonal changes. Indicate the drain locations clearly in the drawing.

B. Refrigerant Cooling Coils: Equalizing type with vertical distributor to ensure each coil circuit receives the same amount of refrigerant. Coils shall be proof 450 psig and leak 300 psig tested with air pressure under water, then cleaned, dehydrated, and sealed with a holding charge of nitrogen. Coils shall be individually circuited with separate refrigeration circuit for each compressor. Coils shall be provided with not less than four rows and with no more than 8 fins per inch. Maximum face velocity of air passing over coil shall be 500 fpm.

2.7 DAMPERS

A. General: Provide opposed blade modulating return, outside air and burner bypass dampers and electric control system, with provisions for manually setting the outside air quantity from 0 to 100 percent. Return air dampers and opening shall be sized for 100 percent return. Return air damper shall operate inversely proportional to the outside air damper. Damper blades shall be minimum 16 gage galvanized steel with 3/4-inch jack shafts. Damper performance shall be AMCA certified. Bearings shall be machined bronze material.

B. Air Inlets: Provide steel walkway grating above return air inlet opening to the unit. Grating shall be in removable sections of 3 foot maximum length. Outside air intake hood shall be mushroom type, blown snow and blown rain proof with bird screen.

2.8 INDIRECT-FIRED HEATING

A. General: The heating section shall have an indirect natural gas section that is AGA, CGA, or ETL approved for both sea level and high altitude areas. Main system fan shall provide forced draft through the heat exchange section. An induced draft fan shall also be included to provide proper heating chamber balance.

B. Heat Exchanger: Primary heat exchanger shall be Series 400 stainless steel tubular design with 16-gage stainless steel primary and 18 gauge stainless steel secondary heat exchanger surfaces. Heat exchangers shall be factory pressure and leak tested. Heat exchanger supports shall allow stress free thermal expansion and contraction. Provide 2-foot by 2-foot rear access and explosion relief panel with chain restraint and observation port. Provide piped condensate drain.

C. Combustion Blower: Provide an integral combustion blower including direct-drive non-sparking impeller, TEFC motor with built-in thermal overloads. Provide combustion air inlet air filters.

D. Gas Burner: Burner shall be industrial type with air proving switch and ceramic cone to prevent flame impingement on sides of heat exchanger. Burner assembly shall house pilot burner (with



adjustable orifice), ignition module, flame monitoring sensor. Burner shall have full modulation with a 10:1 turndown ratio. Burner shall be suitable for burning natural gas with a nominal heating, value of 1000 Btu per cubic foot. Hard wired sensor shall be installed to the Air Handling Unit main controls, to address burner failure alarms immediately. An indication of the burner failure based on a calculated discharge temperature shall not be allowed.

E. 1. Basis-of-Design Product: Maxon Ovenpack II Model.

F. Gas Train: Gas equipment, piping and safety controls shall be installed and pressure tested by the manufacturer in accordance with IRI, FM and TSSA. Provide TSSA (in Canada) certification. Gas train is to be designed for supply from a building gas distribution system supplied at an inlet pressure of 30 psig. Motorized shut-off valves shall be lubricated plug type by Maxon. An AGA, CGA, or ETL rated inlet service shutoff valve and inlet strainer shall be provided. Gas pressure regulators, and gas train components requiring venting shall be separately vented to atmosphere outside of the housing and at least 10 feet from the outside air intakes. Manufacturer shall provide painted vent piping and piping attachments required for field installation. Gas components shall be enclosed in the service compartment integral with the unit housing.

G. Gas Train Safety Controls: The flame failure safeguard shall be a Honeywell RM 7838 burner control with a self check amplifier, panel mounted subbase, purge timer and ultraviolet flame sensor (Honeywell C7012E) with self-checking shutter. Remainder of the gas train safety controls shall include, but not be limited to: 1. Lubricated manual plug valves ahead of main and pilot regulators 2. Electronic spark ignition system 3. Pilot gas valve regulator 4. Pilot solenoid valve 5. Pilot airflow with adjustable pilot orifice 6. Auxiliary limit switches on motorized shutoff valves for monitoring status 7. Normally open solenoid vent valve 8. Pressure gauge before high pressure regulator 9. Normally open high and low pressure gas switches 10. Forced draft air flow switch 11. High temperature switch 12. Intake high limit switch 13. Smoke detector

2.9 HUMIDIFICATION

A. Unit shall have a humidification section capable of later installation of equipment required for either of the 2 humidification alternates. This includes having a unit of sufficient length and made of materials sufficient to withstand the corrosive effects of de-ionized water.

2.10 FILTER SECTION

A. Framing: Filter section to be suitable for 2-inch thick, 24-inch by 24-inch cartridge type filters. Provide access panels as required for replacing filters. Holding frames shall be factory fabricated of 16 gage galvanized steel. Mount panel filter media in supporting frames and coordinate supports to retain elements to provide a substantial, leakproof installation. Required



filter framing, hardware, and accessories shall be provided. Frames shall accept 24-inch by 24-inch bag secondary filters in the future.

B. Construction Filters: Filters shall be throwaway type, furnished as a part of this Contract. Each filter shall consist of a filter media, support grid, and enclosing frame. Filter shall be listed by Underwriters Laboratories as Class 2. Filter media shall have an average efficiency of 25 to 30 percent and an average arrestance of 90 to 92 percent in accordance with ASHRAE Test Standard 52.1-1992. Enclosing frame shall be rigid, high wet strength with diagonal support members. Provide two sets of filters with each unit, one for use during construction and one for final operation.

2.11 ROOF CURBS

A. General: Provide full perimeter curb designed to accommodate and support the entire custom rooftop air handier and condenser with a slope to match roof. Curb shall be factory constructed steel, designed to span purlin to purlin and flat to ensure that the unit is level, compensating for roof pitch. A roof plan will be distributed which will indicate design location and sloping required for the units. Installer shall be responsible for shimming the curb to maintain flatness. Roof curb shall be 16 inch high minimum at highest point of roof. Curb shall be manufactured according to National Roofing Contractors Association Guidelines. Supply air and return air ductwork, natural gas, and electrical service connections shall be through the bottom of the unit and inside of the roof curb.

B. Curb Sealing: Provide neoprene gasketing material for sealing between the air-handling unit assembly and the roof curb. Supplier shall provide appropriate flashing around the condenser and air handler to assure a watertight enclosure of the equipment and curb. Provide 12 gauge sheet metal cant for prevention of water ponding under the condensing unit and for insulation attachment around entire unit curb.

2.12 ELECTRICAL

A. Control Panel: Provide a NEMA 3R or NEMA 4 unit-mounted control panel. Provide a hinged "Lexan", or similar acrylic cover with magnetic latch over 480 volt components. Provide motor starters, transformers, fuses, and main disconnect switch, factory mounted and wired to the factory-furnished electrical devices. Burner controls and the DDC controller shall be as described in Article 2.12. Panel wiring, shall be a minimum of 14 gauge stranded copper wire, vinyl covered, and marked. Unit disconnect shall be a padlocked, fused type, knife blade, quick make/quick break and located on the control panel, no more than 6 feet 6 inches above the roof deck or access platform. Panels shall be constructed according to NEC regulations and shall be ULC listed. Provide a laminated wiring diagrams showing wiring shall be installed on the inside cover of each panel.

B. Other Panels: Provide separate control panels for the compressor/condenser unit to the same specifications as above except a breaker may be provided in lieu of a fused disconnect and the controller may be the manufacturers standard controller.

C. Convenience Outlet: The electrical compartment shall have a 115 VAC GF duplex convenience outlet and 1.5 kVA, 480-120V step-down transformer wired ahead of the main unit disconnect and separately fused for unit service.



D. Lighting: The reach in enclosure and each section in the AHU shall be provided with an incandescent light and marine type lens and guard. Bulbs shall be Tuff Duty and shall be shipped loose with the lenses and guards for installation by the field contractor. A light shall be provided on both sides of the supply fan. Provide a pole-mounted outdoor light fixture with a photo-eye and a manual light switch.

E. Provide a limit switch at each door with access to the air stream, hard-wired to shut down the unit upon opening the door, with a reset/restart pushbutton mounted on the outside of the control panel door.

F. Smoke Detectors: Where applicable, smoke detectors are to be provided, completely wired to the control panel for the electrical contractor to terminate for Fire Alarm systems or any other form of notification.

2.13 AUTOMATED CONTROLS

A. General: Provide control devices, associated standalone controller programming, existing front-end tie-in programming and graphics creation, start-up and commissioning services for the rooftop units. Furnish, factory-mount and wire rooftop unit mounted automatic temperature controls. Provide outdoor air sensors per the Drawings. Provide space temperature sensors and space humidity sensors per the Drawings. A daisy-chain type data-highway required for communication between AHU controllers shall be provided. 1. Provide compatible interface for central HVAC control workstation for the following:

a. Monitoring constant and variable motor loads. b. Monitoring variable-frequency drive operation. c. Monitoring cooling load. d. Monitoring economizer cycles. e. Monitoring air-distribution static pressure and ventilation air volume.

B. Control Architecture: Automated controls for the roof top air handling units shall be Direct Digital Controls utilizing compatible electronic temperature, humidity and pressure sensors and spring return Belimo electric/electronic damper actuators. Manufacturer shall demonstrate how the interconnecting communications can be accomplished to the satisfaction of the Owner prior to acceptance of control architecture.

C. Controls Subcontractor: The following work may be subcontracted to an Owner approved building management controls firm: 1. Submittals consisting of data sheets, system architecture including interface to existing

system, air handling unit schematic locating control devices and showing terminations to the DDC controller.

2. Supply of specified control components to unit manufacturer for factory installation including DDC controller and field components as shown in the control device coordination schedule.

3. Creation, installation and checkout of DDC programs to accomplish the specified controller stand alone sequence of operation.

4. Engineering, programming, graphics creation, and commissioning.

D. Specific Controls Devices: 1. DDC controller shall have a LCD display and keypad. Controller shall be cabinet mounted

with rail clamps on DIN- rail (clamps shipped with device).



2. Temperature sensors shall be Resistance Temperature Detector (RTD) type of 20,000 ohm. Sensors shall have + or - 1.0 deg F accuracy between 32 deg F and 212 deg F.

3. Duct temperature sensors shall be rigid stem or averaging type as required. 4. Relative humidity sensors shall be capacitance type with 10% to 90% range. Duct

mounted humidity sensors shall be provided with a sampling chamber. Current sensing relays used for proof-of-loading for fans shall be suitable for 2 to 200 amperes and shall have adjustable trip thresholds of plus or minus two percent of range. Each relay shall be provided with an LED to allow ready observation of the relay status.

5. Fan proof-of-flow switches shall be adjustable set point and differential pressure type. Switches shall be piped to fan discharge except where fans operate at less than one inch WC, they shall be piped across the fan. For fractional horsepower and non-ducted fans, relays or auxiliary contacts may be used. Maximum pressure rating shall be at least 10 inches WC.

6. Safety high limit shall be 135 degrees manual reset type. 7. Safety low limit shall be manual reset twenty foot limited fill type responsive to the coolest

section of its length. 8. Smoke detectors shall be ULC, photoelectric type located in the discharge air stream

inside the AHU or inside the supply ductwork. Smoke detectors shall be required in the return air ductwork, if used, and located at each floor level serviced by the AHU. Smoke detectors shall be fully accessible. Provide 2 sets of contacts for each smoke detector. One set of contacts shall be wired to the AHU control panel. If smoke is present, the smoke detector shall trip the supply air fan, closing the outdoor air damper and shutting down the heating and cooling systems. The secondary contacts shall be available for the Fire Alarm Contractor to connect to the Fire Alarm Monitoring System (24/7 location).

9. Damper actuators shall be Belimo ULC, direct coupled, electric actuators with position indicator, manual override crank, spring return, and an overload proof, brushless, DC motor with microprocessor control.

E. Monitoring Graphics: System graphics shall be accessible using the system multi-level penetration path. Direct access to graphics shall be by menu selection wherein the operator may optionally enter the name of the graphic system desired or select the desired graphic via cursor positioning on a scroll bar listing of graphics. Work with owner’s representative to develop revised graphics structure. In addition to graphics of building systems with dynamic data points, the following graphics shall be provided: 1. Revised system architecture incorporating new air handling unit graphics. 2. Text based building graphic providing point information for building units including unit

status, discharge temperature, outdoor air temperature, filter differential pressure, damper position, firing rate, fault status, space temperature and humidity for each air handling system.

3. Alarm screen 4. History and trending screen 5. Global command screen 6. (Note: Other screens may be added as required by manufacturer for system and AHU

diagnostics.) 7. Scheduling.

F. AHU I/O Summary: 1. AHU Fan Start/Stop Digital Output 2. AHU Door Limit Switch Status Digital Input 3. AHU Operating Status Digital Input



4. AHU Filter Differential Press Analog Input 5. AHU Discharge Air Temperature Analog Input 6. Outside Air Temperature Analog Input (For only 3 AHUs) 7. Zone Space Temperature Analog Input (1 per 6 AHUs) 8. Zone Space Humidity Analog Input (1 per 6 AHUs) 9. AHU Mixing Damper Output Analog Output 10. AHU Heating Output Analog Output

G. Control Device Schedule:

Device Furnished By Installed By

Controller Transformer for DDC Unit Mfr. Unit Mfr. Interposing Relay Kits for SF Unit Mfr. Unit Mfr. Current Transformer/Switches Unit Mfr. Unit Mfr. Filter & Gas Burner Differential Pressure Switches Unit Mfr. Unit Mfr. Gas Valve Status Relay Unit Mfr. Unit Mfr. Outside Air, Return Air & Burner Actuators Unit Mfr. Unit Mfr. Fan Reset Switches & Relay Unit Mfr. Unit Mfr. Local Selector Switches Unit Mfr. Unit Mfr. Burner Signal Conditioner Unit Mfr. Unit Mfr. Discharge Air Temp Sensor Unit Mfr. Unit Mfr. Space Temperature Sensor Unit Mfr. Site Contract Discharge Humidity Sensor Unit Mfr. Unit Mfr. Space Humidity Sensor Unit Mfr. Site Contract Burner Controls & Safeties Unit Mfr. Unit Mfr. Standalone DDC programs Unit Mfr. Unit Mfr. Site Data Highway Installation Site Contract Site Contract System Graphics & AHU Interface Unit Mfr. Unit Mfr. On-site Control Commissioning Unit Mfr. Unit Mfr Heat trace for burner condensate drain Unit Mfr. Unit Mfr.

H. AHU Operation: Use the attached Sequence of Operation for operating intent when developing manufacturers sequence of operation. During building construction the AHU shall be capable of being run manually from the local unit control panel prior to connection of the units to the network bus or the space sensors. Control panel shall have a lockable OFF - LOCAL MANUAL - REMOTE AUTO operation selector switch which, when placed in LOCAL MANUAL, shall control the unit to maintain the latest setpoints programmed into the unit. These setpoints shall be adjustable via the keypad on the AHU control panel. Prior to programming the AHU standalone controllers, the manufacturers sequence of operation and the initial settings for manual operation, shall be submitted for review and approval by the Owner. 1. Economizer control.

a. Outdoor-Airflow Monitor: Accuracy maximum plus or minus 5 percent within 15 and 100 percent of total outdoor air. Monitor microprocessor shall adjust for

temperature, and output shall range from [2- to 10-V dc] [4 to 20 mA] <Insert

value>.

I. CAPACITIES AND CHARACTERISTICS 1. See Schedule on Drawings.

PART 3 - EXECUTION



3.1 PRE-SHIPMENT REQUIREMENTS

A. General: Each air handler and associated condenser shall be assembled in the shop, piped, wired, programmed and operational performance proven prior to shipment. Manufacturer's quality of assurance certificate, indicating the date and results of shop performance tests shall be included with each unit.

B. Lockout Placards: Provide lockout placards supplied by a Chrysler approved vendor.

3.2 POST SHIPMENT REQUIREMENTS

A. Installation: Perform the pressure testing on the refrigerant piping before charging. Provide the services of a factory-authorized service representative to instruct installation contractor on the proper lifting, installation and reconnection of shipping splits. Verify integrity of refrigerant piping and initial refrigerant charge. If refrigerant piping split required, perform refrigerant piping pressure tests prior to refrigerant installation. Supply and install refrigerant required.

B. Start-Up Services: Provide the services of a factory-authorized service representative to start up units in accordance with manufacturer's written start-up instructions. Test controls and demonstrate compliance with requirements. Replace defective controls and equipment as required. Owner may elect to witness these tests. Provide a checklist/buyoff form for each unit which shall be signed by the unit manufacturer and Owner prior to the installer leaving the site. 1. Verify operation of remote panel, including pilot-light operation and failure modes. Inspect

the following: a. High-limit heat exchanger. b. Economizer to limited outside-air changeover. c. Alarms.

C. Operation and Maintenance Training: Provide the services of a manufacturer's service representative to instruct Owner's personnel in operation and maintenance of units. Training shall consist of a minimum of 80 hours of classroom and on-site instruction in 8 hour segments covering various shifts. Training shall include start-up and shutdown, servicing and preventative maintenance schedule and procedures, troubleshooting procedures, and procedures for obtaining repair parts and technical assistance. Review operation and maintenance data contained in the operation and maintenance manuals.

D. Provide on going maintenance as required in the Contract Work Scope and as identified on the following table.

E. Provide on going maintenance as required in the Contract Work Scope and as identified on the following table.

Chrysler LLC

PACKAGED, OUTDOOR, CENTRAL-STATION AIR-HANDLING UNITS 237413 – 15 of 19

Equipment Weekly Maintenance Monthly Maintenance 3-Month Maintenance 6-Month Maintenance 12-Month Maintenance

Supply Fan None None None

Grease Fan per Manf. Instructions Check Drive Belts for tightness and alignment

Grease fan per Manf. Instructions. Check drive belts for tightness and alignment

Motor None None None Grease per Manf. Instructions

Grease per Manf. Instructions

Primary Filters Change at 1" WC

Reader Valve None None None Raise plant pressure to valve calibrated pressure

Raise plant pressure to valve calibrated pressure

F & T Steam Trap None None None Remove plug at bottom and blow down

Remove plug at bottom and blow down

Pilot Regulator None None None Check for leaks, pulsating. Check for proper flow past regulator

Check for leaks, pulsating. Check for proper flow past regulator

Solenoid Valve None None Inspect, take out and clean if not working properly

Inspect, take out and clean if not working properly


Main Regulator None None None Check for leaks, pulsating check for proper flow pas regulator

Check for leaks, pulsating. Check for proper flow past regulator

Flow Regulator None None None Check for leaks. Check for proper GPM

Check for leaks. Check for proper GPM

Pressure Reducing Valve None None None Check for leaks. Check for proper setting. Adjust if necessary

Check for leaks. Check for proper setting. Adjust if necessary

Gate Valve None None None Check for leaks and proper seating

Check for leaks and proper seating

Chrysler LLC



Circuit Setter None None Check with circuit setter testes to proper flow

None None

Vacuum Breaker None None Inspect for proper operation

Inspect for proper operation

Remove cap and inspect seat for any debris

Solenoid Valve None None Inspect, take out and clean it not working properly



Safety, Blocking, Reset, and Staging Valves

None None None Check for leaks and valve seating. Cycle valves 10-15 times.

Check for leaks and valve seating. Cycle valves 10-15 times.

Control Valve None None None Check for leaks and proper seating. Cycle valve, adjust if necessary

Check for leaks and proper seating. Cycle valve, adjust if necessary

Coils None None None Check for leaks and airflow. Clean or comb fins if necessary

Check for leaks and airflow. Clean or comb fans if necessary

Butterfly Valve None None None Check for leaks, manually open and close to check seating and flow

Check for leaks, manually open and close to check seating and flow

Butterfly Valve None None None Check for leaks, manually open and close to check seating and flow

Check for leaks, manually open and close to check seating and flow

Air Vent None None None Check for leaks and proper operation

Check for leaks and proper operation

Check Valve None None None Check leaks, check for back flow

Check leaks, check for back flow

Globe Valve None None None Check for leaks and proper seating. Repack if necessary

Check for leaks and proper seating. Repack if necessary

Chrysler LLC



Burner (Maxon)

None None None

Check burner body and mixing plates for scale or foreign material. Clean or replace if necessary

Check burner body and mixing plates for scale or foreign material. Clean or replace if necessary

Intake Damper None None None Check blades for seating check for smooth operation. No binding

Check blades for seating. Check for smooth operation. No binding

Magnebelic Pressure Gauge

None None None Check zero adjustment. Check tips and fitting for tightness or blockage

Check zero adjustment. Check tips and fitting for tightness or blockage

Mist Eliminator None None None Check blades to see if in proper assembly. Clean if necessary

Check blades to see if in proper assembly. Clean if necessary

Steam Humidifier None None Check for proper distribution check that parts are not plugged

Check for proper distribution check that parts are not plugged

Check for proper distribution check that parts are not plugged

Thermometer None Check for operation None None None

Check Valve None None Check for proper flow and operation

Check for proper flow and operation

Check for proper flow and operation

Plug Valve None None None Check for leaks and proper seating

Check for leaks and proper seating

Low Gas Pressure Switch None None None

Adjust setpoint for normal operation check pressure switch for performance as intended

Adjust setpoint for normal operation. Check pressure switch for performance as intended.

Relief Valve None None Check for proper operation. Adjust pressure if necessary

Check for proper operation. Adjust pressure if necessary

Check for proper operation. Adjust pressure if necessary

Chrysler LLC



Humidifier None None

Check for proper water distribution. Clean holes in distribution header if needed. Check to make sure media is not clogged



Control Valve None None

Restriction and filter screens may require periodic cleaning, depending on quality of air used


Restriction and filter screens may require periodic cleaning, depending on quality of air used.

Control Valve None None



Restriction and filter screens may require periodic cleaning, depending on quality of air used.

Control Valve None None None Modulate 0% to 100% check for proper stroke

Modulate 0% to 100% check for proper stroke

Damper Operation None None None Check arms and linkages for tightness or binding adjust if necessary

Check arms and linkages for tightness or binding adjust if necessary

Pholehelic Pressure Switch None None None

Adjust setpoint for normal operation Check pressure switch for performance as intended

Adjust setpoint for normal operation. Check pressure switch for performance as intended

Damper Limit Switch None None None Check to see if switch makes. Adjust aim if necessary.

Check to see fi switch makes. Adjust aim if necessary.

Vortex Operator None None None Check arms and linkages for tightness or binding adjust if necessary

Check arms and linkages for tight or binding adjust if necessary

Gas Valve Operator None None None Check arms and linkages for tightness or binding adjust if necessary

Check arms and linkages for tightness or binding adjust fi necessary

Flame Sensor None None Clean viewing window and check for proper operation

Clean viewing window and check for proper operation

Clean viewing window and check for proper operation

Chrysler LLC



Heat Exchanger None None None Check for leaks and air flow. Clean and comb fans if necessary

Check for leaks and air flow. Clean and comb fans if necessary

Pump None None Observe pump and bearings for wear.

Observe pump and bearings for wear

Observe pump and bearings for wear.

Flow Meter None None None Check for leaks and proper flow. Clean if necessary

Check for leaks and proper flow. Clean if necessary

Float Valve None None None Check for proper operation. Adjust to performance as intended

Check for proper operation. Adjust to performance as intended

Strainer None None Blow-Down Blow-Down Blow-Down

Strainer None None Blow-Down Blow-Down Blow-Down

Temperature Switch None None None

Check for proper operation. Adjust to intended seating if necessary

Check for proper operation. Adjust to intended seating if necessary

END OF SECTION