HomeMy WebLinkAbout232424 GAS-FIRED MAKEUP AIR UNITS.pdfa
L’Acquis Number: 12056
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Matt the Miller's Tavern
Carmel, Indiana
Project No. 12056 GAS�FIRED MAKEUP AIR UNITS 23 74 23 � 1
SECTION 23 24 24
Gas�Fired Makeup Air Units
PART 1 � GENERAL
1.01 RELATED SECTIONS:
A. Drawings, general provisions of the Contract, including General and Supplementary
Conditions, and Division�1 Specification Sections and Division 20 Specification
Sections, apply to work of this Section.
1.02 SUBMITTALS:
A. Product Data: Submit manufacturer's technical product data and installation instructions
for gas�fired makeup air units.
B. Shop Drawings: Submit layout drawings of gas�fired makeup air units showing layout of
components. In addition, show details of installation and associated supporting
structures.
C. Wiring Diagrams: Submit wiring diagrams for gas�fired makeup air units showing
connection to electrical power feeders. Differentiate between portions of wiring that are
manufacturer�installed and portions to be field�installed.
D. Maintenance Data: Submit maintenance data and parts list for each gas fired makeup
unit, control, and accessory; including "trouble�shooting" maintenance guide. Include
this data, product data, shop drawings, and wiring diagrams in maintenance manual; in
accordance with requirements of Division 1.
1.03 QUALITY ASSURANCE:
A. Manufacturer's Qualifications: Firms regularly engaged in manufacture of units of types,
sizes and ratings required, whose products have been in satisfactory use in similar
service for not less than 5 years.
B. Codes and Standards:
1. Electrical, Code Compliance: Comply with applicable local electrical code
requirements of the authority having jurisdiction and NEC pertaining to
construction and installation of air handling units.
2. UL Compliance: Comply with applicable requirements of UL 1096, pertaining to
remote control panels for heating equipment, and UL 486A, "Wire Connectors
and Soldering Lugs for Use with Copper Conductors." Provide units and
components which are UL�listed and labeled.
3. Unit must meet Factory Mutual (FM) and Industrial Risk Insurers (IRI)
requirements.
PART 2 � PRODUCTS
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L’Acquis Number: 12056
____________________________________________________________________________________________
Matt the Miller's Tavern
Carmel, Indiana
Project No. 12056 GAS�FIRED MAKEUP AIR UNITS 23 74 23 � 2
2.01 MANUFACTURERS:
A. Manufacturers: Subject to compliance with requirements, provide units of one of the
following:
1. Gas�Fired make�up air unit shall be by Kitchen hood manufacturer.
2.02 GENERAL:
A. Provide roof�mounted, gas�fired, makeup air unit as indicated. Unit shall be factory
assembled, wired, and test fired. Units shall be suitable for roof curb mounting including
steel rails and lifting lugs.
2.03 CASING:
A. Unit casing shall be constructed of zinc coated, 14 gauge, galvanized steel. Exterior
surfaces shall be cleaned, phosphatized and finished with a baked enamel finish. Access
doors are to be hinge mounted with industrial type hardware for easy access to all
compartments including the motor, blower, burner, electrical components, and manifold
sections. All casings shall be air tight and weatherproof.
2.04 FANS:
A. Provide fan section with forward curved, double width, double inlet, centrifugal type
fans. Fans shall be tested in accordance with AMCA 210. Fans shall be provided with
spring type vibration isolation. Bearings shall be self�aligning, ball type with permanent
lubrication fittings. Provide extended grease lines for lubrication of all bearings from
outside of the unit. Provide access to motor, drive, and bearings through removable
casing panels. Provide fan shafts constructed of solid hot rolled steel, ground and
polished, with key�way, and protectively coated with lubricating oil. Provide cast iron or
steel pitched sheaves, dynamically balanced, bored to fit shafts and keyed, sized with a
capacity of 25% greater than the motor horsepower. Provide change out sheave and
belts, if necessary, for final balance. Provide one (1) spare set of belts. Fan motors shall
be energy efficient open drip�proof type with Class B insulation (three�phase). Factory
mount motor on slide rails for adjustment of belt(s) tension.
2.05 BURNER SECTION:
A. Burner section shall contain a burner constructed of rust resistant cast iron bodies which
serve as the gas manifold, drilled to discharge the fuel between diverging stainless steel
mixing plates. The entire burner assembly shall be mounted directly in the air stream
being heated. Air velocities across the burner assemblies shall be maintained by the use
of adjustable profile plates. The unit shall be provided with a wide range burner with a
modulating turndown ratio of 25 to 1. The operation of the burner shall be programmed
through the flame safeguard with timed pre�purge and flame sensing.
B. Gas train shall consist of a manual shutoff valve, motorized electric main gas valve,
modulating gas valve, manual pilot gas shutoff valve, manual pilot gas pressure
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L’Acquis Number: 12056
____________________________________________________________________________________________
Matt the Miller's Tavern
Carmel, Indiana
Project No. 12056 GAS�FIRED MAKEUP AIR UNITS 23 74 23 � 3
regulator, pilot gas valve, orifice needle valve, high/low gas pressure switch, two manual
auxiliary gas shutoff valves, normally open vent valve, and an auxiliary gas valve. Gas
train must meet Factory Mutual and Industrial Risk Insurers requirements.
2.06 CONTROLS:
A. Basic unit controls shall consist of a spark ignition system with flame rod sensing of
flame, high temperature limit switch, flame safeguard, ignition transformer, air proving
differential switch, and a modulating control system to maintain negative building
pressurization.
B. All controls shall be factory installed and wired including fan motor starter with external
overload protection, low voltage terminal strip, control transformers, fusible disconnect,
a 115V duplex receptacle, and a single point power connection point. Unit voltage shall
be 2080V/60HZ/3Ph. All wiring shall be color coded and within accordance with NEC.
A circuit diagram shall be provided within the unit. All components shall bear the U.L.
label.
2.07 INLET HOOD:
A. Provide inlet hood with bird screen constructed of 18 gauge galvanized steel. Bird
screen shall be 3/4” mesh at minimum.
2.08 ROOF CURBS:
A. Provide 18” high prefabricated 12�gauge galvanized steel roof curb designed and
manufactured by the unit manufacturer for field installation on roof decking. Neoprene
gasketing shall be provided, factory installed on the curb, to form a positive, weather
tight seal between the curb and unit. Design shall comply with all requirements with the
National Roof Curb Contractors Association.
PART 3 � EXECUTION
3.01 INSTALLATION OF UNITS:
A. General: Install rooftop heating and cooling units in accordance with manufacturer's
installation instructions. Install units plumb and level, firmly anchored in locations
indicated, and maintain manufacturer's recommended clearances. Install in accordance
with applicable portions of NEC, and with recognized industry practices to ensure that
units fulfill requirements.
B. Support: Install units on roof curb as described above, in accordance with National
Roofing Contractor's Association (NRCA) installation recommendations.
C. Coordinate with other work, including electrical wiring/cabling and ductwork as
necessary to interface installation of units with other work.
D. Clean dust and debris from each unit as it is installed to ensure cleanliness.
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L’Acquis Number: 12056
____________________________________________________________________________________________
Matt the Miller's Tavern
Carmel, Indiana
Project No. 12056 GAS�FIRED MAKEUP AIR UNITS 23 74 23 � 4
E. Touch up scratched or marred unit enclosure surfaces to match original finishes.
F. Tighten electrical connectors and terminals, including screws and bolts, in accordance
with equipment manufacturer's published torque tightening valves for equipment
connectors. Where manufacturer's torquing requirements are not indicated, tighten
connectors and terminals to comply with tightening torques specified in UL Standard
486A and B.
3.02 GROUNDING:
A. Provide equipment grounding connections for units as required. Tighten connections to
comply with tightening torques specified in UL Standard 486A to assure permanent and
effective grounding.
3.03 CHECK�TEST�START PROCEDURE:
A. The unit manufacturer shall provide a factory�trained service man to supervise the
evacuation, charging and start�up of the units for final operation.
B. The contractor shall provide all material (including refrigerant) and labor required to
evacuate, charge, and accomplish the check, test, and start procedure as recommended by
unit manufacturer.
C. The unit manufacturer's service man shall provide and complete the manufacturer's
check, test, and start forms. One copy shall be sent to the architect/engineer, one copy to
the manufacturer's factory, and one copy to the owner.
3.04 WARRANTY:
A. The contractor and unit manufacturer shall be responsible for the warranty failures on the
units for a period of one (1) year.
1. Unit manufacturer shall warrant all components to be free from defects and
failures and shall supply all parts required to correct warranty failures.
2. Mechanical contractor shall supply all labor, cartage, and supplies required to
replace failed parts.
END OF SECTION