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15780-1

SECTION 15780

PACKAGED ROOFTOP AIR HANDLING UNITS

PART 1 - GENERAL

1.1

1.2

1.3

DESCRIPTION

A.

Work Included: Furnish and install packaged cooling-only rooftop air handling units
(RTU) of the size and capacity as shown on the Drawings. Unit shall include
compressor, condenser coil, fans, motors, refrigerant reservoir, charging valve,
holding charge of R-410A, refrigeration specialties and integral control panel,
completely packaged, piped, wired and assembled suitable for outside installation.

QUALITY ASSURANCE

A.

mo

ARI Compliance:

1. Comply with ARI 210/240 and ARI 340/360 for testing and rating energy
efficiencies for air handling units.

2. Comply with ARI 270 for testing and rating sound performance for air handling
units.

ASHRAE Compliance:

1. Comply with ASHRAE 15 for refrigerant 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".

ASHRAE/IESNA 90.1 Compliance: Applicable requirements in ASHRAE/IESNA

90.1, Section 6 - "Heating, Ventilating, and Air-Conditioning."

UL Compliance: Comply with UL 1995.

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.

WARRANTY

A.

Special Warranty: Manufacturer's standard form in which manufacturer agrees to

replace components of RTU which fail in materials or workmanship within specified

warranty period.

1. Warranty Period for Compressors: Manufacturer's standard, but not less than
10 years from date of Substantial Completion.

2. Warranty Period for Control Boards: Manufacturer's standard, but not less than
three years from date of Substantial Completion.

PART 2 - PRODUCTS

2.1

PACKAGED HEAT PUMP TYPE AIR HANDLING UNIT
A. General: Manufacturer and model numbers are indicated to establish type and quality.
B. Acceptable Manufacturers:

l. Trane.
2. Carrier.

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15780-2
PACKAGED ROOFTOP AIR HANDLING UNITS

3. York.

4. Or approved equal.

General: The operating range shall be between 115°F and 0 °F in cooling as standard
from the factory for units with microprocessor controls. Cooling performance shall
be rated in accordance with ARI testing procedures. All units shall be factory
assembled, internally wired, fully charged with R-410A, and 100 percent run tested
to check cooling operation, fan and blower rotation, and control sequence before
leaving the factory. Wiring internal to the unit shall be colored and numbered for
simplified identification. Units shall be UL listed and labeled, classified in accordance
for Central Cooling Air Conditioners.

Casing: Unit casing shall be constructed of zinc coated, heavy gauge, and galvanized
steel. Exterior surfaces shall be cleaned, phosphatized, and finished with a weather-
resistant baked enamel finish. Unit's surface shall be tested 672 hours in a salt spray
test in compliance with ASTM B117. Cabinet construction shall allow for all
maintenance on one side of the unit. All exposed vertical panels and top covers in the
indoor air section shall be insulated with a cleanable foil-faced, fire-retardant
permanent, odorless glass fiber material. All insulation edges shall be either captured
or sealed. The unit's base pan shall have no penetrations within the perimeter of the
curb other than the raised 1.125 inch high downflow supply/return openings to
provide an added water integrity precaution, if the condensate drain backs up. The
base of the unit shall have provisions for forklift and crane lifting, with forklift
capabilities on three sides of the unit.

Unit Top: The top cover shall be one piece construction or, where seams exist, it shall
be double-hemmed and gasket-sealed.

Filters: 2-inch thick, throwaway filters.

Compressors: All units shall have direct-drive, hermetic, scroll type compressors with
centrifugal type oil pumps. Motor shall be suction gas-cooled and shall have a voltage
utilization range of plus or minus 10 percent of unit nameplate voltage. Internal
overloads shall be provided with the scroll compressors.

Refrigerant Circuits: Service pressure ports, and refrigerant line filter driers are
factory-installed as standard. An area shall be provided for replacement suction line
driers.

Evaporator and Condenser Coils: Internally finned copper tubes mechanically bonded
to a configured aluminum plate fin. Coils shall be leak tested at the factory to ensure
the pressure integrity. The evaporator coil and condenser coil shall be leak tested to
650 psig and pressure tested to 450 psig. Removable, reversible, double-sloped
condensate drain pan with through the base condensate drain.

Outdoor Fans: The outdoor fan shall be direct-drive, statically and dynamically
balanced, draw-through in the vertical discharge position. The fan motor shall be
permanently lubricated and shall have built-in thermal overload protection.

Indoor Fan: Indoor fan motor shall be belt drive type with FC fans with adjustable
sheaves. Motors shall be thermally protected.

Controls: Unit shall be completely factory-wired with necessary controls and
contactor pressure lugs or terminal block for power wiring. Unit shall provide an
external location for mounting a fused disconnect device. A choice of microprocessor
or electromechanical controls shall be available. A centralized Microprocessor shall

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2.2

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PACKAGED ROOFTOP AIR HANDLING UNITS

provide anti-short cycle timing and time delay between compressors.

Phase monitor: Phase monitor shall provide 100% protection for motors and
compressors against problems caused by phase loss, phase imbalance, and phase
reversal. The module shall automatically reset from a fault condition.

Accessories: Factory-mounted disconnect switch and GFCI duplex electrical service
outlet.

Roof Mounting Curb: May be supplied factory assembled or disassembled. Once the
mounting curb is set in position, it shall be secured together with 1/4-20 x 1/2" long
sheet metal screw. The mounting curb shall have duct flanges shipped with it and no
separate duct flanges need be purchased.

PACKAGED VAV COOLING AIR HANDLING UNIT

A.
B.

Qn

General: Manufacturer and model numbers are indicated to establish type and quality.
Acceptable Manufacturers:

1. Trane.
2. Carrier.
3. York.

4. Or approved equal.

General: The units shall be dedicated downflow or horizontal airflow. The operating
range shall be between 115F and OF in cooling as standard from the factory for all
units Cooling performance shall be rated in accordance with AHRI testing
procedures. All units shall be factory assembled, internally wired, fully charged with
R-410A, and 100 percent run tested to check cooling operation, fan and blower
rotation and control sequence, before leaving the factory. Wiring internal to the unit
shall be colored and numbered for simplified identification. Units shall be UL listed
and labeled.

Casing: Unit casing shall be constructed of zinc coated, heavy gauge, galvanized steel.
Exterior surfaces shall be cleaned, phosphatized, and finished with a weather-resistant
baked enamel finish. Unit's surface shall be tested 672 hours in a salt spray ted in
compliance with ASTM B117. Cabinet construction shall allow for all maintenance
on one side of the unit. In order to ensure a water and airtight seal, service panels shall
have lifting handles and no more than three screws to remove. All exposed vertical
panels and top covers in the indoor air section shall be insulated with a 0.5 inch, 1
pound density foil-faced, fire-resistant, permanent, odorless, glass fiber material. The
base of the downflow unit shall be insulated with 0.5 inch, 1 pound density foil-faced,
closed-cell material. The downflow unit's base pan shall have no penetrations within
the perimeter of the curb other than the raised 1.125 inch high supply/return openings
to provide an added water integrity precaution, if the condensate drain back up. The
base of the unit shall have provisions for forklift and crane lifting.

Unit Top: The top cover shall be one piece, or where seams exist, double hemmed
and gasket sealed to prevent water leakage.

Filters: 2-inch pleated media filters.

Compressors: All units shall have direct-drive, hermetic, scroll type compressors with
centrifugal type oil pumps. Motor shall be suction gas-cooled and shall have a voltage
utilization range of plus or minus 10 percent of nameplate voltage. Internal overloads
shall be provided with the scroll compressors. Unit shall have crankcase heaters,
phase monitors and low and high pressure control.

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PACKAGED ROOFTOP AIR HANDLING UNITS

Refrigerant Circuits: Each refrigerant circuit shall have independent fixed orifice or
thermostatic expansion devices, service pressure ports, and refrigerant line filter
driers factory installed. An area shall be provided for replacement suction line driers.
Evaporator and Condenser Coils: Microchannel coils shall be burst tested by the
manufacturer. Internally finned copper tubes mechanically bonded to a configured
aluminum plate fin shall be standard for evaporator coils Microchannel condenser
coils shall be standard on all units. Coils shall be leak tested to ensure the pressure
integrity. The evaporator coil and condenser coil shall be leak tested to 225 psig and
pressure tested to 450 psig. Sloped condensate drain pans shall be standard.

Outdoor Fans: The outdoor fan shall be direct-drive, statically and dynamically
balanced, draw-through in the vertical discharge position. The fan motors shall be
permanently lubricated and shall have built-in thermal overload protection.

Indoor Fan: Belt driven, FC centrifugal fans with adjustable motor sheaves. Units
shall have an adjustable idler-arm assembly for quick-adjustment of fan belts and
motor sheaves. All motors shall be thermally protected.

Controls: Unit shall be completely factory-wired with necessary controls and
contactor pressure lugs or terminal block for power wiring. Unit shall provide an
external location for mounting a fused disconnect device. A choice of microprocessor
or electromechanical controls shall be available. A centralized Microprocessor shall
provide anti-short cycle timing and time delay between compressors.

VAV Operation: The VFD shall receive a 0-10 Vde signal from the unit controls
based upon supply static pressure and shall cause the drive to accelerate or decelerate
as required to maintain the supply static pressure setpoint. When subjected to high
ambient return conditions the VFD shall reduce its output frequency to maintain
operation.

Roof Mounting Curb: May be supplied factory assembled or disassembled. Once the
mounting curb is set in position, it shall be secured together with 1/4-20 x 1/2" long
sheet metal screw. The mounting curb shall have duct flanges shipped with it and no
separate duct flanges need be purchased.

PART 3 - EXECUTION

3.1 INSTALLATION

A.

B.

Install the packaged unit in strict accordance with the manufacturer's instructions and

recommendations and as shown on the Drawings.

Roof Curb: Install unit level on structural curb. Coordinate roof penetrations and

flashing with roof construction. Secure unit to upper curb rail, and secure curb base

to roof framing with anchor bolts.

Install condensate drain, minimum connection size, with trap and indirect connection

to nearest roof drain or area drain.

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 terminate at flexible connection.

2. Apply 2-inch thick blanket-type fiberglass insulation at ductwork connection
between RTU and ductwork.

Connect supply and return ducts to RTU with flexible duct connectors specified in

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PACKAGED ROOFTOP AIR HANDLING UNITS

Division 15 Section "Duct Accessories."

3.2 FIELD QUALITY CONTROL

A.

B.
C.

Manufacturer's Field Service: Inspect, test, and adjust components, assemblies, and

equipment installations, including connections. Report results in writing.

Perform tests and inspections and prepare test reports.

Manufacturer's Field Service: Inspect components, assemblies, and equipment

installations, including connections, and to assist in testing. Report results in writing.

Tests and Inspections:

1. After installing RTU and after electrical circuitry has been energized, test unit
for compliance with requirements.

2. — Inspect for and remove shipping bolts, blocks, and tie-down straps.

3. Operational Test: After electrical circuitry has been energized, start unit to
confirm proper motor rotation and unit operation.

4. Test and adjust controls and safeties. Replace damaged and malfunctioning
controls and equipment.

5. Remove and replace malfunctioning equipment and retest as specified above.

3.3 CLEANING AND ADJUSTING

A.

Occupancy Adjustments: When requested within 12 months of date of Substantial
Completion, provide on-site assistance in adjusting system to suit actual occupied
conditions. Provide up to two visits to site during other-than-normal occupancy hours
for this purpose.

After completing system installation and testing, adjusting, and balancing RTU and
air-distribution systems, clean filter housings and install new filters.

END OF SECTION

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15815-1

SECTION 15815

AIR TERMINAL BOXES

PART 1 - GENERAL

1.1 DESCRIPTION
A. Work Included: Provide and install air terminal boxes of types, sizes and
configuration as shown on the Drawings and specified herein.
B. Related Work Specified Elsewhere: "HVAC - General" is specified in this Division.
"Electrical - General" is specified in Section 16000. For control sequence, refer to
Section 15609, “HVAC Instrumentation and Control (DDC).

12 QUALITY ASSURANCE
A. Verification of Capacity: Supply manufacturer's certificate of output for the unit.
B. Install equipment in compliance with International Mechanical Code, 2012 edition.
C. Provide air terminal units with performance characteristics matching scheduled
values, as a minimum, in conformance with the Massachusetts Energy Code
provisions of the Commonwealth of Massachusetts Building Code 780 CMR.

1.3 SUBMITTALS TO THE ENGINEER
A. Submit shop drawings, manufacturer's literature, installation instructions,
maintenance data and operating instructions as specified in the General Conditions
of the Construction Contract.

14 DELIVERY, STORAGE AND HANDLING
A. Deliver in manufacturer's unopened containers as job progress requires.
B. Storage: Store in unopened containers in a weathertight building.
C. Handling: Exercise care when handling heaters to prevent damage of any nature.

PART 2 - PRODUCTS

2.1 VARIABLE AIR VOLUME (VAV) BOXES
A. General: Manufacturer and model numbers are indicated to establish type and

quality.
B. Acceptable Manufacturers:
1. Price
2. __Enviro-Tec
3. Trane
4. Or equivalent product

2.2 MATERIALS
A. General: Factory built, pressure independent units, automatically adjustable air flow
rate, suitable for single duct applications. Use of dual-duct air terminal units is not
permitted. Clearly show on each unit the unit number air volumes corresponding to
the contract drawings. Coordinate flow controller sequence and damper operation
details with the drawings and Section 15604, "Automatic Temperature Control

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AIR TERMINAL BOXES

(Electric)". All air terminal units shall be brand new products of the same

manufacturer.

B. Capacity and Performance: The maximum capacity of a single terminal unit shall
not exceed the capacity as indicated on the mechanical schedule.

C. Sound Power Levels: Acoustic performance of the air terminal units shall not
exceed levels as indicated on the mechanical schedule.

D. Casing: Unit casing shall be constructed of galvanized steel no lighter than 22
gauge. Assembled with longitudinal lock seam construction. Provide hanger
brackets for attachment of supports.

1. | Fiber-Free Foam Insulation: Complying with UL 181 erosion, mold growth
and humidity requirements in accordance with ASHRAE Std. 62.1, and
having a maximum flame/smoke spread of 25/50 for both the insulation and
the adhesive, when tested in accordance with ASTM E84. Secure insulation
with adhesive. 1 inch thick, R-value of 4.0.

2. Access panels (or doors): Provide panels large enough for inspection,
adjustment and maintenance without disconnecting ducts, even if there are no
moving parts. Panels shall be insulated to same standards as the rest of the
casing and shall be secured and gasketed airtight. It shall require no tool other
than a screwdriver or socket wrench to remove.

3. Total leakage from casing: Not to exceed 2 percent of the nominal capacity of
the unit when subjected to a static pressure of 3 inch WG, with all outlets
sealed shut and inlets fully open.

E. Construct dampers and other internal devices of corrosion resisting materials which
do not require lubrication or other periodic maintenance.

1. Damper Leakage: Not greater than 2 percent of maximum rated capacity,
when closed against inlet static pressure of 4 inch WG.

F. Provide multi-point velocity pressure sensors with external pressure taps.

1. Provide direct reading air flow rate table pasted to box.

G. Provide static pressure tubes.

H. Factory furnished and installed, externally powered, standalone digital variable air
volume controller and damper actuator.

PART 3 - EXECUTION

3.1 INSTALLATION
A. Install in strict accordance with the manufacturer's instructions and
recommendations and as shown on the Drawings.
B. Install in accordance with manufacturer's instructions and recommendations.

3.2 ADJUSTING
A. Balance air terminal unit to provide scheduled airflow at maximum operating
efficiency in accordance with specification section 15907, "Testing, Adjusting and
Balancing". Submit a report indicating the results to the Engineer for review.

END OF SECTION

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City of Nashua

Purchasing Department

Administrative Services Division
229 Main Street - Nashua, NH 03060

(603) 589-3330
Fax (603) 594-3233

March 9, 2022
Memo #22-248

TO: Mayor Donchess
Finance Committee

SUBJECT: Landscaping for the Riverfront in the amount not to exceed $180,000 funded from 54280
Building/Grounds Maintenance/Riverfront TIF Fund

Please see attached communications from Tim Cummings, Director of Economic Development, dated
March 8, 2022 for project specific details related to this purchase. Below please find a summary of the
purchase approval request:

Item:

Value:
Vendor:
Department:
Source Fund:

Ordinance:

2022 Landscaping: seasonal maintenance at the Library to Pan Am Pedestrian
Bridge, Peddlers to Margaritas, upper edge of BAE parking lot, and both sides of

river behind 53-59 Main Street to Cottonmill Bridge
$30,000 per month for May thru October 2022 to total $180,000

Doty Group

183 Economic Development

54280 Building/Grounds Maintenance/ Riverfront TIF Fund

Pursuant to § 5-78 Major purchases (greater than $25,000) A. All supplies and
contractual services, except as otherwise provided herein, when the estimated
cost thereof shall exceed $25,000 shall be purchased by formal, written contract

from the lowest responsible bidder, after due notice inviting bids.

A competitive bidding RFP for this project was issued on 4/27/2021 and the following bids were received:

Vendor

Location

Amount

Note

Doty Group

Hollis NH

$376,00

The Economic Development Division, and the Purchasing Department respectfully request your approval

of this contract.

Regards,
Kelly Parkinson

Purchasing Manager

Ce: T Cummings
C Lindner

15820-1

SECTION 15820

VENTILATION FANS

PART 1 - GENERAL

1.1 DESCRIPTION
A. Work Included: Provide and install ventilation fans of the types and arrangement as
shown on the Drawings and as specified herein.
B. Related Work Specified Elsewhere "HVAC - General" is specified in this Division.
"Electrical-General" is specified in Section 16010.

1.2 QUALITY ASSURANCE
A. Standards

1.

Air Movement and Control Association

AMCA 210-85 Laboratory Methods of Testing Fans for Rating
AMCA 300-85 Test Code for Sound Rating

National Fire Protection Association

NFPA 70-90 National Electrical Code

NFPA 90A Installation of Air Conditioning and Ventilating Systems

B. Each fan shall be licensed by AMCA to bear the Certified Rating Seal. When this
standard is not applicable, the manufacturer shall submit data to verify the fan
capacity at the specified operating condition.

1.3 SUBMITTALS
A. General: Submittals shall be in accordance with specification Section 01340.
B. Submittals shall show physical dimensions, shaft sizes, drives, drive arrangement,
motor data, electrical data and performance curves.

PART 2 - PRODUCTS

2.1 MATERIALS
A. General: Refer to the Drawings for the following information (when applicable):

B.

2.
3.
4.
5.
M.

Specific type and size of fan.

otors:

Electrical characteristics - voltage and phase.

Direct or belt drive.

Special corrosion resistant coatings.

Additional accessories and specialties.

Totally enclosed fan cooled (TEFC) unless noted otherwise.

Integral thermal overload protection on single phase fractional horsepower
motors

ECM motors shall be DC electronic commutation type motor (ECM)

specifically designed for fan applications. Internal motor circuitry to convert
AC power supplied to the fan to DC power to operate the motor. Motor shall
be speed controllable down to 20% of full speed (80% turndown). Speed shall

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VENTILATION FANS

be controlled by either a potentiometer dial mounted at the motor or by a 0-10
VDC signal.

C. Roof Curbs:

l.
2.
3.
4.

5.

6.

Required for all roof mounted fans unless an integral part of roof structure and
so shown on the Architectural Drawings.

18 inches high.

Supplied with fan.

Prefabricated all welded aluminum construction structurally reinforced to
support fan.

1% inch thick rigid fiberglass insulation.

Wood blocking when required for fan installation.

D. Inline Centrifugal Fans:

1.

wWPwWn

6.

7.

Acceptable Manufacturers

a. Greenheck Fan Corp.

b. Loren Cook, Co.

c. Pennbarry

d. Or approved equal.

Duct mounted, belt or direct driven as scheduled.

Fan wheels, aluminum backward inclined.

Housing, all aluminum construction.

Mounting brackets and vibration isolations required for wall mounting or
hanging from ceiling as shown.

AMCA certified for both air and sound performance.

Completely wired internally with leads brought to an external junction box.

E. Power Roof Ventilators; Upblast Type:

l.

6.

7.

Acceptable Manufacturers:

a. Greenheck Fan Corp.

b. Loren Cook, Co.

c. Pennbarry

d. Or approved equal.

Ventilator housings: Spun aluminum construction completely weatherproofed
and securely seated on and fastened to the roof curb.

Hood shall be designed with necessary wind bands, and venturi inlet to
provide a vertical upward discharge pattern.

Fan Wheels: Aluminum Centrifugal, backward inclined, non-overloading,
quiet-operating, statically and dynamically balanced.

Unit shall include motor and drive assembly cooling tube, and drainage area
with drain plug.

Gravity backdraft damper unless motorized damper is required and shown on
the Drawings.

Aluminum bird screen.

PART 3 - EXECUTION

3.1 INSTALLATION
A. Install as required in strict accordance with the manufacturer's instructions and
recommendations and as shown on the Drawings.

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