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15619-1

SECTION 15619

GAS FIRED SEPARATED COMBUSTION AIR HANDLING UNITS

PART 1 - GENERAL

1.1 DESCRIPTION

A. Work Included: Provide and install pad-mounted natural gas fired, separated
combustion makeup air unit of the type, size and performance 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 gas piping, refer to Section
15444, "Natural Gas System". For control sequence, refer to Section 15604,
"Automatic Temperature Control (Electric)".

12 QUALITY ASSURANCE
A. Verification of Capacity: Supply manufacturer's certificate of output for the unit.
B. Install unit in compliance with NFPA 54 as amended by the State of New Hampshire
"Propane and Natural Gas Equipment Standards".
C. Provide air handling units with performance characteristics matching scheduled
values, as a minimum, in conformance with ASHRAE 90.1.

1.3 SUBMITTALS TO THE ENGINEER
A. Submit certificates, in duplicate, of verification of unit output and certification of
compliance with the American Gas Association Safety Standards.
B. 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 SEPARATED GAS-FIRED AIR HANDLING UNIT
A. General: Manufacturer and model numbers are indicated to establish type and quality.
B. Acceptable Manufacturers:
1. | Greenheck
2. Reznor
3. Equivalent product.

2.2 MATERIALS
A. Unit with Integral Indirect Gas-Fired Heating shall be fully assembled at the factory
and consist of an insulated metal cabinet, outdoor air intake with aluminum bird
screen, motorized intake damper, filter assembly for intake air, sensors, supply air

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blower assembly, and electrical control unit with all specified components and
internal accessories factory installed and tested and prepared for single-point high
voltage connection.

2.3 CABINET

A. Materials: Formed, double wall insulated metal cabinet, fabricated to permit access
to internal components for maintenance.

1. Outside casing: 18 gauge, galvanized steel meeting ASTM A653 for
components that do not receive a painted finish. Pre-painted components as
supplied by the factory shall have polyester urethane paint on 18 gauge
galvanized steel. Base rail is 12 gauge, galvanized steel.

2. Internal Assemblies: 24 gauge galvanized steel except for motor supports which
shall be minimum 14 gauge galvanized steel.

B. Comply with NFPA 90A and NFPA 90B and erosion requirements of UL 181.

1. Materials: Fiberglass insulation. If insulation other than fiberglass is used, it
must also meet the Fire Hazard Classification shown below.

a. Thickness: 1 inch

b. Fire Hazard Classification: Maximum flame spread of 25 and smoke
developed of 50, when tested in accordance with ASTM C 411.

c. Location and application: Floor of each unit shall be insulated with either
one half inch thick or 1 inch thick rigid fiberglass insulation, covered on
one surface with integral aluminum foil.

C. Access panels: Unit shall be equipped with removable access panels to provide easy
access to all major components. Access panels shall be fabricated of 18 gauge steel.
Removable access panels shall incorporate a formed drip edge.

D. Supply Air blower assembly: Blower assembly consists of an electric motor and a
belt driven, double width, double inlet forward curve blower. Assembly shall be
mounted on heavy gauge galvanized rails and further mounted on minimum 1.125
inch thick neoprene vibration isolators.

E. Control panel / connections: Unit shall have an electrical control center where all high
and low voltage connections are made. Control center shall be constructed to permit
single-point high voltage power supply connections.

F. Indirect Gas-Fired Furnace:

1. Integral combustion gas blower.

2. Fault sensors to provide fault conditions to optional digital controller or
building controls.

3. 4-pass tubular heat exchangers, constructed of type 409 stainless steel. Heat
exchanger tubes shall be installed on the vest plate by means of swaged
assembly, welded connections are not acceptable. Heat exchanger tubes shall
be supported by a minimum of two fabricated assemblies that support the tubes
and also permit expansion and contraction of the tubes.

4. Weather-tight metal housing with intake air vents.

5. | Hinged door shall provide access to the enclosed vest plate, control circuitry,
gas train, burner assembly and exhaust blower.

6. Shall include a kit for outdoor mounting with vertical stack venting.

G. Dampers: Motorized intake air dampers of low leakage type shall be factory installed.

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2.4 BLOWER

A. Supply Air: Belt drive motor and blower shall be assembled onto a minimum 14 gauge
galvanized steel platform and must have neoprene vibration isolation devices,
minimum of 1 - 1/8 inches thick.

B. Blower assemblies: Shall be statically and dynamically balanced and designed for
continuous operation at maximum rated fan speed and horsepower.

C. Centrifugal blower housing: Formed and reinforced steel panels to make curved scroll
housing with shaped cutoff.

D. Forward curved blower (fan) wheels: Galvanized or aluminum construction with inlet
flange and shallow blades curved forward in direction of airflow. Mechanically
attached to shaft with set screws.

E. Blower section motor source quality control: Blower performance shall be factory
tested for flow rate, pressure, power, air density, rotation speed and efficiency.
Ratings are to be established in accordance with AMCA 210, "Laboratory Methods
of Testing Fans for Rating".

2.5 MOTORS

A. General: Blower motors greater than .75 horsepower shall be "NEMA Premium"
unless otherwise indicated. Compliance with EPAct minimum energy-efficiency
standards for single speed ODP and TE enclosures is not acceptable. Motors shall be
heavy-duty, permanently lubricated type to match the fan load and furnished at the
specified voltage, phase and enclosure. Drives shall be sized for a minimum of 150%
of driven horsepower and pulleys shall be fully machined cast-type, keyed and fully
secured to the fan wheel and motor shafts. Electric motors of ten horsepower or less
shall be supplied with an adjustable drive pulley.

2.6 UNIT CONTROLS
A. The unit shall be constructed so that it can function as a stand-alone heating system
controlled by factory-supplied controllers, thermostats and sensors or it can be
operated as a heating system controlled by a Building Management System (BMS).
B. Sensors to be provided with the unit include:
1. Heating inlet air sensor
2. 120V/24V smoke detector

2.7 FILTERS
A. Unit shall have 2" thick permanent metal filters located in the outdoor air intake and
shall be accessible from the exterior of the unit.

PART 3 - EXECUTION

3.1 INSTALLATION
A. Install packaged unit in strict accordance with the manufacturer's instructions and
recommendations and as shown on the Drawings.
B. Install wind and seismic restraints according to manufacturer's written instructions
and in accordance with Division 15 Section "Vibration and Seismic Controls for
HVAC Piping and Equipment."

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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 and after electrical circuitry has been energized, test units 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 units 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 unit and
air-distribution systems, clean filter housings and install new filters.

END OF SECTION

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15626-1

SECTION 15626

HVAC SYSTEM PUMPS (IN-LINE CIRCULATORS)

PART 1 - GENERAL

1.1 DESCRIPTION
A. Work Included: Provide and install horizontal inline centrifugal single stage pumps
with the capacities and characteristics as shown on the equipment schedules.
B. Related Work Specified Elsewhere: "HVAC - General" is specified in this Division.

12 QUALITY ASSURANCE

A. Verification of Unit Output: Equipment shall be supplied with manufacturer's
certificate and pump curve for rated performance, horsepower, etc.

B. Acceptable Manufacturers:
1. Grundfos
2. Taco
3. Aurora
4. __ Bell and Gossett Company

PART 2 - PRODUCTS

2.1 MATERIALS
A. All pump casings shall be centerline discharge of cast iron designed for line mounting.
All pumps are to be provided with companion flanges. Units shall have a maximum
operating pressure of 175psig at a maximum operating temperature of 300° F.
B. Pumps shall have a cast bronze impeller and shall be dynamically balanced. Suction
and discharge flanges shall be provided with drilled and tapped gauge ports.
Pump shall be canned-rotor type, the pump and motor form an integral unit without
shaft seal and with only two gaskets for sealing. The bearings are lubricated by the
pumped liquid.
Controller shall be integrated in the control box.
Pump shall contain built-in differential-pressure and temperature sensor.
Rotor can shall be made of carbon-fiber-reinforced composite.
Stainless-steel bearing plate and rotor cladding.
Aluminium alloy stator housing.
Air-cooled power electronics.

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PART 3 - EXECUTION

3.1 INSTALLATION
A. Install using manufacturer's recommendations and as shown on the Drawings.
B. Install so no vibration is transmitted to piping system. Provide independent support
and flexible connections as required to eliminate pipeline vibration.
C. Fully lubricate pump in accordance with manufacturer's recommendations prior to
start-up.

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3.2 ADJUSTING
A. Test and run complete heating system under actual working conditions and adjust the
unit to the satisfaction of the Engineer.

END OF SECTION

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15671-1

SECTION 15671

DUCTLESS SPLIT SYSTEM HEAT PUMP UNITS

PART 1 - GENERAL

1.1 DESCRIPTION
A. Work Included: Furnish and install ductless split system heat pump systems of the
size and capacities as shown on the drawings. Each unit shall include an outdoor
condensing unit, high wall mounted direct expansion fan coil unit, refrigeration
specialties, refrigerant charge and wired remote control.
B. Related Work Specified Elsewhere.
1. "HVAC - General" is specified in this Division.

12 QUALITY ASSURANCE
A. Each system shall be rated and certified in accordance with ARI Standards 210/240
and 270. Components shall be listed in the ARI directory as matched sets (systems).
B. Unit construction shall comply with ANSI/ASHRAE 15, latest revision, the NEC and
be constructed in accordance with UL standards and shall carry the UL label of
approval.

PART 2 - PRODUCTS

2.1 MATERIALS
A. Condensing Unit
1. Unit Cabinet:

a. The casing shall be constructed from galvanized steel plate, finished with
an electrostatically applied, thermally fused acrylic or polyester powder
coating for corrosion protection and have a Munsell 3Y 7.8/1.1 finish.

b. Mounting feet shall be provided and shall be welded to the base of the
cabinet and be of sufficient size to afford reliable equipment mount and
stability.

c. Easy access shall be afforded to all serviceable parts by means of
removable panel sections.

d. The fan grill shall be of ABS plastic.

2. Fans:

a. The fan blades shall be of aerodynamic design for quiet operation, and the
fan motor bearings shall be permanently lubricated.

b. Theunit shall have horizontal discharge airflow. The fan shall be mounted
in front of the coil, pulling air across it from the rear and dispelling it
through the front. The fan shall be provided with a raised guard to prevent
external contact with moving parts

3. | Compressor:

a. The compressor shall be a DC twin-rotor rotary compressor with variable

speed inverter drive.

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b. The compressor shall be driven by inverter circuit to control compressor
speed. The compressor speed shall dynamically vary to match the room
load for significantly increasing the efficiency of the system which shall
result in significant energy savings.

c. The unit shall have an accumulator and high pressure safety switch.

d. The compressor shall be mounted to avoid the transmission of vibration.

Outdoor Coil:

a. The condenser coil shall be of copper tubing with flat aluminum. The coil
shall be protected with an integral metal guard.

Refrigerant Components:

a. Refrigerant circuit components shall include brass external liquid line
service valve with service gauge port connections, suction line service
valve with service gage connection port, service gage port connections on
compressor suction and discharge lines with Schrader type fittings with
brass caps, accumulator, reversing valve.

b. All refrigerant lines between outdoor and indoor units shall be of annealed,
refrigeration grade copper tubing, ARC Type, meeting ASTM B280
requirements, individually insulated in twin-tube, flexible, closed-cell,
CFC-free (ozone depletion potential of zero), elastomeric material for the
insulation of refrigerant pipes and tubes with thermal conductivity equal
to or better than 0.27 BTU-inch/hour per sqft / °F, a water vapor
transmission equal to or better than 0.08 Perm-inch and superior fire
ratings such that insulation will not contribute significantly to fire and up
to 1" thick insulation shall have a Flame-Spread Index of less than 25 and
a Smoke-development Index of less than 50 as tested by ASTM E 84 and
CAN / ULC S-102.

Safeties:

Operating safeties shall be factory selected, assembled, and tested. The

minimum functions shall include the following:

a. Compressor discharge over temperature protection.

b. System low voltage protection.

c. Compressor overload protection.

d. Compressor over current protection.

e. IPM module protection.

Electrical Requirements:

a. Power for the indoor unit shall be supplied from the outdoor unit.

b. Unit electrical power shall be a single point connection.

c. All power and control wiring must be installed per NEC and all local
electrical codes.

d. Units shall have high and low-voltage terminal block connections.

BB. Fan Coil Unit

l.

Unit Cabinet:

The cabinet shall be formed from high strength molded plastic with smooth
finish, flat front panel design with access for filter. Cabinet color shall be white
- Munsell 1.0Y 9.2/0.2. The unit shall be wall mounted by means of a factory
supplied, pre-drilled, mounting plate.

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Fans:

a. The unit fan shall be high performance, double inlet, forward curve, direct
drive sirocco fan with a single motor. The fans shall be statically and
dynamically balanced and run on a motor with permanently lubricated
bearings. The indoor fan shall consist of three (3) speeds: Low, Mid, and
Hi and Auto. The fan shall have a selectable Auto fan setting that will
adjust the fan speed based on the difference between controller set-point
and space temperature.

b. There shall be a motorized horizontal vane to automatically direct air flow
in a horizontal and downward direction for uniform air distribution. The
horizontal vane shall significantly decrease downward air resistance for
lower sound levels, and shall close the outlet port when operation is
stopped. There shall also be a set of vertical vanes to provide horizontal
swing airflow movement.

Coil:
The evaporator coil shall be of nonferrous construction with pre-coated
aluminum strake fins on copper tubing. The multi-angled heat exchanger shall
have a modified fin shape that reduces air resistance for a smoother, quieter
airflow. All tube joints shall be brazed with PhosCopper or silver alloy. The
coils shall be pressure tested at the factory. A condensate pan and drain shall
be provided under the coil. A drain pan level switch, designed to connect to the
control board, shall be provided and installed on the condensate pan to prevent
condensate from overflowing.
Controls:
The control system shall consist of a minimum of two (2) microprocessors, one
on each indoor and outdoor unit, interconnected by a single non-polar two-wire
cable. The microprocessor located in the indoor unit shall have the capability
of monitoring return air temperature and indoor coil temperature, receiving and
processing commands from a wireless or wired controller, providing emergency
operation and controlling the outdoor unit. The control signal between the
indoor and outdoor unit shall be pulse signal 24 volts DC. Indoor units shall
have the ability to control supplemental heat via 12 VDC output.

The unit shall have the following functions as a minimum:

a. Automatic restart after power failure at the same operating conditions as
at failure.

b. A timer function to provide a minimum 24-hour timer cycle for system
Auto Start/Stop.

c. Temperature sensing control to enter set points and operating conditions.

d. Automatic air sweep control to provide on or off activation of air sweep
louvers.

e. Dehumidification mode shall provide increased latent removal capability
by modulating system operation and set point temperature.

f. Fan-only operation to provide room air circulation when no cooling is
required.

g. Diagnostics shall provide continuous checks of unit operation and warn of
possible malfunctions. Error messages shall be displayed at the unit.

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h. Fan speed controls shall be user-selectable: high, medium, low or
microprocessor controlled automatic operation during all operating
modes.

The unit shall be protected against the following:

i. Indoor coil freeze-up.

j. Indoor coil high temperature protection shall be provided to detect
excessive indoor discharge temperature when unit is in heat pump mode.

5. Filters:
Units shall have filter rack with factory-supplied washable filter.
C. Systems shall be:

1. Mitsubishi
2. Daitkin
3. Or equal

PART 3 - EXECUTION

3.1 INSTALLATION
A. All system components shall be installed in strict accordance with the manufacturer’ s
instructions, recommendations and as shown on the Drawings.

3.2 STARTUP, TESTING, AND TRAINING
A. Provide startup, testing and training in accordance with the requirements of Section
01800.

END OF SECTION

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