J.3 Specifications (235416. & 236200).pdf

USDA FOREST SERVICE PROJECT SPECIFICATIONS

GAS-FIRED FURNACES

LNF HVAC Replacement 04/19

235416-1

SECTION 235416 - GAS-FIRED FURNACES

PART 1 - GENERAL

1.1 SECTION REQUIREMENTS

A. Submittals:

1. See Section C-4 SUBMITTALS/APPROVALS.

2. Product Data: For each type of product.

3. Documentation indicating that units comply with ASHRAE 62.1, Section 5 - "Systems and Equipment."

4. For solvent cements and adhesive primers, documentation including printed statement of

VOC content.

B. Warranties: Submit a written warranty executed by manufacturer agreeing to repair or replace furnaces that fail in materials or workmanship within 10 years from date of Substantial Completion.

1.2 QUALITY ASSURANCE

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

B. Comply with NFPA 70.

PART 2 - PRODUCTS

2.1 ASSEMBLY DESCRIPTION

A. General Requirements for Gas-Fired Furnaces: Factory assembled, piped, wired, and tested;

complying with ANSI Z21.47/CSA 2.3 and NFPA 54.

2.2 GAS-FIRED FURNACES

A. Furnaces shall be Energy Star qualified and use propane (LPG) gas fuel. Convert units to use propane gas if necessary.

B. The values listed for the furnaces in the line items under Section C1 - Description of Work are sea level values and shall be corrected for altitude. Furnaces shall be shipped completely factory assembled with all controls installed. Supply with intake & exhaust muffler and LPG conversion kit. The furnaces shall be similar to the original unit specifications that it is replacing and shall be able to operate with the existing HVAC ductwork system.

235416-2

C. Factory assembled, piped, wired, and tested; complying with ANSI Z21.47/CSA 2.3 and

NFPA 54.

1. Type of Gas: Propane. Convert unit to use propane gas if necessary.

2. Fan Motor: Fan blower motor shall be quiet, variable speed, direct drive, statically and dynamically balanced. Motor shall be multiple-speed and resiliently mounted. Change in blower speed shall be accomplished by a wiring change. Blower housing shall have a baked-on enamel finish.

3. Ignition: Pilot ignition shall be fully automatic and shall be with a solid-state electronic spark igniter.

4. Heat Exchanger: Aluminized steel.

5. Venting: The existing vents may be reused if it meets the manufacturer’s requirements.

If not, then the Contractor shall provide and install a new vent. A vent passing through the roof shall extend through the roof flashing, roof jack, or roof thimble. Vent shall be properly flashed to be leak free.

6. Burner Controls: Thermocouple sensor, flame rollout switch, vent safety shutoff sensor, and limit control. Main burners and pilot are extinguished during the off cycle.

7. Automatic Controls: Solid-state board to delay fan start and shutdown. Controls shall be compatible to existing HVAC control system. Shall have gas controls which provide 100% safety shut off, and 24 volt redundant combination gas control valve which combines automatic safety pilot, pilot filtration, manual set knob (on-off), automatic electric valve (dual) and gas pressure regulation. Fan and limit controls shall be factory installed and give protection against abnormal operating condition and control blower operation.

8. Configuration: Upflow and Horizontal. Match existing unit configurations.

9. Heating Capacity: Match existing. See line items under Section C1 - Description of

Work.

10. Accessories: Fan thermal switch and ventilation-air heat exchanger.

D. Capacities and Characteristics:

1. Fan:

a. Airflow in CFM: Match existing.

b. External Static Pressure: Match existing.

c. Maximum RPM: Match existing.

d. See line items under Section C1 - Description of Work.

2. Fan Motor:

a. HP: Match existing.

b. Number of Speeds: Variable.

c. RPM: Match existing.

3. Furnace:

a. Entering-Air Temperature: Match existing.

b. Gas Input: Match existing.

c. Output: Match existing.

235416-3

2.3 THERMOSTATS

A. Controls shall comply with requirements in ASHRAE/IES 90.1, "Controls."

B. Solid-State Thermostat: Wall-mounted, programmable, Wi-Fi capable, microprocessor-based unit with manual switching from heating to cooling, preferential rate control, seven-day programmability with minimum of four temperature presets per day, vacation mode, battery backup protection against power failure for program settings, and manual override. Voltage rating shall match existing system control voltage.

2.4 AIR FILTERS

A. Disposable Air Filters: Filters shall be supplied with each unit, shall be standard sizes, and not less than 1-inch thick fiberglass media with an ASHRAE 52.2 minimum efficiency reporting value rating of 6 or higher.

PART 3 - EXECUTION

3.1 INSTALLATION

A. Install the furnaces at the locations of the old units being replaced.

B. Install and connect gas-fired furnaces and associated fuel and vent features and systems according to NFPA 54, applicable local codes and regulations, and manufacturer's written installation instructions.

C. Connect condensate drains to indirect waste using PVC drainage piping. Extend to nearest equipment drain or floor drain. Construct vented, deep trap at connection to drain pan, and install cleanouts at changes in direction. Terminate to suit local code requirements.

D. Suspended Units: Suspend from structure using threaded rods, spring hangers, and building attachments. Secure rods to unit hanger attachments. Adjust hangers so unit is level and plumb.

Install seismic restraints to limit movement of furnace by resisting code-required seismic acceleration.

E. Base-Mounted Units: Secure units to substrate. Provide optional bottom closure base if required by installation conditions. Anchor furnace to substrate to resist code-required seismic acceleration.

F. Controls: Install thermostats at a mounting height of 60 inches above floor.

3.2 CONNECTIONS

A. Use existing utility lines and connections as much as possible.

B. Connect gas piping with union or flange and appliance connector valve.

235416-4

C. Install piping adjacent to equipment to allow service and maintenance.

D. Vent and Outside-Air Connection, Condensing, Gas-Fired Furnaces: Connect plastic piping vent material to furnace connections and extend outdoors. Terminate vent outdoors with a cap and in an arrangement that will protect against entry of birds, insects, and dirt.

E. Connect ducts to furnace with flexible connector.

3.3 ADJUSTING

A. Adjust initial-temperature set points.

B. Set controls, burner, and other adjustments for optimum heating performance and efficiency.

Adjust heat-distribution features, including shutters, dampers, and relays, to provide optimum heating performance and system efficiency.

3.4 DEMONSTRATION

A. Upon completion of installation and after circuitry has been energized, the Contractor shall demonstrate capability and compliance of system with requirements. Malfunctioning units shall be corrected and retested by the Contractor to demonstrate compliance with the specifications.

B. Train Owner's maintenance personnel to adjust, operate, and maintain units.

END OF SECTION 235416.13

PACKAGED COMPRESSOR AND CONDENSER UNITS 236200 - 1

SECTION 236200 - PACKAGED COMPRESSOR AND CONDENSER UNITS

PART 1 - GENERAL

1.1 SECTION REQUIREMENTS

A. Submittals:

1. See Section C-4 SUBMITTALS/APPROVALS

2. Product Data: For each type of product indicated.

3. Documentation indicating that units comply with applicable requirements in

ASHRAE/IESNA 90.1.

B. Warranties: Submit a written warranty, signed by manufacturer, agreeing to repair or replace components that fail within five years after Substantial Completion.

PART 2 - PRODUCTS

2.1 PERFORMANCE REQUIREMENTS

A. Verify performance according to ARI 210/240.

B. Electrical Components, Devices, and Accessories: Listed and labeled as defined in NFPA 70, by a qualified testing agency, and marked for intended location and application.

C. Comply with ASHRAE 15.

D. ASHRAE/IESNA 90.1-2004 Compliance: Applicable requirements in ASHRAE/IESNA 90.1, Section 6 - "Heating, Ventilating, and Air-Conditioning."

E. Completion must result in a complete and operable system.

2.2 AIR-COOLED CONDENSING UNITS 1 TO 5 TONS

A. Description: Factory assembled and tested, air cooled; consisting of compressors, condenser coils, fans, motors, refrigerant reservoirs, and operating controls.

1. Units shall be Energy Star qualified with up to a 16 SEER rating, designed for operation on 208/230 Volt, Single Phase, 60 Hz power. The capacity of each unit shall be 48,000 Btuh (nominal) of cooling or greater with air entering the condenser at 95 degrees F, and a saturated suction temperature at compressor of 40 degrees F. Saturated condensing temperature shall not exceed 124 degrees F.

2. The unit shall be designed for operation down to at least 35 degrees F outdoor air temperature entering condenser with standard controls. The unit control system shall provide protection against evaporator freeze up. The unit shall be rated in accordance with ARI Standard 210.

PACKAGED COMPRESSOR AND CONDENSER UNITS 236200 - 2

3. The condensing units shall come with a scroll compressor, timed off control, thermal expansion valve, and liquid line filter dryer and sight glass. Compressor shall operate at 1,750 rpm or lower. The compressor shall have external spring isolators and shall have an automatically reversible oil pump. Maximum input to the compressor shall not be more than 10.2 kW at the conditions specified. The compressor shall unload in response to suction pressure down to at least 33% of full load capacity in at least three steps for partial load operation.

B. Compressor: Hermetically sealed and isolated for vibration. Include thermal-, current-, and temperature-sensitive overload devices, start capacitor, relay, and contactor. The condensing units shall come with a scroll compressor, timed off control, thermal expansion valve, and liquid line filter dryer and sight glass. Compressor shall operate at 1,750 rpm or lower. The compressor shall have external spring isolators and shall have an automatically reversible oil pump. Maximum input to the compressor shall not be more than 10.2 kW at the conditions specified. The compressor shall unload in response to suction pressure down to at least 33% of full load capacity in at least three steps for partial load operation. Compressor shall be located in a section separated from condenser fans and coils. Multiple compressor units shall have step-start fans and coils. Compressor motors shall have part-winding start. Provide oil pressure switch shutdown protection for compressors

C. Refrigerant Charge: R-407C or R-410A. Use manufacturer recommended refrigerant.

D. Condenser Coil: Copper-tube, aluminum-fin coil; with liquid subcooler. Condenser coil shall be of nonferrous construction.

E. Condenser Fan: Direct-drive, aluminum propeller fan; with permanently lubricated motor with thermal-overload protection. Each fan shall have a safety guard. Controls shall be included for cycling fans for intermediate season operation.

F. Accessories: Include the following:

1. Valves for service and charging.

2. High- and low-pressure safety switches.

3. Low-ambient kit to permit operation down to 35 deg F.

4. Crankcase heater.

5. Automatic reset timer to prevent compressor rapid cycle.

2.3 CAPACITIES AND CHARACTERISTICS

A. See Section C-1 (Description of Work) for each project.

B. Cooling:

1. Capacity: Match existing.

2. Ambient-Air Temperature: 95 deg F.

3. Power Input: Varies.

4. Seasonal Energy Efficiency Ratio (SEER): Minimum SEER 16.

C. Single-Point Electrical Connection:

PACKAGED COMPRESSOR AND CONDENSER UNITS 236200 - 3

1. Volts: 208/230.

2. Phase: Single.

3. Hertz: 60.

4. Maximum Overcurrent Protection: 20 Amp.

PART 3 - EXECUTION

3.1 INSTALLATION

A. General: Install new condensing units and new evaporator coils as required by the manufacturer, building codes, and industry best standard; reconnecting the equipment to existing duct system with minor modifications to utility closet space/control panel as required to accommodate the new units.

B. Location: Install equipment as close as possible to the location of the old replaced units.

C. Install units level and plumb. Maintain recommended clearances.

D. Install ground-mounted units on existing 4-inch-thick, reinforced-concrete base. Anchor unit to base using inserts or anchor bolts.

E. Install electrical devices according to NFPA 70.

3.2 CONNECTIONS

A. Connections, flexible duct connections, and duct transitions shall be completed by the Contractor as needed to connect to the existing lines. Flexible conduit and wiring connections shall be used on the AHU if local codes permit. A flexible connection shall be used at the drain connection.

3.3 DEMONSTRATION

A. Requirements: Upon completion of installation and after circuitry has been energized, the Contractor shall demonstrate capability and compliance of system with requirements.

Malfunctioning units shall be corrected and retested by the Contractor to demonstrate compliance with the specifications.

B. Train Owner's maintenance personnel to adjust, operate, and maintain units.

END OF SECTION 236200

B. Warranties: Submit a written warranty executed by manufacturer agreeing to repair or replace furnaces that fail in materials or workmanship within 10 years from date of Substantial Completion.

B. Warranties: Submit a written warranty, signed by manufacturer, agreeing to repair or replace components that fail within five years after Substantial Completion.