A04_SOW.pdf

DIVISION 15

MECHANICAL

SECTION 15750

DEHUMIDIFICATION UNIT

TECHNICAL SPECIFICATIONS PAGE 1 OF 6

PART 1 - GENERAL

1.01 DESCRIPTION

A. Furnish and install, as shown in plans and schedule and as specified herein, an indoor heat pump dehumidification system with air-to-water and air-to-air heat recovery. The unit shall be completely factory-assembled, including all internal piping and control wiring. Unit shall be listed by and carry the Label of ETL. The system shall include a compressor , a water condenser, an evaporator coil, an airside condenser coil, a circulating fan, and a microprocessor based control system.

B. Field assembled or modified standard commercial grade equipment is not acceptable. Complete unit shall be weatherproofed for outdoor installation and also suitable for indoor mounting.

C. Unit shall be completely factory assembled, wired, piped and tested with the Test

Report available upon request.

1.02 BASIS OF DESIGN

A. A substitution may be provided in accordance with Specification Section 15010, 1.14.

1.03 OPERATING AND MAINTENANCE DATA

A. Installation and maintenance instructions and an

Owner's Manual shall be supplied with each unit.

PART 2 - PRODUCTS

2.01 CONSTRUCTION

A. The cabinet shall be fabricated out of a minimum of 20-gauge G90 galvanized steel, painted after fabrication. The paint shall be an electrostatically applied polyamide epoxy powder coating, with a thickness of 2-3 mils, baked and bonded at 420°F until it forms a hard, textured surface.

B. Construction shall be modular, consisting of removable panels with permanently affixed fasteners. Base pans shall be formed out of a minimum of 16-gauge G90 galvanized steel with floor mounting support channels. The condensate drain pan under the evaporator shall be formed ABS plastic. The compressor, pool water condenser and controls shall be located in a compartment out of the air stream.

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TECHNICAL SPECIFICATIONS PAGE 2 OF 6

Surfaces adjacent to the coil compartment shall be insulated with fiberglass insulation to prevent condensation. The unit shall be of vertical design, for minimum footprint.

2.02 COMPRESSOR

A. The compressor shall be a heavy-duty, fully hermetic, scroll compressor operating at the scheduled voltage, phase and frequency. The suction gas cooled compressor shall be equipped with thermal overload protection and a crankcase heater to prevent refrigerant migration to the compressor oil during shutdown.

The refrigerant shall be R410-A.

2.03 FILTER RACK AND FILTERS

A. The dehumidification unit shall include a weather tight air filter section with a duct flange and access door for side loading of filters. The filters shall be Class II, one inch, throwaway.

2.04 FAN AND MOTOR

A. The fan shall be a forward-curved, centrifugal blower. The wheel shall be dynamically balanced and installed on a steel shaft. The blower scroll and housing shall be constructed of cold-rolled steel, coated with an electrically applied acrylic enamel paint or G90 galvanized steel.

B. The fan shall operate at the schedule supply air CFM, outside air CFM and external static pressure (ESP), C. The Class B winding fan motor shall be belt drive. The motor shall comply with the efficiency requirements of EPACT-92. The belt drive assembly shall include a single "A" or "B" section belt and an adjustable motor sheave or double "B" section belt and non-adjustable motor sheave depending upon motor horsepower for establishing the specified CFM. The fan motor horsepower, voltage and frequency shall be as scheduled.

2.05 DEHUMIDIFICATION COIL AND AIR REHEAT COIL

A. The coil shall be of adequate face area and rows to remove the specified amount of moisture from the airstream at specified conditions. The reheat condenser coil shall be of sufficient size to reject the required amount of total heat. The evaporator coil shall be constructed of aluminum fins mechanically bonded to copper tubes. The fins shall be polyester-coated for added corrosion protection.

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TECHNICAL SPECIFICATIONS PAGE 3 OF 6

2.06 CONTROL PANEL

A. The control panel shall have a four-line, 20-character LCD display, LED annunciators, and a 15-button key pad. The controller main board shall have all set points and program information stored in non-volatile memory for protection from power failure.

B. The control panel shall be mounted as shown on the plans. All internal circuit boards shall be conformal coated. The control panel shall be connected to the unit by standard six-wire phone cord. The control panel shall be capable of being directly connected to the unit for service convenience.

C. The controller shall be microprocessor based. The following set points shall be programmable at the panel:

Space Air Temperature Space Relative Humidity Pool Water Temperature

D. The following LCD readouts or annunciators shall be provided:

Power On Space Air Temperature Space Relative Humidity Cold Surface Condensation Prevention Temperature Compressor Circuit Fault Unit in Air Heating Mode Unit in Dehumidifying Mode

Unit in Air Conditioning Mode Based on Cold Surface Temperature Auxiliary Air Heating Coil On/Off Service - Diagnostic Codes

E. The unit shall be provided with the following factory mounted and wired control devices:

Space Dry Bulb Temperature Sensor Space Relative Humidity Sensor Water Flow Switch Defrost Controller

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TECHNICAL SPECIFICATIONS PAGE 4 OF 6

F. . The unit shall be delivered with the following factory supplied sensors to be installed in the field:

Cold Surface Condensation Prevention Temperature Sensor

G. An anti-cycle timer shall be provided in the unit control system to prevent short cycling of the compressor. Under normal conditions, the unit fan shall operate continuously, to provide air circulation within the pool enclosure. The compressor shall not operate if the defrost thermostat set point has been reached.

Evaporator coil defrost shall be accomplished by the flow of air drawn across the coil by the unit fan.

2.07 SEQUENCE OF OPERATION

A. All operating and logic controls shall be factory mounted and wired in the unit.

Control sequences shall be designed specifically to control the exhibit environmental conditions. At a minimum, unit shall provide the following functions:

1. Humidity Control:

a. When the humidity is above the set point the controller energizes the compressor and directs hot gas to the air reheat condenser.

2. Space Heating:

a. When the compressor is running in the dehumidification mode the recovered heat is directed to the reheat air condenser. If the space temperature drops more than 2° F below the set point, electric duct heater shall be activated by a dry contact closure from the controller. A further drop in space temperature will activate the second stage of auxiliary heat.

4. Space Humidity Reset Control Based on Cold Surface Temperature:

a. When the temperature of the interior surface at the cold surface sensor drops to within 5°F of the absolute humidity set point (dew point), the absolute humidity set point is offset downward. This condition causes the dehumidifier system to activate humidity control, lowering the space dew point and hindering the formation of condensation on the cold surfaces.

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TECHNICAL SPECIFICATIONS PAGE 5 OF 6

5, Air Conditioning Auxiliary Air Cooled Condenser:

a. In order to achieve space cooling of the exhibit hall by the rejection of reclaimed heat, the dehumidifier shall be equipped with a properly sized remote air cooled condenser and shall automatically change over from heating to air conditioning as a function of dry bulb cooling demand in the exhibit hall.

b. The dehumidification unit shall include external gas and liquid connections to permit piping by the installing contractor to a remote air-cooled condenser provided by the unit manufacturer.

The dehumidification units electrical panel shall have connections for the control of the condenser. The control voltage shall be 24

VAC.

c. The condenser shall have one liquid temperature controlled variable speed 2 horsepower fan motor. The fan motor shall be specifically designed for variable speed operation and have permanently lubricated ball bearings and an internal thermal overload. Fan blades shall be of the aluminum propeller blade type. The fan shall be mounted on a close-mesh steel grill that has been vinyl coated for weather resistance. The condenser shall be of the vertical airflow type. The condenser fan and control wiring shall terminate in an electrical box integral with the cabinet. The condenser cabinet shall be zinc-coated steel covered with a high adhesive, baked on finish. The condenser coil shall be constructed of aluminum fins mechanically bonded to copper tubes. The condenser shall be shipped with a dry nitrogen holding charge.

6. Outside Air:

a. The dehumidification unit casing shall include a manual locking damper with duct collar, to permit the introduction of up to 30% outside air to the inlet of the fan, downstream of the evaporator and reheat coil. Damper assembly shall be of heavy-duty construction, designed for industrial applications. The frame and opposing blades shall be fabricated of formed 16-gauge galvanized steel.

The shaft shall be 1/2" plated steel hex. The opening shall be on the unit's top.

2.08 FIRE TRIP

A. Upon receipt of a contact closure from a fire control system (by others) a fire trip cycle shall be initiated. Compressor and fan motor shall be de-energized.

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TECHNICAL SPECIFICATIONS PAGE 6 OF 6

2.09 FACTORY TEST

A. Refrigeration and electrical systems operation and specifications confonnance shall be verified by factory test prior to shipment.

PART 3 -EXECUTION

3.01 INSTALLATION

A. Comply with manufacturer's printed instructions, except where more stringent requirements are shown or specified, and except where manufacturer's technical representative directs otherwise. Install unit where shown on drawings. Provide three feet clearance around sides and four feet around compressor compartment of unit for airflow and service. Provide and install all water piping, drains and controls for proper operation of unit.

3.02 START-UP, OWNER TRAINING AND WARRANTY

A. All units shall be thoroughly cleaned by the installing contractor in accordance with the manufacturer's instructions prior to being placed into service.

B. Start-up service shall be provided by the equipment manufacturer's authorized representative and shall include complete testing of all controls and unit operation. The agency responsible for start-up shall record the refrigeration pressures and electrical operating data. Copies of this data are to be supplied to the owner.

C. A complete Operating and Maintenance Manual, including wiring diagrams, start-up and operating sequence and material list shall be provided to the owner. The owner shall be provided with complete instruction of operating and maintenance procedures.

D. The unit shall be protected by a one-year limited warranty covering parts and a limited 30-day warranty covering labor. The compressor shall be protected by an additional four-year warranty covering parts only.

END OF SECTION 15750

Base Specifications ADDITIONAL SPECIFICATIONS: In addition to specifications listed in this document, all specifications in the document titled "Dehumidification Unit Specs" must be followed.

REPLACEMENT OF EXISTING UNIT: Furnish and install 1 new R410-A, Split Dehumidification system and accessories. Unit should be a direct replacement for the current Pool Pak Model HCD3500, Serial #PCP0512174. New unit should at a minimum meet the old unit specifications or have higher/better specifications.

RECOVERY & DISPOSAL: Recover refrigerant from old unit and dispose of properly, unhook and remove all necessary materials for removal of existing indoor and outdoor dehumidification equipment.

CONTROLLER: Furnish and install (1) cold surface temperature sensor and Digital Unit Controller

REFRIGERANT LINES: Flush, pressure test and reuse existing refrigeration lines for new equipment.

USING EXISTING SYSTEMS: Hook up new equipment to existing duct system, controls wiring, electrical supply, drains, etc.

DEMO REPAIRS: Replace or (Re}lnstall any piping or any other infrastructure that must be removed to demo, remove existing indoor & outdoor units AND to install new indoor & outdoor units.

LIFTING EQUIPMENT: Provide boom truck, lift or other equipment required to remove old and install new indoor and outdoor units.

DISPOSAL: All old equipment and any construction materials from this job must be disposed of off-site by the contractor, at their expense.

AIR PURIFICATION: Unit should include an ionization air purification system .

WARRANTY: Minimum should be 5 years on compressor, 5 years on dehumidifier coil, 1 year on other parts, 1-year labor.

CONTRACTOR OBLIGATIONS: Contractor is highly encouraged to visit site and view work area before submitting a bid.

SHIPPING: Price to include shipping and delivery to: Wolf Creek National Fish Hatchery, 50 Kendall Rd, Jamestown, KY 42629 270-343-3797