23 25 00 Chemical Treatment of Water for Mechanical Systems.pdf

F-35 SIMULATOR DESIGN

TRUAX ANGB, WI

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SECTION 23 25 00

CHEMICAL TREATMENT OF WATER FOR MECHANICAL SYSTEMS

11/08

PART 1 GENERAL

1.1 REFERENCES

The publications listed below form a part of this specification to the extent referenced. The publications are referred to within the text by the basic designation only.

ASME INTERNATIONAL (ASME)

ASME B40.100 (2013) Pressure Gauges and Gauge Attachments

ASTM INTERNATIONAL (ASTM)

ASTM D596 (2001; R 2018) Standard Guide for Reporting Results of Analysis of Water

ASTM D1384 (2005; R 2012) Corrosion Test for Engine Coolants in Glassware

ASTM D2688 (2015; E 2016) Standard Test Method for Corrosivity of Water in the Absence of Heat Transfer (Weight Loss Methods)

NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION (NEMA)

NEMA MG 1 (2018) Motors and Generators

1.2 SUMMARY

This section covers the provisions and installation procedures necessary for a complete and totally functional water system(s) chemical treatment.

Provide and install the system with all necessary System Components, Accessories, Piping Components, and Supplemental Components/Services.

1.3 SUBMITTALS

Government approval is required for submittals with a "G" designation;

submittals not having a "G" designation are for Contractor Quality Control approval and information. When used, a designation following the "G" designation identifies the office that will review the submittal for the Government. Submit the following in accordance with Section 01 33 00

SUBMITTAL PROCEDURES:

SD-03 Product Data

Water Treatment System; G

Water Analysis; G

Spare Parts

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Field Instructions

Tests; G

Training Course; G

Reverse Osmosis Water Treatment Package; G

Gas Fired Humidifier; G

SD-06 Test Reports

Condenser Water QA Tests

SD-10 Operation and Maintenance Data

Water Treatment System

1.4 QUALITY CONTROL

1.4.1 Safety

Exposed moving parts, parts that produce high operating temperature, parts which may be electrically energized, and parts that may be a hazard to operating personnel shall be insulated, fully enclosed, guarded, or fitted with other types of safety devices. Install safety devices so that proper operation of equipment is not impaired.

1.4.2 Drawings

Because of the small scale of the drawings, it is not possible to indicate all offsets, fittings, and accessories that may be required. Carefully investigate the plumbing, fire protection, electrical, structural and finish conditions that would affect the work to be performed and arrange such work accordingly, furnishing required offsets, fittings, and accessories to meet such conditions.

1.5 DELIVERY, STORAGE, AND HANDLING

Protect all equipment delivered and placed in storage from the weather, humidity and temperature variations, dirt and dust, or other contaminants.

1.6 MAINTENANCE

Submit spare parts data for each different item of material and equipment specified, after approval of the detail drawings, not later than 1 month prior to the date of beneficial occupancy. The data shall include a complete list of parts and supplies, with source of supply

PART 2 PRODUCTS

2.1 STANDARD PRODUCTS

a. Provide materials and equipment which are standard products of a manufacturer regularly engaged in the manufacturing of such products, that are of a similar material, design and workmanship and that have been in satisfactory commercial or industrial use for 2 years prior to

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b. The 2-year use shall include applications of equipment and materials

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SECTION 23 25 00 Page 4 PW\DEN003\708508 April 14, 2020 under similar circumstances and of similar size. The 2 years experience shall have been satisfactorily completed by a product which has been sold or is offered for sale on the commercial market through advertisements, manufacturer's catalogs, or brochures. Products having less than a 2-year field service record will be acceptable if a certified record of satisfactory field operation, for not less than 6000 hours exclusive of the manufacturer's factory tests, can be shown.

c. All products shall be supported by a service organization. Submit a certified list of qualified permanent service organizations for support of the equipment, including their addresses and qualifications. These service organizations shall be reasonably convenient to the equipment installation and shall be able to render satisfactory service to the equipment on a regular and emergency basis during the warranty period of the contract.

d. The selected service organization shall provide the chemicals required, the concentrations required, and the water treatment equipment sizes and flow rates required. The company shall provide all chemicals required for the heating water and chilled water systems and fill the systems with chemicals to the levels specified. The chemical shall meet the requirements of this specification as well as the recommendations from the manufacturers of the chillers and boilers.

2.2 NAMEPLATES

Each major component of equipment shall have the manufacturer's name, address, type or style, and catalog or serial number on a plate securely attached to the item of equipment. Nameplates shall be provided for:

a. Pump(s)

b. Pump Motor(s)

2.3 ELECTRICAL WORK

Electrical equipment, motors, motor efficiencies, and wiring shall be in accordance with Section 26 20 00 INTERIOR DISTRIBUTION SYSTEM. Provide electrical motor driven equipment specified complete with motors, motor starters, and controls. Electrical characteristics and enclosure type shall be as shown, and unless otherwise indicated, all motors of 1 horsepower and above with open, dripproof, or totally enclosed fan cooled enclosures, shall be high efficiency type. Field wiring shall be in accordance with manufacturer's instructions. Each motor shall conform to NEMA MG 1 and be of sufficient size to drive the equipment at the specified capacity without exceeding the nameplate rating of the motor.

All motors shall be continuous duty with the enclosure specified. Provide motor starters complete with thermal overload protection and other appurtenances necessary for the motor control indicated. Furnish motors with a magnetic across-the-line or reduced voltage type starter as required by the manufacturer. Motor starter shall be provided with NEMA 1 enclosures. Manual or automatic control and protective or signal devices required for the operation specified and any control wiring required for controls and devices specified, but not shown, shall be provided.

2.4 GAUGES

Gauges shall conform to ASME B40.100, Class 1, 2, or 3, Style X, Type I or III as required, 4-1/2 inches in diameter with phenolic or metal case.

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2.5 WATER ANALYSIS

Conditions of make-up water to be supplied to the boilers and chilled water systems reported in accordance with ASTM D596 are as follows:

Date of Sample ( )

Temperature ( ) degrees C

Silica (SiO 2) ( ) ppm (mg/L)

Insoluble ( ) ppm (mg/L)

Iron, total (Fe) ( ) ppm (mg/L)

Aluminum (Al) ( ) ppm (mg/L)

Calcium (Ca) ( ) ppm (mg/L)

Magnesium (Mg) ( ) ppm (mg/L)

Carbonate (HCO 3) ( ) ppm (mg/L)

Sulfate (SO 4) ( ) ppm (mg/L)

Chloride (Cl) ( ) ppm (mg/L)

Nitrate (NO 3) ( ) ppm (mg/L)

Turbidity ( ) ntu pH ( )

Residual Chlorine ( ) ppm (mg/L)

Total Alkalinity ( ) ppm (mg/L)

Non-Carbonate Hardness ( ) ppm (mg/L)

Total Hardness ( ) ppm (mg/L)

Dissolved Solids ( ) ppm (mg/L)

Conductivity ( ) micromho/cm

2.6 CONDENSER WATER TREATMENT SYSTEMS

2.6.1 Glycol Solution

Provide for the system a 40 percent concentration by volume of industrial grade propylene glycol, and corrosion inhibitors. Test the glycol in accordance with ASTM D1384 with less than 0.5 mils penetration per year for all system metals. The glycol shall contain corrosion inhibitors.

Silicate based inhibitors are not acceptable. The solution shall be

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2.7 CHILLED WATER SYSTEM

A 5 gallon shot filter feeder shall be provided on the chilled water piping as indicated. The feeder shall be furnished with an air vent, gauge glass, funnel, valves, fittings, and piping. Furnish with one spare bag filter rated at 25 microns and two spare bag filters rated at 10 microns. Install a 25 micron bag filter after the system is flushed and cleaned and ready to be placed into service.

2.7.1 Requirements for Glycol Solution

Provide a 40 percent concentration by volume of industrial grade propylene glycol, and corrosion inhibitors, for the system. Test the glycol in accordance with ASTM D1384 with less than 0.5 mils penetration per year for all system metals. The glycol shall contain corrosion inhibitors.

Silicate based inhibitors shall not be used. The solution shall be compatible with pump seals, other elements of the system, and water treatment chemicals used within the system.

2.7.2 Chilled Water Treatment

Treat chilled water with either a borax/nitrite type treatment or a molybdate type treatment. Both types of treatment can be used with glycol. Borax/nitrite treatment shall be maintained at the limits of 600 to 1000 ppm nitrite, 40 - 50 ppm copper corrosion inhibitor (TT or MBT), and pH of 8.5 to 9.5. Molybdate treatment shall be maintained at the limits of 100 to 125 ppm molybdate, 40 - 50 ppm copper corrosion inhibitor (TT or MBT), and pH of 8.0 to 9.0.

2.7.3 Chilled Water Test Kits

One test kit of each type required to determine the water quality as outlined within the operation and maintenance manuals shall be provided (e.g., pH and nitrite or molybdate).

2.8 LOW AND MEDIUM TEMPERATURE HOT WATER BOILERS AND HEAT EXCHANGERS

Low and medium temperature hot water boilers are defined as those operating below 350 degrees F, (250 degrees F for Low Temperature).

2.8.1 Chemical Feeder

A 5 gallon shot filter feeder shall be provided on the hot water piping as indicated. Size and capacity of feeder shall be based on local requirements and water analysis. The feeder shall be furnished with an air vent, gauge glass, funnel, valves, fittings, and piping. Furnish with one spare bag filter rated at 25 microns and two spare bag filters rated at 10 microns. Install a 25 micron bag filter after the system is flushed and cleaned and ready to be placed into service.

2.8.2 Low and Medium Temperature Hot Water Treatment

Hot water shall be treated with either a borax/nitrite type treatment or a molybdate type treatment. Both types of treatment can be used with glycol. Borax/nitrite treatment shall be maintained at the limits of 600 to 1000 ppm nitrite, 40 - 50 ppm copper corrosion inhibitor (TT or MBT)

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2.8.3 Test Kit Requirements

One test kit of each type required to determine the water quality as outlined within the operation and maintenance manuals shall be provided (e.g., pH and nitrite or molybdate).

2.9 COMMON EQUIPMENT HOT WATER BOILERS AND CHILLERS

2.9.1 Glycol Feeder

Complete packaged duplex system to monitor hydronic system pressure. When hydronic system pressure drops below a set pressure indicating loss of fluid, feed system shall pump glycol solution into hydronic system as required to bring hydronic system pressure back to pressure setpoint.

Provide fully automatic system with one pump for hydronic loop served, controls, glycol tank, stand and all other devices as required for a complete and functional standalone system.

Separate unit to serve the heating water system and the chilled water system.

a. Tank: 50-gallon industrial grade polyethylene storage tank with cover.

c. Drain valve.

d. Inlet strainer and check valve at pump inlet.

e. Pressure gauge for each hydronic system served.

f. Controls:

1. Factory prewired.

2. Adjustable pressure switch for each hydronic system served. Cut in, cut out, and pressure differential as required for system to function effectively at system pressure specified.

g. Main power switch and ON light.

h. Low level cut out float with remote monitoring dry contacts.

i. Include audible alarm.

j. Voltage: 115 volt, 60-Hz.

2.10 Test Kit

One test kit of each type required to determine the water quality as outlined within the operation and maintenance manuals shall be provided (e.g., pH, hardness and sulfite).

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2.11 Reverse Osmosis Water Treatment Package

2.11.1 General: Provide reverse osmosis water treatment

system of size and capacity as indicated on the schedule and delivering this to its holding tank at a pressure of 40+ PSI. The system uses a membrane separation process in which water molecules can pass through the membrane, while the majority of salts and minerals are retained and flushed out the drain. System shall be furnished as a package.

Vendor to include combined distribution skid (RO water treatment system), storage tank, additional system hardware, controls, and all associated devices required for a complete and functioning water treatment system. The RO unit will receive Industrial Soft Water serving other portions of the building that will furnished at typical municipal water temperatures and pressures.

2.11.2 Section Includes skid-mounted package including the

following components:

1. Activated Carbon Filter

2. Five (5) Micron Pre-filter

3. Reverse Osmosis Unit

4. Bladder or Fiberglass Pressure Storage Tank

5. Instrumentation and controls.

6. Single pressure booster pump for pressurizing water to pass thru filters and to maintain a minimum of 45-61 PSI water pressure at the discharge.

2.11.3 Units shall be complete, factory assembled, and tested; and of sizes, arrangements, capacities, and performance as scheduled and as specified. Units shall be capable and designed for year-round, 24-hours-a-day operation; and requiring only connections of piping, utilities, and remote sensors, and controllers. All components exposed to water shall be made of corrosion resistant material

2.11.4 Distribution skid:

Provide reverse osmosis skid assembly, fully factory built and tested. RO skid shall consist of one or more RO membranes, one RO pump that pumps raw water through the RO membrane at a pressure of 116 – 174 psi and into the RO water bladder tank holding a pressure of a minimum of 40 PSI+ for distribution throughout the building.

All components exposed to water are made of corrosion-resistant material. All hoses are steel-reinforced and drinking water-approved.

Low-pressure cut-off switch: A pressure switch just after the inlet filter protects the RO pump from dry running.

The RO pump shall be directly mounted on their electric motors.

Power is supplied to the 3-phase asynchronous motors via a magnet-operated protective motor switch.

The RO water storage tank shall be either a bladder or diaphragm type listed for use with RO water.

2.11.5 Filters

a. Activated Carbon Filter

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Provide a cartridge type carbon filter suitable for removing chlorine, chloramines, tastes, and odors from the water. The media shall be a high capacity black granular carbon with rugged grain structure, high density and large surface area for efficient removal of chlorine/chloramine as well as other taste, odor, and color-causing organics. It shall work effectively over a wide pH range. Filter housing shall be a minimum of 4”x20”

b. Five Micron Filter Provide a cartridge type sediment filter. The filter shall be an absolute filter rated to remove 99.9% of sediment 5 micron or larger in size. The housing shall be a minimum of 4”x20” in size.

2.11.6 The tanks shall be designed for a maximum working pressure of 125 psi (8.6 bar) and hydrostatically tested at 300 psi (20 bar). Tanks shall be made of polyethylene and reinforced with a fiberglass wrapping. Each tank shall include a 2.5 inch (6.35 cm) threaded top opening. Each tank shall be NSF approved.

2.11.7 Control Panel: Mounted on the main pump station frame, includes a manual on/off/auto switch, fault light indicator, service light indicator, and terminal connection for power and control wiring. Display to show required maintenance 48 hours before service is due. Connection glands for power and control wiring.

The control unit which consists of a touch display and a PLC mounted in the IP rated electrical cabinet as well as a power board for the control of the high-pressure pump and connection terminals for power supply. From the touch screen, the operator can view the status of the RO system, water levels in the tank, production, adjust alarm limits, view hour counters, view logged alarms. The pump station is electrically wired at the factory and the control panel must be tested at the factory prior to release.

2.11.8 Controls and Wiring: Factory-installed microprocessor type to control and monitor unit, communicate to central-control processor. The controller shall be connected to the building DDC control system via MODBUS interface.

The unit shall have a factory wired and unit mounted central, electrical control panel with a single power supply connection.

All internal wiring shall be in accordance with the National Electrical Code. Unit shall have a non-fused main power disconnect and control components required for automatic operation based on signals from the humidity controls. Control panel shall have terminals for remote control devices.

Furnish with a pressure switch to start and stop the RO pump as required to maintain pressure setpoint range.

2.11.9 Self-cleaning module/kit of RO Tank (Clean-in-Place):

a. Provide alongside the direct room system and main pump assembly a complete means of disinfection and cleaning in place module that periodically adds or doses the RO tank with a disinfection fluid.

b. The modular self-cleaning add-on box shall comprise a self-priming

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c. The Clean-in-Place add-on panel will be seamlessly connected to the pump skid, via existing embedded software from the main control panel, no additional or external software will be accepted. The add-on self-cleaning module panel shall communicate to the primary control panel on the main pump skid via an Ethernet network cable (RJ45, CAT5 or CAT6), no other means of communication will be accepted.

2.12 Gas Fired Humidifier

2.12.1 General: Packaged unit, floor mounted or wall mounted, gas-fired, steam generating suitable for De-Ionized (DI), Reverse Osmosis (RO) water, without modification required, CSA certified. Coordinate and furnish as required steam distributor(s) suitable for short absorption distance.

Refer to Drawings for performance requirements and coordinate with Air Handling Unit manufactures.

2.12.2 Cabinet and Tank: Shall be fully enclosed powder painted steel construction and air gap between cabinet and insulated humidifier tank.

Evaporation tank and all internal tank components to be constructed of Type 304 stainless steel. Humidifier shall be suitable for zero clearance to combustibles. All tank surfaces shall be insulated with minimum 1 inch (25 mm) thick insulation and enclosed within unit cabinetry to ensure safe surface temperature, high overall efficiency, and fast unit response time. Maintenance shall not require the removal of the steam lines. Internal drain water cooler to ensure drain water tempering to 140 degrees F (60 degrees C).

2.12.3 Electrical: Primary voltage terminal block, internal to cabinet, for single point field connection of electrical supply. Single point natural gas connection with all internal piping from gas inlet to burners must be factory installed and tested.

2.12.4 Combustion System: Gas system with gas valve shall include the following: premix combustion air blower(s), microprocessor-controlled ignition, flame sensing and fault indicator light(s), 100 percent premix infrared burner(s), hot surface igniters(s) and heat transfer efficiency maintained overall operating ranges. Each burner, capable of true modulation will provide steam from full fire to 20 percent of the full firing rate. Time proportioning modulation is not acceptable.

Blower speed rotation must to be monitored to ensure proper control of input modulation. System will lock out gas valve operation if proper blower speed is not detected. A secondary combustion air safety, in addition to blower speed monitoring, utilizing a mechanical pressure differential switch, must be used with each blower to ensure combustion air is entering the premix blower properly.

2.12.5 Water System: Humidifier to prevent “back-siphoning” using an internal air gap for supply water, to meet local plumbing codes. Drain line to include a vacuum breaker to prevent siphon drainage of the tank.

Automatic water level control within a separate float chamber, isolated from the boiling action, to prevent false water level indication. Fill rate must modulate to match capacity demand to ensure consistent

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SECTION 23 25 00 Page 11 PW\DEN003\708508 April 14, 2020 output. Fill cycles based on low water only is not acceptable. Unit water level is to be continuously monitored with a dual magnetic electronic float system, located outside of the boiling water to ensure accurate water level control and reduced maintenance. Tank and float chamber to be separated with a minimum of 1 inch (25 mm) rigid insulation. Humidifier shall have a dual fill valve to feed water to the tank and float chamber, to reduce scaling and mineral build up on the magnetic floats. Float chamber to include LED indication of five possible water level indications. Ongoing self-diagnostics including periodic float operation and fill/drain rate verification. Positive drainage/blow-down using a drain pump, drawing water from the bottom of the tank, maximizing mineral evacuation. Blow down interval shall be based on actual steam production and must be adjustable to compensate for all water conditions.

2.12.6 Controls:

Factory mounted, full size, backlit, Liquid Crystal Display provides full operational status. Display to include a keypad for user interface and adjustment of operational parameters including:

a. Unit output refer to drawings.

b. Water level in the tank.

c. Modulating control demand status.

d. On/off control and safety (High limit, air proving) circuit status.

e. Troubleshooting guide with scroll down menu.

f. Fault indication including date and time history.

g. Maintenance intervals.

h. Fill and drain status.

i. Drain/flush intervals and duration.

j. Date and time.

k. Capacity limitation.

l. 72 hours drain enable/disable.

m. Unit shall be controlled by a Building Management System that will send a calibrated control signal to set the firing rate. BACnet interface for monitoring and control from a Building Management System

(BMS/BAS).

PART 3 EXECUTION

3.1 EXAMINATION

After becoming familiar with all details of the work, verify all dimensions in the field, and advise the Contracting Officer of any discrepancy, before performing any work.

3.2 INSTALLATION

Provide all chemicals, equipment and labor necessary to bring all system waters in conformance with the specified requirements. Perform all work in accordance with the manufacturer's published diagrams, recommendations, and equipment warranty requirements.

Install the Reverse Osmosis Water Treatment Package as required by the written instructions provided by the unit manufacture.

Install the Gas Fired Humidifier as required by the written instructions provided by the unit manufacture.

3.3 PIPING

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Connections between dissimilar metals shall be made with a dielectric union.

3.4 TRAINING COURSE

Submit a schedule, at least 2 weeks prior to the date of the proposed training course, that identifies the date, time, and location for the training. Conduct a training course for the operating staff as designated by the Contracting Officer. The training period shall consist of the following:

a. 4 hours on site training for the chemical feed systems.

b. 4 hours on site training for the both humidification units.

c. 2 hours on site training for the RO unit.

All training hours shall be at normal working time and start after the system is functionally completed but prior to final acceptance tests.

Submit field instructions, at least 2 weeks prior to construction completion, including equipment layout, wiring and control diagrams, piping, valves and control sequences, and typed condensed operation instructions. The condensed operation instructions shall include preventative maintenance procedures, methods of checking the system for normal and safe operation, and procedures for safely starting and stopping the system. The posted instructions shall be framed under glass or laminated plastic and posted where indicated by the Contracting Officer.

The field instructions shall cover all of the items contained in the Operation and Maintenance Manuals as well as demonstrations of routine maintenance operations.

3.5 TESTS

If the waters of the mechanical systems are not in conformance with the specified requirements or in accordance with manufacturer's recommendations, the water treatment company shall take corrective action to enable compliance. Daily operational tests shall be performed in the directed frequencies to maintain required control to prevent corrosion, scaling and damage to equipment during operation Submit test schedules, at least 2 weeks prior to the start of related testing, for the condenser/chilled/boiler/condensate/feedwater water quality tests. The schedules shall identify the date, time, frequency and collection location for each test.

3.5.1 Chilled Water Testing (monthly)

Once a month, the following tests will be performed on chilled water.

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Nitrite or Molybdate ( ) ppm (mg/L)

Conductivity ( ) micromho/cm

3.5.2 Hot Water Boiler Water Quality Testing

3.5.2.1 Low and Medium Temperature Systems (monthly)

Monthly testing shall be completed and recorded for the following parameters.

pH ( )

Nitrite or Molybdate ( ) ppm (mg/L)

3.5.3 Quality Assurance Testing

Conduct QA testing periodically by an independent water treatment lab/consultant to verify to managers that the mechanical and water treatment systems are being maintained properly. Provide the QA evaluation reports to the government COR.

3.5.3.1 Chilled Water Quality Assurance Testing (quarterly)

Quarterly, the following tests shall be performed on chilled water.

pH ( )

Nitrite or Molybdate ( ) ppm (mg/L)

Conductivity ( ) micromho/cm

Iron (total, as Fe(2)O(3)) ( ) ppm (mg/L)

Written evaluation summary

3.5.3.2 Hot Water Boiler Water Quality Assurance Testing

a. Quarterly testing of Low and Medium Temperature Systems shall be completed and recorded for the following parameters.

pH ( )

Nitrite or Molybdate ( ) ppm (mg/L)

Iron (total, as Fe(2)O(3)) ( ) ppm (mg/L)

Written evaluation summary

b. The hot water boiler water shall be analyzed once a month for a period of 1 year by an independent consultant. The analysis shall include the following information recorded in accordance with ASTM D596.

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Sulfite (Na2SO3) ( ) ppm (mg/L)

Hardness(as CaCO3) ( ) ppm (mg/L)

Iron (total, as Fe(2)O(3)) ( ) ppm (mg/L)

Written evaluation summary

3.5.4 Corrosion Testers

Install corrosion coupon and rack systems to verify corrosion control in the systems. Testers or coupons are installed in flowing system water through a sidestream or rack system. Both mild steel and copper metal samples are to be tested in the corrosion testers in accordance with ASTM D2688. Samples are to be replaced and analyzed every 3 months.

Rates of corrosion less than 3 mpy for steel and 0.2 mpy for copper are acceptable. Corrosion testers shall be installed on the piping systems of the following systems.

Chilled water system Hot water loop

3.6 INSPECTIONS

3.6.1 Boiler/Piping Test

Thirty day after project completion, inspect the boiler piping and chilled water piping for problems due to corrosion and scale. If the boiler or chiller is found not to conform to the manufacturer's recommendations, and the water treatment company recommendations have been followed, the water treatment company shall provide all chemicals and labor for cleaning or repairing the equipment as required by the manufacturer's recommendations. If corrosion is found within the condensate piping, proper repairs shall be made by the water treatment company.

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