Section CHEMICAL WATER TREATMENT

Transcription

1 Section CHEMICAL WATER TREATMENT PART 1 GENERAL 1.1 SUMMARY A. Furnish and install all chemical treatment equipment and chemicals and provide necessary service for the indicated HVAC hydronic system(s). A single water treatment company shall be responsible for all products and services. Mechanical Contractor shall be responsible for the installation of water treatment equipment. 1.2 PERFORMANCE REQUIREMENTS A. Water quality for HVAC systems shall minimize corrosion, scale buildup, and biological growth for optimum efficiency of HVAC equipment without creating a hazard to operating personnel or the environment. B. Base HVAC water treatment on quality of water available at Project site, HVAC system equipment material characteristics and functional performance characteristics, operating personnel capabilities, and requirements and guidelines of authorities having jurisdiction. C. Closed hydronic systems shall have the following water qualities: 1. ph: Maintain a value within Conductivity: Maintain a value within µmhos. 3. Sodium Nitrite: Maintain a value within ppm. 4. Tolyltriazole: Maintain a value within 8 20 ppm. 5. Microbiological Limits: a. Total Aerobic Plate Count: Maintain a maximum value of 1000 organisms/ml. b. Total Anaerobic Plate Count: Maintain maximum value of 100 organisms/ml. c. Nitrate Reducers: Maintain a maximum value of 100 organisms/ml. d. Sulfate Reducers: Maintain a maximum value of 0 organisms/ml. e. Iron Bacteria: Maintain a maximum value of 0 organisms/ml. D. Open hydronic systems shall have the following water qualities: 1. ph: Maintain a value within 8.0 to Total Alkalinity: Maintain a value within ppm. 3. Total Hardness: Maintain a value within ppm. 4. Conductivity: Maintain a value within µmhos. 5. Phosphonates: Maintain a value within 4 10 ppm. 6. Polymer: Maintain a value within ppm. 7. Tolyltriazole: Maintain a value within 2 5 ppm. CHEMICAL WATER TREATMENT

2 8. Microbiological Limits: a. Total Aerobic Plate Count: Maintain a maximum value of 10,000 organisms/ml. b. Total Anaerobic Plate Count: Maintain a maximum value of 1000 organisms/ml. c. Nitrate Reducers: Maintain a maximum value of 100 organisms/ml. d. Sulfate Reducers: Maintain a maximum value of 0 organisms/ml. e. Iron Bacteria: Maintain a maximum value of 0 organisms/ml. E. Passivation for Galvanized Steel: For the first 60 days of operation. 1. ph: Maintain a value within Total Hardness: Maintain a value within ppm. 3. Total Alkalinity: Maintain a value within ppm. 4. Passivation Treatment Chemical: Maintain residual as recommended by manufacturer. 1.3 QUALITY ASSURANCE A. HVAC Water Treatment Service Provider Qualifications: A recognized specialist in the field of industrial/commercial water treatment for a minimum of 10 years. The water treatment company shall have regional water analysis laboratories, research and development facilities, and technical service representatives located within the trading area of the job site. B. MANUFACTURERS 1. Bluegrass KESCO, Inc. ( ) 2. Betz 1.4 SUBMITTALS A. Product Data: Provide chemical treatment materials, chemicals, and equipment including electrical characteristics and connection requirements. B. Shop Drawings: Indicate system schematic, equipment locations, piping configurations, and control schematics including electrical characteristics and connection requirements. C. Water Treatment Field Reports: Indicate start-up of treatment systems when completed and operating properly. Indicate analysis of system water after cleaning and after treatment. Verify passivation of galvanized-steel surfaces, and confirm this observation in a letter to Architect. 1.5 MAINTENANCE SERVICE A. Furnish monthly technical service visits and maintenance of treatment systems for two years from Date of Substantial Completion. CHEMICAL WATER TREATMENT

3 B. During technical visits perform field inspections and make water analysis on site. Detail findings in writing on proper practices, chemical treating requirements, and corrective actions needed. Submit copy(ies) of field service report after each visit. C. Provide laboratory and technical assistances services during this maintenance period. D. Provide on site inspections of equipment during scheduled or emergency shutdown to properly evaluate success of water treatment program, and make recommendations in writing based upon these inspections. 1.6 MAINTNENANCE MATERIALS A. Provide sufficient chemicals for treatment and testing during warranty period of two years from Date of Substantial Completion. 1.7 WARRANTY A. This Contractor shall provide an unlimited two year parts and labor warranty beginning at Date of Substantial Completion on equipment provided in this section. 1.8 PIPING SYSTEMS PART 2 - PRODUCTS A. Open cooling tower water. B. Closed loop branch of cooling tower water separated by a heat exchanger. C. Closed loop chilled water. D. Closed loop branch of the chilled water system separated by a heat exchanger. 2.1 EQUIPMENT A. Open Evaporative (Cooling Tower) Hydronic System. Provide the following: 1. One (1) dry contact water meter for makeup meter. Properly size meter for system. 2. One (1), normally closed, 120 VAC solenoid valve for controlled condenser water bleed-off. Properly size valve for system. 3. One (1) microprocessor-based menu driven programmable conductivity/ph controller in NEMA 12X enclosure, with dual 28 day programmable biocide timers, inhibitor timer, conductivity probe, ph probe, flow switch, (4) 120 VAC output power cords for chemical pumps, (1) 120 VAC output power cord for bleed control solenoid, input for contact makeup water meter, and 6 power cord. 4. Four (4) 120 VAC, positive displacement, diaphragm chemical metering pumps with adjustable flow rate, thermoplastic construction, continuous-duty fully enclosed electric motor and drive, and relief valve. 5. Four (4) chemical resistant pump mounting brackets. 6. One (1) corporation stop with quill of insertion length sufficient to discharge sulphuric acid into at least 33 percent of condenser pipe diameter. Corporation stop shall be constructed of brass or other approved material. Quill shall be constructed of CPVC. 7. One (1), ¾, 3-station corrosion coupon rack. CHEMICAL WATER TREATMENT

4 B. Closed Hydronic System. Provide the following: 2.2 CHEMICALS 1. One (1) 5-gallon bypass chemical feeder on each system. Feeder shall be constructed of steel with corrosion-resistant exterior coating, minimum 3 ½ fill opening in the top, NPT ¾ bottom inlet and top side outlet, and minimum 200 psig working pressure. 2. One (1) Harmsco WB-90SC-2 filter housing and two (2) HC/90-20 filter cartridges for the closed chilled loop. A. Open Evaporative (Cooling Tower) Hydronic System 1. Chemicals shall be as recommended by water treatment company that are compatible with the piping system components and connected equipment, and that can attain water quality specified in Part 1 Performance Requirements section. Chemicals shall be premixed, ready to be put online and pumped from their shipping containers. B. Closed Hydronic System (Heat Pump Loop) PART 3 EXECUTION 1. Cleaning chemicals shall be as recommended by water treatment company. The water treatment company shall supervise and document the cleaning process. The water treatment company shall submit written documentation to the Architect that the HVAC hydronic piping systems are clean and prepared for chemical corrosion/scale inhibitor. 2. Scale/corrosion inhibitor shall be as recommended by water treatment company that are compatible with the piping system components and connected equipment, and that can attain water quality specified in Part 1 Performance Requirements section. 3.1 WATER ANALYSIS A. Perform an analysis of supply water to determine quality of water available at Project site. 3.2 INSTALLATION A. Install chemical application equipment on concrete bases, level and plumb. Maintain manufacturer s recommended clearances. Arrange units so controls and device that require servicing are accessible. Anchor floor-mounting accessories to substrate. B. Install interconnecting control wiring for chemical treatment controls and sensors. C. Mount sensors and injectors in piping circuits. CHEMICAL WATER TREATMENT

5 D. Bypass Feeder and Filter: Install in closed chilled hydronic system and equipped with the following: 1. Install bypass feeder and filter in a bypass circuit around circulating pumps, unless otherwise indicated on Drawings. 2. Install gate or full-port ball isolation valves on inlet, outlet, and drain. 3. Install a check valve on inlet after the isolation valve. E. Install automatic chemical-feed equipment for condenser water and include the following: 1. Install dry contact water meter in bypass circuit on makeup water piping. Install water meter cable from conductivity controller to water meter. 2. Install bleed control solenoid valve on condenser water piping. Install power cord from conductivity controller to solenoid valve. 3. Install corporation stop with quill in condenser water piping. Install chemical feed tubing from chemical pumps to injection points. 4. Install conductivity/ph controller with probes and flow switch. Install isolation valves on inlet and outlet of condenser water sampling line. 5. Install chemical metering pumps on chemical resistant brackets. 3.3 FIELD QUALITY CONTROL A. Manufacturer s Field Service: Engage a factory-authorized service representative to inspect, test, and adjust components, assemblies, and equipment installations, including connections. Report results in writing. B. Prior to acceptance by Owner, repair defects or omissions reported by factory-authorized representative. 3.4 DEMONSTRATION A. Engage a factory-authorized representative to train Owner s maintenance personnel to adjust, operate, and maintain HVAC water treatment systems and equipment. END OF SECTION CHEMICAL WATER TREATMENT