Construct the system using acceptable engineering practices for metallic systems designed to contain aqueous fluids. Avoid the use of soft solder, galvanized steel, zinc or dissimilar metal contact in the construction of a system containing CPTherm G. See the Construction Materials section below for more details.
After installing the new cooling system, a thorough cleaning must take place. This can be done with a 1-2 percent solution of trisodium phosphate in water or contact CPI Engineering for additional methods. The trisodium phosphate should circulate for at least 24 hours to ensure a completed and thorough cleaning. This initial cleaning is essential to removing construction debris and also is an effective method of determining the total volume of the system.
Before adding CPTherm G, completely drain the system and check to determine that it is clean. Use fluid in accordance with OEM recommendations. Heat transfer system volume is determined by summing piping component volumes. A volume of deionized water corresponding to the system and component volume is added and adjustments made. Check the system for leaks, then remove a volume of the dilution water equal to the calculated amount of CPTherm G concentrate required and replace with the CPTherm G concentrate.
To ensure the correct dilution was attained, it is recommended to sample and analyze the CPTherm G charge after it has circulated in the system for at least 24 hours. This will help verify that the optimum level of corrosion inhibition and freeze protection were achieved. On site analysis should include measurement of specific gravity and pH. This service is also offered through CPI Fluid Engineering.
Existing Glycol-based Systems
(Consult CPI Fluid Engineering before converting an existing glycol-based system to CPTherm G heat transfer fluid)
Prepare your system as described in the New Systems section, then add CPTherm G concentrate and the calculated amount of water. The use of distilled or deionized water is strongly recommended for any CPTherm G dilutions. Water should be free of contaminants and impurities – the minimum water quality is outlined in Table 2. Potential problems can occur in the system if water impurities are not addressed. For dilution, use distilled or deionized water to prevent increased corrosion, metal pitting and depletion of the corrosion inhibitor package in CPTherm G products. If the recommended water quality cannot be reached, contact CPI Fluid Engineering to obtain a pre-diluted CPTherm F custom blend.
|TABLE 2 / Minimum Water Quality Requirements for Diluting CPTherm™
Materials typically used when constructing heat transfer systems can be used with CPTherm G heat transfer fluids (See Table 3). CPTherm G heat transfer fluids are not recommended for use in systems containing dissimilar metals without proper insulation between metal types because of the potential for galvanic corrosion. Solder, galvanized steel containing systems are not recommended; the later due to its zinc content. In the presence of CPTherm G fluids, zinc can react with the inhibitor package and cause solids formation. This will deplete the inhibitor package and act as a catalyst causing localized corrosion.
Filters are recommended because they remove particles and debris that could react with CPTherm G’s anti-corrosion package. Integration of a 10-micron filter into the system is recommended since this will help protect pumps, piping and heat exchangers.
|TABLE 3 / CPTherm™ Product Application Considerations
Materials of Construction
||Dissimilar metals without proper insulation
||Kalrez seals / elastomers
|EPDM seals / elastomers
|Viton seals / elastomer
To verify the correct CPTherm G dilutions, contact CPI Fluid Engineering.
On-site monitoring should be performed as part of the system’s regular maintenance schedule. These tests include:
Density – A hydrometer is an instrument used to measure a fluid’s density. When purchasing a hydrometer, be sure to order one in the density range with that of the CPTherm G concentration (Figure 5).
|FIGURE 5 / CPTherm™ Density
pH - Use of pH paper with a 9 to 12 range is an easy and acceptable test to check the pH of any system. Another more reliable method is the use of a pH meter (Figure 6).
|FIGURE 6 / CPTherm™ pH
Refractive Index – A refractometer can be used to determine the concentration of the heat transfer fluid. Simply compare the reading from the refractometer with the graph with the graph of Refractive Index vs. Composition (Figure 7).
|FIGURE 7 / CPTherm™ Refractive Index
CPTherm G heat transfer fluids do not pose any special storage problems. Keep container tightly closed. Because of its aqueous nature, the product does not have a flash point. CPTherm G remains a fluid at lower temperatures (-20°F to -30°F). Care must be taken to minimize oxygen intake-ordinary steel tanks may be used. Plastic containers are recommended for storage.
CPTherm G fluids, in its non-contaminated form, are not considered an RCRA hazardous waste per 40 CRF 261. If the material becomes contaminated, a new determination will need to be made. All materials should be disposed of through appropriate licensed, waste handling/disposal companies. Check with these companies and federal, state and local authorities, including your local POTW, for proper disposal methods.