The approach to the commissioning of a heat-recovery steam generator in the industry has varied from project to project. One school of thought contends that no chemical cleaning (or minimal) is required. The second school of thought contends that a complete chemical cleaning is required. This report discusses these differences, and a properly designed and well executed cleaning with desired results.
If the iron concentration in an alkaline chelant boiler cleaning solution reaches a high value when dissolving magnetite, it sometimes continues to increase rapidly and not level, indicating corrosion of the boiler metal. A laboratory study of “runaway iron increases” investigated the cause and the best mitigation methods.
This technical report applies to water-using cooling and heating systems in buildings. It provides information for minimizing system damage and operational interference because of corrosion, scale, fouling, and microbiological growth in building heating, ventilation, and air conditioning (HVAC) systems. This includes open and closed circulating water systems, low-pressure steam boilers and hot water “boilers.” The document also addresses thermal energy storage systems, but does not address potable water or fire protection systems. It is intended for use by building owners and engineering, maintenance, and operations management personnel. It is also intended for use by those involved in the design and construction of building HVAC systems so that corrosion, scale, fouling, and microbiological growth problems described above can be understood, anticipated, and minimized through appropriate design decisions.