Which of the following is NOT tested for in boiler water?

In boiler water testing, various parameters are monitored to ensure safe and efficient operation. Viscosity, which refers to the thickness or resistance to flow of a liquid, is not typically tested for in boiler water. This is because the primary concern in boiler operation relates more to factors that can affect boiling, scaling, and corrosion rather than the flow characteristics of the water itself.

Conductivity is measured to assess the concentration of dissolved ions, which can indicate the overall quality of water and help in controlling scaling and corrosion. Alkalinity is important for maintaining the correct pH level, preventing corrosion and ensuring efficient operation. Sodium sulfite is often monitored because it serves as an oxygen scavenger in boiler systems, preventing corrosion caused by dissolved oxygen.

In summary, the inclusion of viscosity in testing parameters does not provide significant information about the boiler water's performance or condition, which is why it is not a focus in routine boiler water analysis.