The presence of water in a heat transfer system is a common occurrence in manufacturing facilities. There are many pathways for water to get into your system. One of the most common avenues is through the improper storage of pails, drums and totes holding heat transfer fluids. Storing these containers outside with exposure to rain and snow and or with improperly closed lids/caps may cause a direct introduction of water into the heat transfer fluid. Operator error has also been known to cause water to get into heat transfer systems. On one occasion, a new hire pumped in water from a tank instead of pumping heat transfer fluid from another tank. This instance sounds ridiculous, but it is a true story indeed.
Moreover, if your manufacturing plant is located in a high humidity area, water vapor can condense into the thermal fluid if the tank operating temperature decreases below the dew point. Using water for hydrotests before the commissioning of piping, vessels, heat exchangers and other process equipment may leave residuals in the equipment. During operation, water leaks from heat exchanger tubes may also be responsible water ingress into the heat transfer fluid. We have also seen operators use the same pump for their heat transfer fluid and an aqueous fluid. This almost always results in water carryover issues eventually.
No matter how water gets into your system, it is one of the most dangerous things that can happen in a heat transfer system. So, you should not overlook it or take it lightly. In the section below, safety implications are discussed.