Water reviews, policies and action plans

Reduce water use from heating and hot water systems


You can face significant costs and potential water losses from boilerhouses and other heating systems. The value of water used is often underestimated, despite hot water representing a major cost to your business.

It is important to understand how your hot water systems and boiler use water. Often not all water and steam is returned to the boiler for reuse. Evaporation and blowdown can occur, which means that new 'make-up water' has to be added. Improving the reuse of lost water in your hot water systems can bring significant cost savings.

Pre-treatment of water

Demineralisation or softening often occurs when water is pre-treated before entering a boiler using ion exchange columns. These columns require regeneration typically using hydrochloric acid/caustic soda for demineralisation plants and salt solution for softening plants. These processes use more water and chemicals, and also generate effluent. Optimising how often ion exchange columns are regenerated will minimise costs and environmental impact.

Boiler blowdown

Blowdown removes impurities from your boiler preventing the build-up of total dissolved solids. Blowdown can be controlled manually or via timers and conductivity measurements. Boiler blowdown should be discharged to sewers and not your surface water drain.

Steam recovery

The water that is turned to steam (condensate) is very valuable to businesses. Where possible, steam should be collected and returned to the boiler hotwell as this reduces the energy required to heat new water. Because steam is usually low in total dissolved solids, your ion exchange costs are also reduced.

Steam losses and leaks

The cost of generating and distributing steam is often underestimated - to produce steam at 100 degrees Celsius requires the energy equivalent of heating water to around 650 degrees Celsius. You should keep losses from leaks and poorly maintained steam vents to a minimum with regular maintenance checks and repairs.

For information about reducing the energy used by heating and hot water systems, see how to use heating and hot water systems efficiently.