A 0.2-mm layer of magnetite decreases the power of a heat exchanger by 40% (data from heat exchanger manufacturers).
A 1-mm layer of sediment increases the power consumption of a boiler by up to 9% (test carried out by the University of Illinois and the US Standard Committee).
A well-balanced heating system can save up to 35% on heating costs.
The energy consumption of pumps increases by up to 35% in the first few years due to corrosion and dirt inside the system (published by Rahmeyer, PhD, Utah State University).
A 1°C increase in temperature increases energy consumption by 6-11%.