In simple terms, corrosion within heating systems is the result of a chemical reaction between elements within the fill water and different metal components within the system. This results in the wearing away of the surfaces of those components, leading eventually to perforation and resultant leaks. An important factor in the likelihood of corrosion occurring is conductivity - a measure of a solution’s ability to conduct electricity. The more dissolved salts present in water, the higher its conductivity.
The likelihood is that you will encounter problems long before the corrosion is advanced enough to cause leaks. The corrosion process generates iron oxide – a black sludge – which will begin to circulate and eventually settle within your system, blocking pipes, radiators, pumps and heat exchangers, damaging seals and having a detrimental effect on its efficiency and operational lifetime.
Large flakes get stuck in heat exchangers
Small bore pipes get blocked
Even magnet filters can have problems
Pipe work virtually blocked
Pumps cannot circulate when the fins are blocked