Alde Heating Boiler corrosion

Alde water heating is a closed loop system for the radiators and therefore requires the water mixture flowing through the system to contain anti freeze / corrosion inhibitor and water in a 50:50 mix.

This water mixture has to be drained and refilled periodically dependant on the previous mixture and type of antifreeze / corrosion inhibitor mix used. Some types last for 2 years and others for 5 (Outdoorbits refills using 5 year mixture saving you time and money)

The below photos show what can happen if the mixture has not been renewed as the corrosion inhibitor deteriorates over time.

Just for comparison, see this picture which shows a nicely maintained alde boiler with no corrosion present.