To prolong the life of the central heating system, the most effective maintenance you can carry out yourself is to make sure that the system is properly filled with corrosion inhibitor. This is important, and the components of the system (boiler, pipes and radiators) will not last long without protection. To find out whether or not your system has protection, do the following test. East London Plumbers can sort this.Draw off a water sample from one of the bleed taps at the top of the radiator when the system is on and the water is hot (take care not to burn yourself). Put the water in a jam jar and drop in a shiny new steel nail. Fill in this another jar with ordinary tap water and place a similar nail in it. After a couple of days, the nail in the tap water will go rusty as corrosion begins. On the other hand the nail in the radiator water should remain bright. If it does, your system doesn’t need to have corrosion inhibitor added, but if it starts to go rusty, you need to add the inhibitor. If the water bled from a radiator is black and murky, this is called sludge. The system needs to be flushed out with a proprietary chemical. To do this, tie the ballcock in the feed and expansion tank to a stick set across the top of the tank so that the water can flow into the tank. Drain the system by opening the drain cock at the lowest point in the radiator pipe work. Pour the flushing chemical into the feed and expansion tank and then allow the ballcock to partially fill the tank, at which point the flushing chemical will be drawn into the system. While some products require slightly different procedures, the next step usually involves draining the system and washing out all the flushing chemicals and sludge. Finally, refill the system with water and corrosion inhibitor to protect everything from rusting, and the job is done it sounds a bit complicated, but in fact it’s quite easy to do. An East London Plumber is qualified to do this. You won’t go far wrong if you follow the instructions supplied by the manufacturer of the flushing chemical.