To protect the pump whilst the cleaning routine is carried out, a good idea is to remove it, the integrity of the system can be maintained using a length of pipe. When complete, with pump back in place, it is much easier to turn the pump impeller with a screwdriver before the system is run, this is done in order to make sure it’s clear and free to spin. If you can feel resistance, drain the system and remove the pump again, and clean and refit the impeller if required. Of course at any point if you are not confident, call a professional plumbing company like South Kensington Plumbers for a reliable service.


NOTE:
After an installation or modification of a central-heating system, the system and associated pipework should always be flushed through with water to get rid of any foreign objects and flux that can be left behind during the process. This debris if left in the system can cause corrosion or damage to the valves and more importantly the pump. Professional tradesmen like a South Kensington Plumber will carry out this work as standard.


Using a strong cleaner may show up minor leaks sealed by corrosion so a mild cleanser is the best option which should be fed into the system through the feed-and expansion tank or a radiator through its bleed valve.

A good regime is to run the cleanser through the system for a week, with the boiler set to a fairly high temperature.

When complete, turn off and drain the system. Refill and drain it several times, using a hose to run mains-pressure water through the system while draining it. Should the boiler be making loud banging noises, treat it and its immediate pipe work with quite a powerful descaler. Run this on the hot water program only. There are some agents that must be neutralised before you can add a corrosion inhibitor.