How to remove sludge from a radiator

After not doing it at the weekend, last night I got a chance to have a look at a couple of the upstairs radiators which needed to be flushed out. Research suggested that they were full of sludge, where the insides of the radiator corrode causing this rust to build up,  and so this needed to be removed. Read about sludge here and also about how it effects your radiator here.

Emptying sludge from a radiator…messy

I turned off the heating, closed the lockshield and thermostat valves, turned off the mains water, and then drained the system. Once this was done I removed the radiators (keeping the valves on both ends), and took them to the bath. It then got very messy.

If these were downstairs (and it wasn’t night time) then I’d be doing this outside and flushing them out with a hose, but needs must and so I used the shower to flush them out as best I could. After putting the valves back on (which I’d removed in order to flush), the rads were put back on, everything else was turned back on and after a nice amount of time I bled the de-sludged radiators (as they were full of air) and they filled with lovely hot water. Job done.

By no means does this mean that I won’t need to get an engineer out at sometime to check over the boiler, but for the moment it delays it and there is now warmth upstairs. Hurrah!

Future plans: There are a couple more radiators which have sludge in so they need to be flushed, and once they are all done I’ll add some central heating cleaning and protection additives.