Flushing/Cleaning central heating system?

[mattgriff88]

Hi

I have recently bought a house which is 17 years old.
There was a small leak from one of the radiators So I took the pipe off and drained the radiator and the water was black/brown.

I took the radiator off and flushed it out with a hose pipe out the garden but it's got me thinking and I now want to clean the whole system the best I can.

Just looking for some advice really on what the best way to do this is as I have never done it before.

Shall I take each radiator off one by one and flush them out with the hose pipe and then run something like sentinel 400 for a few weeks and then flush the whole system out again?

Hoping to replace the radiators completely in a year or 2 once I have saved up enough cash but looking to clean everything out to get me by until I do.

I have a unvented system boiler if that makes any difference.

 

[Walkleyboy]

From recent experience I can say that X400 is good at cleaning the gunk from a CH system. In my case, I ran the system with X400 for three weeks then drained down. Probably worth refilling with plain water, running for a short while, then draining again to see if there's any residual gunk still lurking.

 

[H Tomm]

Hi

I have recently bought a house which is 17 years old.
There was a small leak from one of the radiators So I took the pipe off and drained the radiator and the water was black/brown.

I took the radiator off and flushed it out with a hose pipe out the garden but it's got me thinking and I now want to clean the whole system the best I can.

Just looking for some advice really on what the best way to do this is as I have never done it before.

Shall I take each radiator off one by one and flush them out with the hose pipe and then run something like sentinel 400 for a few weeks and then flush the whole system out again?

Hoping to replace the radiators completely in a year or 2 once I have saved up enough cash but looking to clean everything out to get me by until I do.

I have a unvented system boiler if that makes any difference.

Fernox F3 is one of the most often recommended cleaners. Their instructions say to first drain and refill the entire system with plain water. Makes sense - you wouldn't wash anything in dirty water.

To remove hardened iron oxides and limescale, the cleaning time can be up to one week.

I would flush again afterwards then refill, not forgetting to add fresh inhibitor.