Flushing out central heating system

[jaykart]

Hi all,

I'm just about to switch on my central heating system again after it being off since May.

I've disconnected and re-connected some of the rads during the summer so the system will need to be bled and I was wondering what is the best way to clean out / flush the system before running it up again?

I had some problems last winter with sludge in the pipes so really want to give it a good flush before using.

Thanks in advance.

 

[JohnD]

simple DIY method is to add Sentinel X400 and circulate it round for 4 weeks before draining, rinsing and refilling with an inhibitor such as X100. Each chemical will cost you about £15

There are more aggressive chemicals around that will be quicker, but they are acidic

If you have a Feed & Expansion tank, bale out any mud from the bottom first and sponge it clean. Fit it with a close-fitting lid and an insulating jacket. Verify that the ball valve opens and shuts easily while you are up there.

Verify that all the radiators have filled up with water by bleeding them before you add any chemicals. If you have a blockage it will often reveal itself by radiators failing to fill after decorating. Check that when you bleed the highest rad in the house, water squirts out vigorously and does not die down.

When you add a chemical, tie up the ball valve and drain a bucket or two of water out first so that the chemical is washed down into the system as it refills.

If you have had problerms before with black sludge, and can do simple plumbing, add a Magnaclean to a vertical 22mm return pipe. I guarantee you will be amazed and delighted to see how much black sediment it collects from the circulating water, especially after it has been loosened by X400, and by trapping it, it will also prevent new blockages forming. It continues to work permanently. It costs about £100.

All this will take a couple of half-day DIY jobs to do, but will do a lot of good and may save you the blockages and ineffciencies, as well as the later expense of a powerflush which costs hundreds of pounds.

I am not a pro

 

[jaykart]

Thanks John,

Just the sort of commensense advice I was after.............off to plumb centre for some sentinel X400.

Thanks again.

 

[bengasman]

Look in FAQ for all info on flushing

 

[Agile]

It would be quicker to use X800 as this only takes a few hours!

Its not acidic and like a fast version of the X400.

Tony

 

[David937]

I agree, I used X800 and it took about 6 hours doing each rad individually.