How does a slight drain and desludge work?

[giraffe]

I am going to de-sludge today!

Is right that I should tie up the ball-cock in my F&E tank drain a litre of water from the system and then add X400?

Any help with this gratefully received as I am on the way to B&Q.

 

[oilman]

You need to drain all of the water from the tank, add the Xwhatever add a litre or two of water, then drain the tank again, using a drain point as far away from the tank as possible. (There are other ways as well). then fill the tank up and run it for a couple of weeks before you drain it completely and refill.

Alternatively you could try reading the instructions on the bottle.

 

[giraffe]

Cheers the instructions on these bottles are always a bit vague.

 

[oilman]

I read them. Find them quite handy.

 

[ChrisR]

X400 ones are inadequate, it takes SEVERAL WEEKS to do its stuff.