Refilling central heating system

[edwardings]

I've had a problem with my boiler kettling, so its been switched off and i'm using the immersion. Had some pipes altered and the plumber back filled the system as the cold feed was blocked. I'm guessing then not much inhibitor got in the sytem causing scale to build up? Anyway I have cleaned out the tank, so its free of sludge and flushed the cold feed with a hose pipe. Seems to be ok now.

My question is do I add X100 + X200 togther in the tank? as I need to clear the scale. Or is it best to clear the sludge/scale, drain the system and refill with X100?

 

[D_Hailsham]

Had some pipes altered and the plumber back filled the system as the cold feed was blocked. I'm guessing then not much inhibitor got in the system causing scale to build up? Anyway I have cleaned out the tank, so its free of sludge and flushed the cold feed with a hose pipe. Seems to be ok now.

If the cold feed is blocked, flushing doesn't usually clear it. Did the plumber cut out and replace the cold feed?

My question is do I add X100 + X200 together in the tank? as I need to clear the scale. Or is it best to clear the sludge/scale, drain the system and refill with X100?

If you just add it to the tank, it will stay in the tank.

Tie up the ball valve
Drain the system until water level is just above the lower outlet. (If the level does not go down, the cold feed is still blocked.)
Add the X100 and X200 to tank.
Untie the ball valve and let tank fill.
Tie up valve again
Drain until level is just above outlet. (this gets X100 and X200 into the system)
Untie ball valve.

Job done.

 

[edwardings]

If the cold feed is blocked, flushing doesn't usually clear it. Did the plumber cut out and replace the cold feed?

No, he left it blocked. Well it worked abit, but was very slow at refilling. The tank is completely empty atm, as I had to remove all the thick black sludge. I'm quite sure the cold feed is fixed, as I had the hose stuck in the tank outlet running at full pressure to clear it. It didn't back up the pipe, so must be ok.

Tie up the ball valve
Drain the system until water level is just above the lower outlet. (If the level does not go down, the cold feed is still blocked.)
Add the X100 and X200 to tank.
Untie the ball valve and let tank fill.
Tie up valve again
Drain until level is just above outlet. (this gets X100 and X200 into the system)
Untie ball valve.

Job done.

Excellent, thanks. How long should I run the heating for to circulate the X100+X200?
My system is pumped CH, Gravity DHW if this makes any difference.

 

[powell30]

My guess is you would be better off getting the system power flushed. Sounds as if it's sludged up badly

 

[bengasman]

Defo need cleaning