how do i use ch cleanser?

[johnnyG]

hi all,
just done some work on ch system and noticed slight black sludge in pipes etc.The system is a 6 year old combi with 7 rads. I realise i should put some cleanser through but how is this done? Do i need the concentrate which comes in a tube, or do i use the 1lt can options? Do i need special funnels etc to feed through the rad? Am sure when the system was first installed the engineer pumped it through the bleed valve via a spider gun. also, how long is the norm to leave it in , and do you have to flush through with clean water after.
Idiot proof instructions on this would be great,
thanks, john

 

[Deleted member 261]

hi
dont think its a diy job for the first time as you have an old combi it will brobably perforate your diaphragm on you diverter valve you are probably beter of geting someone in to do it and proper service the boiler at the same time. Its a simple thing until it goes wrong

 

[johnnyG]

Thanks for the replies guys, will have a think about my best options with it.
Cheers, john