Noisy Bolier

[chairman]

Please help!!
I inherited a Baxi burmuda back boiler which was new at the time 5 years ago when i moved house. the system is a fully pumped open vent system.
This boiler when installed was fitted to a one pipe system which i had updated to flow and return with new rads. Part of the pipe work is old steele threaded pipes leading from the boiler to the cylinder.
My problem is noise like kettling/banging and whistling.
An engineer comes every now and again and adds a pink liquid which he states is a desludger and limescale remover which seems to do the trick but for a limited time.
He has diagnosed the problem as limescale in the boiler with sludge which is treatable but will take time. I don't want to bother him every five mins and am capable of adding stuff to the system, but what? It has to be non acid based because of the old pipes.
Any ideas gratefully received

 

[COG]

Sentinel x400 is an alkaline based sludge remover , very easy to use about £10 to £15 per ltr ,ideal for older systems .make sure your drain points are at the lowest parts of the system ,if not fit some.x200 is a descaler also good you should find both in your local plumb center

 

[oilman]

Some branches of Homebase and B&Q also have a suitable selection of chemicals, May be Sentinel, Fernox, or other. Try looking some up on the net and then browse the shelves. There's nothing critical except if you have aluminium in the system.

 

[ollski]

generally points to the fact the boiler is on its last legs....take it the burner pressure is reduced to the lowest you can get away with?. Will the system not stand up to a powerflush?

 

[oilman]

If the boiler's on its last legs after 5 years, I'd change to oil . I regularly see 20 to 30 year old boilers with no problems except if you need spares they might be difficult to get.
Next summer it might be worth disconnecting the boiler and descaling it as a seperate unit.

 

[ollski]

didn't notice the 5 year bit....but if the heat exchanger is scaled up and only gets a temporary reprieve from a clean out things can only go downhill

 

[chairman]

thanks for the advice.....don't want to put anything into the system which will render it u/s during the winter.....will probably replace next summer.