Descaler/cleaner for boiler copper heat exchanger

[pls1]

Got a problem with a Ferroli Tempra 30 boiler (approx 9yrs old) making lots of noise (kettling/vibrating) after running for a few mins & then shutting down. System is an S plan with 12 cast iron rads and a few pressed steel rads.
Both the fan and pump have been replaced but not sorted the problem out so looks like it could be the heat exchanger.
Recently a Magnaclean was fitted and it is collecting plenty of black sludge.
What chemicals are best to try and descale/clean the heat exchanger? bearing in mind its a copper heat exchanger on this type of boiler.

 

[ianmcd]

If it was my own system I would add sentinell X 400 and clean the magna clean every other day but be prepared for the odd radiator to pinhole and need replacing might not happen but be prepared, wont make your Ferroli any better but might last longer sorry but they are absolutely ****

 

[gassafesam]

Buy a new boiler....

 

[muggles]

X900 filter aid is designed to be left in the system and loosen deposits so they get back to your Magnaclean, so I'd use that. Also start saving for a new boiler, this is an old lady by Ferroli standards...

 

[Agile]

To the OP.

Removing the main heat exchanger should only be done by a gas reg engineer.

Black sludge deposits usually need to be dissolved by an acid.

Tony