build up of scale in ferroli 901 combi boiler

[nobby6]

Boiler is 4 years old and over the last few months domestic hot water flow has become appalling. Ferroli tell me that there is nothing in the boiler that can be adjusted and that it must be a blockage or the boiler has become furred up inside. (we do live in a hard water area)

Took boiler apart to have a look and all seems OK (ie gauze filter is clean, all taps etc are fully open) Water flow into boiler I have measured at 8 litres per minute, but water flow directly out of heat exchanger is only 4 litres per minute so it must be furred up !!!

Question is:- Do I need a new heat exchanger and associated engineers costs, or is it possible to use any sort of descaler ? I know this would be a bit if a "faff" to do, but it could be a lot cheaper surely?

Thanks for any advice

Rob James

 

[breezer]

if it is of any use we had to have our heat exchanger changed (it was furred up) after about 5 years

 

[ollski]

yes you can put a descaler into your heating system which may clean up your heat exchanger, but if it works fit a magnetic descaler on to your incoming mains. BG for example insist on this in a hard water area in order to be taken on contract. Or of course you could replace the heat exchanger.

 

[DP]

Smallest combi will deliver 9.5 liters of water a minute. At 8 you do not have sufficient water flowing through the boiler. Scaling will make things worst.