Subject: Re: automatic radiator slats
Hello Jean-Marie,
I would be very reluctant to disturb this unit if it is working properly. It might break!
For back-flushing we have found Fernox DS3
http://www.fernox.com/?cccpage=ds3 works really well. The biggest worry is that the core may be rotten and once de-scaled might leak, and so need replacing.
I can recommend a very good radiator company who did the core on my 16/80 - Anglian Radiators in Cambridge.
Best Wishes
Colin