Adding fernox concentrated leak sealer to a sealed system

[paul9367]

I am losing pressure and so seem to have a leak. I have seen fernox concentrated leak sealer which I can inject via a rad and says is designed for combi boiler systems. However a plumber acquaintance says I shouldn't use it as it may damage the boiler. Anyone got any advice?
Obviously it would be better to fix the leak but all my floors are concrete!!

 

[hi-spec plumbing heating]

Obviously it would be better to fix the leak but all my floors are concrete!!

thats more likely where the leak is the lime in the concrete has eaten into the copper.
if that is the cause then the whole pipe will need changing or it will happen again

 

[Andy165]

Have used leak sealer on a worcester 24i combi system with seven rads. Expensive laminate flooring down and customer refusing to have it partially uplifted. Customer agreed to the use of leak sealer and it was added via a radiator. 48 hours later boiler required no more topping up and has held its pressure ever since , about 9 months ago and no problems with the boiler or the system reported.

 

[paul9367]

thanks , will give it a go