Soft water and combi boilers

[Roger Hersee]

The installer instructions for my new boiler say that you must not fill the (CH) system with water from a softener (although there's nothing about this in the user instructions). Can anyone tell me why (I shouldn't fill with softened water)? I think it may be because the water may be salty if the softener's just recycled and that could attack the heat exchanger. If hat's the reason, I'd assume it's OK to fill with water from the softener well after it has regenerated. Roger

[Andy Hall]

If there is any noticable salt from the softener after regeneration, it has a fault.

[Christian McArdle]

It is fine, provided you have no leaks, you use inhibitor and any plastic pipework is barrier.

The BS that tells you not to use softened water is rumoured to be changing. The original prohibition was around when people didn't habitually use inhibitor and the softened water could cause corrosion.

Christian.