Water softeners and combi boiler heat exchangers

[Glebester11]

Just had new Grant 26e combi installed (by same plumber who installed Aquadial water softener). Central heating system filled by unsoftened water as normal but all other water, including water going into boiler for hot water goes through the softener - I thought nothing of it as trusted plumber but am not told (by different plumber) that I can't have softened water going into boiler at all. Read up and it looks like this is only true for boilers with aluminum heat exchanger, but Grant web literature indicates 26e heat exchanger is steel. Anyone have any info on whether I can or cannot run softened water through a combi boiler - and if not why not. Thanks

 

[dreadnoughtheating]

Certainly your installer is correct to use untreated water for the system, I would suggest you contact Grant techie guys to get confirmation (in writing/eMail preferably) as to their views on this.

In the Gas World, Alpha have no such qualms. (I do not fit Aphas BTW...)

DH

 

[Dan Robinson]

If you don't have ali rads or HEX then there isn't a problem AFAIK.

using hard water in a CH system isn't the end of the world either.

 

[Onetap]

Just had new Grant 26e combi installed (by same plumber who installed Aquadial water softener). Central heating system filled by unsoftened water as normal but all other water, including water going into boiler for hot water goes through the softener - I thought nothing of it as trusted plumber but am not told (by different plumber) that I can't have softened water going into boiler at all. Read up and it looks like this is only true for boilers with aluminum heat exchanger, but Grant web literature indicates 26e heat exchanger is steel. Anyone have any info on whether I can or cannot run softened water through a combi boiler - and if not why not. Thanks

The water in the CH system shouldn't be softened. The amount of scale introduced is minimal since the water should stay in there until drained.

The water going through a combi DHW heat exchanger should be soft, softened (not the same) or otherwise treated to prevent the formation of limescale on the heat exchanger. I think the manufacturer's installation instructions will have some requirements about this.

The waterways are narrow and are soon blocked by scale deposits from hard water

 

[Glebester11]

Thanks guys for the useful replies. Just want to confirm - CH system is on hard unsoftened water - softener was bypassed to fill it - and bypassed if ever I need to top up. It is the hot water supply that is in question - the softener is on the mains side of the water supply so hot water supply goes mains - softener (currently turned off) - boiler and out of the tap - it is this bit of the process that is up for discussion and which I'm now being told I cant do. Any thoughts?
Regards

 

[Agile]

I am not aware of any manufacturer who will not let you do that!

Tony

 

[mickyg]

its fine, actually the best scenario possible.

 

[Glebester11]

Brilliant, thanks for the really speedy reply - I'll go back and try and get something confirmed in writing and take it from there.

thanks