Need help with water softener installation questions!

9 Feb 2008
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United Kingdom
Hi guys

I'm getting a water softener installed which is to supply the whole house, and I need some help with some questions I have. It's the Wickes E10T softener which seems cheap and cheerful but has good feedback.

We have a small 2 bedroom house which is heated by a Worcester 28i rsf combi boiler. The manual for the E10T softener specifically says when using a softener with a combi boiler...
For households with combination boilers i.e. connected directly to the mains water supply without a cold water storage tank, it would be advisable to disregard the hoses and plumb the softener directly using all 22mm pipe work valves and fittings etc, especially the non-return valve. This would give significantly greater flow and less pressure drop across the system therefore minimizing any low pressure effect on the combination boiler and all the mains water system through out the house.

Now my water pipe from the street seems to be around 22-25mm in size. However that immediately narrows to a 15mm stockcock and then expands back out into a 22mm pipe. From here this travels a few meteres to the kitchen area and which point it narrows again back to 15mm and this is the size is remains from here on in all around the house.

Now this is concerning me considering the quote from the manual above. I could ask my plumber to increase it to 22mm at the softener install area on the pipes, but would I actually benefit at all considering the pipe has already narrowed to 15mm at the stopcock and then again earlier in the pipe run.

Does it make any difference at all returning back to 22m pipe at the sink area purely for the softener? Obviously it's going to narrow back to 15mm again afterwards which is why I doubt it.

Any clues guys? I'm in a quandry here. I also notice I can buy 15mm or 22mm installation kits, the 15mm kits come as a 'full bore' option with larger 19mm flexi hoses to the softener, would this be enough?
The reason I'm keen to see I don't lose too much pressure is we have a brilliant mixer shower that simply runs off mains pressure, and I understand the softener is likely to reduce the flow, I'd prefer it didn't drop more than is required.

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The only advice I can give is that you shouldn't really be using softened water in your heating system
the filling loop should be upstream of the softener

Hi Matt

Unfortunately that's not really possible without almost a complete replumb of the entire house. The water softener is at the start of the pipework, and the combi boiler is right at the end in an upstairs bedroom!
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Actually Matt, I just thought about it properly and realised using softened water to fill the CH system won't be an issue as I can bypass the softener if needed with the bypass valve and therefore use hard water in the system.

Would it be logical to assume a 50/50 split of soft and hard water in the CH loop would be a good mix?

Instinct would be no...... but far better 50/50 than 100%
I don't know enough about using softened water in heating system to advise
only that a lot of manufacturers advise against it
others on here may have had experience with such systems though


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