Combi boiler: Water Softener a good idea?

[Mr Fizzion]

To quote the installation manual for the Greenstar 40 HE plus:

-------------------------------------------------------- "In exceptionally hard water areas a device to prevent scale formation may be fitted or, alternatively, the maxi- mum temperature reset to about 45°C which may reduce the risk of scale formation. The installation of a scale inhibitor assembly should be in accordance with the requirements of the local water company. Artificially softened water must not be used to fill the central heat- ing system. An isolating valve should be fitted to allow for servicing. "

-------------------------------------------------------

According to Wessex Water, my water hardness is 280 ppm, which is classified as hard.

Should I install a softener?

Is it a good idea to set the maximum temperature to 45C? (Presumably this is the DHW temperature?) Would this result in any loss of efficiency?

Thanks

Mr F

[Christian McArdle]

Your choice is:

1. Ion-exchange softener, which will have additional benefits, such as preventing horrible stains on the sink/bath/toilet, feeling nicer on the skin and using much less detergent. They cost a lot.

1. Phosphate dosing capsule, which will reduce scaling on heating appliances, but have few additional benefits. They have moderate cost.

2. Electronic/magnetic conditioner, which help boost the bank accounts of the charlatans that sell them.

It would increase both safety and efficiency, as it help reduce the boiler return water temperature. It would help a shower mixer remain at a stable temperature and flow. The main disadvantage is that it isn't so good for washing dishes.

Christian.

[Andy Hall]

Can be as little as £300, which vs. £100 or so for phosphate doser is not a huge jump.

The consumable (salt grains or tablets) for a softener are offset by savings in detergents and shampoos.

[Doctor Drivel]

Strange that the many major cylinder and boiler manufacturers recommend them. I think W-B recommend them too. Gledhill, a quality company, do.

If you have a dish washer that is really not an issue.

[Doctor Drivel]

£100? They around £45 in the sheds inc' canister.

Not much.

[Mr Fizzion]

Must a water softener go in the kitchen? I don't have a utility room, and intend to put the new boiler in the loft.

I guess it wouldn't be practical to put the water softener in the loft due to the frequent need to refill with salt?

Mr F.

[Christian McArdle]

The problem is putting it near the water path to the outlets that you require to be softened. In most houses, the incoming water main passes through the kitchen and outlets are taken off either directly or via a tank in the loft.

If you have a loft tank, the water softener can be anywhere on this line, including the loft. If the cold water outlets are taken off at mains pressure before the loft, the softener must be installed before those take offs (but after the kitchen drinking tap and the outside tap).

A modern metered softener doesn't actually use much salt. I wouldn't hesitate to put one in an easily accessible loft, except that my house is entirely mains pressure, so the softener must be placed in the kitchen. When repiping the kitchen, I used a three pipe solution, with hard cold, soft cold and soft hot pipework. Unfortunately, I can't actually afford a suitable high flow softener ATM, so the soft pipework is hard.

Christian.

[Christian McArdle]

No doubt they do, for commercial reasons. I have no trouble with the charlatans selling snake oil. Good luck to them.

Indeed, if you don't mind boiling an occasional kettle when handwashing pans.

Christian.

[Doctor Drivel]

It seems they think different to you. Companies with reputations to protect do not recommend crap.

45-50C is enough to handwash a pan.

[<me9]

I currently use condensate from my dehumidifier to top up my CH (sealed system). It was originally filled with tap water and fernox inhibitor.

Is this a good thing or bad?

[Mr Fizzion]

I always thought water became too hot for hands at around 40 degrees. This site

seems to confirm that.

"Even though this is a 'relatively-safe' temperature, exposure to water set at 110° F is painful; the human pain threshold is around

106-108° F"

110 = 43.3 C

108 = 42.2 C 106 = 41.1 C

Mr F.

[Doctor Drivel]

True. Most people have 55-60C from the kitcehn tap and mix it down with cold in the bowl or sink.

What keeps temps high is the Legioneella bacteria scare.

[Christian McArdle]

Just use tap water. A lot simpler than pressurising the condensate. The condensate may have all sorts of cr*p in it, too. Even hard water doesn't matter, as you shouldn't be topping up frequently.

Christian.

[Andy Hall]

OK, so it's £250 instead of £200 difference. Big deal.

Entirely.

[Andy Hall]

You could put the softener there as well, but again it needs to be kept from freezing. It also requires a drain, although that could go via a trap into the soil stack or something like that.

You could. Mine gets through a 25kg bag about every month, so one could carry 5kg a week up and add to it.

[OldBill]

In a hard water area the cold inlet to the boiler's hot water heating circuit should be softened, with an ion-exchange softener, as it will scale up in no time if not.

I don't believe actually filling the sealed side of the boiler with soft water makes any difference, I do. To have a separate un-softened feed to top up the boiler with would be an extra pain to provide and would be nigh on impossible on those boilers that have a built in filling loop.

[The Natural Philosopher]

No. 50C is getting hot and 60C is very painful.

40C is barely above blood heat.