Kitchen mixer with pull-out spray - compliance with Water Regs?

A friend of mine has bought one of those kitchen mixers with a pull-out spray and has asked if I can install it. I took a cursory look at the instructions and have read the following.


It could be a criminal offence to use this tap with water supplied by a Water Company. (The supply pipe is the one which brings the waters supply into your home and is directly connected to the public water main).


This tap has an outlet on a flexible hose which, if left immersed in water could result in contaminated water being drawn back into the pipework if the supply pressure dropped. To prevent contamination of drinking water in the premises and in the water main, and to comply with the legal requirements of the UK plumbing regulations and byelaws (Water Regs 1999), both hot and cold water supplied to this tap must come from a storage cistern.


Has anyone fitted this sort of item before and if so did both the hot and cold supplies really have their own storage cisterns? I cannot envisage having seen any sort of setup like that previously. Would appreciate any comments.

 

Thought they retracted when you stopped using them, have to admit I`ve never fitted one myself.

 

I would have thought you can fit it if you use something like this https://www.bes.co.uk/double-check-...08XF77SXcMc4aAlPMEALw_wcB#product-details-tab in the supply pipes as you would with an outside tap.

 

It might just be bum covering, classing it as a higher risk fluid category, as they don’t where the tap is going to be installed, eg a butchers shop. I personally wouldn’t recommend it as you’re supposed to have access to potable (fit for human consumption) water available, and a tank fed would not meet this requirement.

A worthy read?
https://www.wras.co.uk/consumers/resources/glossary/type_auk3/

 

Would need to check the regs again but I think dirty/soapy dish washer might be classed above CAT3 water therefore an air break would be needed for the cold water at least, if not the hot, if they are both mains fed.
Strictly speaking running it from the mains wouldn't be allowed if it classed above CAT3 but a verifiable double check valve on mains fed, would certainly go some way .

Usually these taps have a flexi pipe that has a weight attached to the pipe under the sink, that then pulls the tap head back into the tap when let go but I guess it could still sit in the dirty water and therefore a potential backflow contamination risk.

 

If you set the counterweight on the flexible hose so that the head on the end of the flexible hose is 20 mm above the spillover level of the sink you should be OK (AUK3 air gap). I'm fairly certain a double check valve is not considered a sufficient guard against contamination. A kitchen sink is likely to have fluid category 5 as they are often used for washing meat and poultry.

As for using them with stored water, most houses in the UK wouldn't have sufficient head to allow many of these taps to work.

 

Guys, just to convey my thanks for some very interesting comments. Suffice to say I persuaded matey to return the said mixer and obtain a straight forward, no messin' Franke job, sans extendable hose. I remain amazed that they can get away with selling this sort of thing.

Thanks, again.

 

The water regs (vital for our health) are constantly being eroded by illegal imported fixtures/fittings.
Take a look at Islamic douches, they used to be confined to Mosques but are now commonplace in homes....they are non compliant and there is no simple way to install them legally.
Nothing is being done to prevent the sale or installation....

 

I am directly employed by LL and if I see one I always try to disconnect it telling them it’s an illegal installation, and if they don’t let me, then I would report them to my local water undertaker for them to deal with also if it’s part of pipework I’m changing then I legally have to remove it, can’t reconnect it as I’m then in breach of regs. There’s too many people (including some colleagues) who don’t care about the water regs, I always tell them that the could be drinking foul waste, usually persuades them we have some customers who “need” them as part of their religion, I have told managers not to ask me to install them unless they want the job spread out and costly

We also have other trades undertaking plumbing bathroom suites and kitchens, all in Hep2o, not bothered about undue warming (hot pipe under cold), backflow prevention on shower heads etc

 

"could result in contaminated water being drawn back into the pipework if the supply pressure dropped. "
I can understand water pressure reducing, but how could mains water pressure actually become negative, sucking water (or air) back up the public pipework? I live in an area where the mains pressure is very good.
I intend to fit one of these taps but with regard to the warnings, I will ensure that it does not reach out more than a few inches, just enough to allow the spray to be directed around the sink

 

I have heard stories of Water Inspectors being threatened when they've visited premises with these things illegally installed and ordered they must be disconnected and/or removed until they can be made to comply with UK Water regs.

 

The same way as a hose used to syphon liquid will suck liquid up and over the top of the hose.

 

But how? I have some understanding of siphoning, but you need suction to get that process going too. How can you have negative pressure in a mains water pipe? A link to a diagram might help me.

 

One notable cause could be a burst water main. At some point the supply will have to be turned off to fix the burst, and any low lying pipework could theoretically drain back, causing a suction effect behind it. Therefore any outlet that is open and immersed below water that is higher than the burst point could draw that water back into the supply, e.g. a Garden hose filling a pond or paddling pool.