Any electricians? looking for some advice

CE stands for Chinese Export, the same stuff thats imported into France.

Only if the letter spacing is right :laughing:

1 Like

Would these be of any use?

Yes but its more expensive than the one I showed earlier EDIT: the same unit is available elsewhere for much less so your choice and you may need to keep a supply of BS1362 fuses on hand as these do degrade with heat over time.

I must admit the “boost” switch as found by John looks just the ticket for Colin’s requirements but I can’t find anything similar on the French market - I guess everyone just uses Heures Creuses and a JN switch.

I would wire it in parallel with a time switch (or the EDF Heures Creuses switch) controlling a JN switch to get the best of both worlds. The fact that it is just connected to low current control wiring means it could go anywhere as long as you can run the cable.

I think if you are turning the immersion heater on and off you need to be sure the water reaches at least 50c otherwise you’ll have bacteria growing in your tank if it’s just warm all the time.
In extreme cases you can get legionnaires disease.

60c+ is the min in france but that said if it reached that temp before and this is a boost temp it will be fine.
You can still get legionnaires disease at the tap or shower head from the aerosol droplets, legionella loves to hide in limescale.

1 Like

I seem to recall that we have had the discussion about hot water cylinder temperatures elsewhere on another discussion thread.
All I will say now is that if you have ever put your hand into a flow of hot water running at 50c or above, then you will take great care never to do it again !!
There is a reason why thermostatically controlled taps have a safety stop at 38c.

We use these TimeGuard switches and am about to install 2 more on towel radiators - they are excellent - very easy to use, I like the boost facility of 1 or 2 hours at the touch of a button.

Surely a thermostatically controlled tap is a mixer.
The water is 38c when It leaves the tap.

Exactly, but upstream the requirement is to have heated the water to 60c to kill off legionella.

I have found that in general with modern mixer taps, the lever positioned in the centre of its complete range left and right delivers water at a bearable and safe temperature as is the case with the detent set on a thermo controlled shower unit. This, I am sure, is by design and benefits those with challenged vision. Our two bathrooms and the kitchen have mixer taps and all three work in this way as I have also found they do in hospital wash rooms and other public access places.

Yes, a thermostatically controlled tap is a mixer tap, but a mixer tap is not necessarily thermostatically controlled. There is a distinct difference between the two types of tap.

1 Like

There is a regulation in France that the max temperature delivered at the outlet is from memory is 42c but apart from the above mentioned hospitals and public spaces I haven’t found people following it.
Also mixer taps have the cold water exit from the outer stream as a scald prevention idea

Many French brand time switches will be single pole too. The double pole requirement is for the actual disjoncteur that supplies the chauffe eau power.

I’ve never come across a domestic chauffe eau that would be “unsafe” fed via a 16A disjoncteur or switch as 3kW is the largest element in general use i.e. 13 Amps. The vast majority of French cylinders are less than that.

1 Like

Understood thanks Jonathan. I could see from the wiring schematic how the French wire them.

So would the one from my original post work ok then.

Yes, in retrospect I think that you are right - I thought higher capacity ones might be more but some searching did not turn anything with greater than a 3kW heater.

Thanks - I suspect it would take a lifetime going through NF 1500 to figure that out.

But, actually, I think I’d still do what I suggested earlier - have both a time switch and the boost switch wired in parallel and switching the immersion via a JN switch - that way if you ever want to switch to an Heures Creuses tariff it is straightforward and you can set the timer to make sure you have hot water in the morning, but still use the boost if you have guests - and site it somewhere convenient without worrying about running long high current circuits.

Yes, but has the disadvantage of not having any battery backup for it to keep time if you have a power cut i.e. it could end up being very wrong if you don’t check on it after any power outages. The digital ones are better in this respect as they can remain autonomous for a very long time in the event of no mains power.

1 Like