Thoughts on electric showers ...

[Madrab]

1.5mm² or even 1mm² (which should only be used for lights) are more than adequate for a 2kw load.You could actually wire up a 3kw immersion heater in 1.5mm².

Yup, even in it's worst rated application 1mm2 t&e can take up to 10 odd amps if I remember rightly. Adding to that I'm sure a lot of domestic light switches you get are rated @ 10A too these days. Wouldn't be the recommended approach though TBH.

One for the leccy guys I reckon .... @EFLImpudence ?

 

[wundaboy]

To @jonbey I'd say the best and easiest solution for you is to stick with what you have and replace your existing hot water tank with a larger capacity one. Much more straightforward solution than replacing existing showers with electric ones.

If you do go for an electric shower, there's nothing better than this - I fitted one for myself a year or so ago, and even in the depths of winter when I installed it I was really impressed with its performance. You would of course also need sufficient spare capacity on the electricity mains supply, 45/50a switchgear, 10mm2 cable as well as sufficient pressure and flow on your mains cold water supply.

 

[Vicario]

Yes, the Mira Sport range is excellent. Bear in mind that a 10.8kw shower will pull nearly 50 amps so your electrics will need to be able to cope. If you have a 60amp main fuse and have a electric oven or/and an induction hob or if you use a lot of fan heaters etc. you'll need to upgrade to 80 or 100 amp.

 

[JP_]

Can you please give us a close up picture of the white box that is above the wall heater in pic 2.

One person is saying it's a light switch, I am saying it's an FCU. Can you also please tell us where that white pull cord that's hanging underneath the heater is coming from, is it from inside the fan heater?

The pull cord is part of the heater - it looks like one of these
https://www.electricalworld.com/en/...ter-With-Pull-Cord-and-Thermostat/m-1040.aspx

 

[JP_]

Is the Cold water from a TANK , Electric showers usually need to have a mains pressure to operate - Do you have mains cold water supply in the bathroom OR is it feed from a TANK - and also 0.1Bar pressure ?

The spec for the screwfix shower is MIN 1.5bar pressure
The wickes one only says -

• Suitable for cold mains only

and does not give the min pressure

That's the existing normal shower, fed with hot water from tank at 0.1bar and cold water from storage tank - the new shower was set up same way, and all working OK.
Mains water is high pressure, not measured it, but I can tell it's pretty good (plus a neighbour has electric shower and has not complained)

 

[Madrab]

Thanks for that @jonbey and I do apologise for having to take this off post a little to confirm some information.

disagree, it’s clearly switched via a 6amp light switch above it. which may or may not be fed via the pullcord as you suggest . unless it’s a shower pullcord then we can assume it’s on the lighting circuit fed by a 1.5 or even 1mm cable on a 6 amp circuit breaker.
not suitable for 1kw let alone 2

It's not a 6A light switch - it's an FCU sitting on a 20A radial. It's not a light pull switch, the heater is fed by it's own factory fitted cable switched on and off via it's own internal corded pull switch, which is normal for a fan heater that is IP designed for use in a wet space, it's so someone won't come into wet contact with a switch and is more than acceptable.

As far as cable capacities are concerned I think you want to go and do a bit more investigation about standard T&E current carrying limits, you may be surprised. 1mm2 is quite capable of carrying the 8 odd amps that a 2Kw heater could draw.

 

[Madrab]

Back to the shower ..... Mira's are excellent electric showers, the issue with electric showers is in the winter when the incoming water is much colder so it's harder for the shower to heat. How it does that is it slows the incoming water to give it the time to heat. A 10.5Kw tries to offset that a bit by it's higher rated heater tank.

Electric shower do the job but it won't be a skin tingling, blasting shower .... as long as you're happy with that then they do the job fine.

 

[dontbelieveawordofit]

1mm2 is quite capable of carrying the 8 odd amps that a 2Kw heater could draw.

the point being at 240v a 2kw heater draws over 9amps.
a 1mm cable carries 8 amps.
and the breaker in any event shouldn’t exceed 16a
my aoplogies for mistaking the fcu for a normal plate switch.