Instant hot water heater

[Marcelliere]

I'm currently converting our attic space and putting in an additional bathroom.

Our plumber wanted to put in a 100-200l hot water tank to supply the shower etc.  I'd seen a Triton "chauffe eau electrique instantane" in BricoMarche (I think) which you can put under the sink (saving on space etc) and according to the brochure/phamplet, also supplied the shower and suggested this.  Mr Plumber not very keen on this idea, not least as it needs a 32A supply.

Has anyone had experience of these types of water heater?  Apart from the space saving, are they worth it and do they do the job?

The current hot water is at the other side of the house and not really practical bringing that through (holes in walls, bigger tank, etc).  Cold water no problem (obviously).

Any comments appreciated.

Regards,

[Nick Trollope]

The problem with these electric hot water heaters is the amount of electricity they need. To get a good shower, you will need a 10Kw heater, which your house supply is unlikely to have spare. It would certainly need a 6mmSq feed all the way back to the tableau (consumer unit).

They are not very popular in France (in domestic installations) for this reason.

For a single SDD, I would install a 100L chauffe-eau - cheaper and more reliable.

 

[Marcelliere]

Thanks for that.

Are these okay if you just wanted hot water for a sink though (taking into consideration the power requirements)?

Regards,

[Steve Last]

To add to this question, I've been thinking of using one of these under the sink because although we have a good size tank, we have a very long run to the tap and have to run off a huge amount of water to get some hot through to the sink. What's wrtong with supplying the instant heater with this HOT supply? Presumably hte heater turns off on a thermostat? Must be some reason why something so simple can't be done!

Steve L 

[Gyn_Paul]

[quote user="Slast"]

To add to this question, I've been thinking of

using one of these under the sink because although we have a good size

tank, we have a very long run to the tap and have to run off a huge

amount of water to get some hot through to the sink. What's wrtong with

supplying the instant heater with this HOT supply? Presumably

hte heater turns off on a thermostat? Must be some reason why

something so simple can't be done!

Steve L 

[/quote]

If you feed an instant heater with this hot, then you're not much

better off, you're still heating the cold in the pipe to use, and

allowing all that length of pipe with the hot to go cold again (£££).

Plus when the hot hits the element in the heater, it will simply trip

the overheat safety thingumy.

What you need here is a little 30L water heater on the wall (or under

the sink) supplied with mains cold, connected to the hot tap. unless

you're doing a spring clean or something, 30L is enough for kitchen

sink use. They need a standard 20A feed, and can be fitted without a

groupe de securite (although you'd be better off with one). And re-heat from cold in about 10 minutes.

p

[Gyn_Paul]

[quote user="Marcelliere"]I'm currently converting our attic space and putting in an additional bathroom.

Our

plumber wanted to put in a 100-200l hot water tank to supply the shower

etc.  I'd seen a Triton "chauffe eau electrique instantane" in

BricoMarche (I think) which you can put under the sink (saving on space

etc) and according to the brochure/phamplet, also supplied the shower

and suggested this.  Mr Plumber not very keen on this idea, not

least as it needs a 32A supply.

Has anyone had experience of these

types of water heater?  Apart from the space saving, are they

worth it and do they do the job?

The current hot water is at the

other side of the house and not really practical bringing that through

(holes in walls, bigger tank, etc).  Cold water no problem

(obviously).

Any comments appreciated.

Regards,

[/quote]

Points against:

• High capital cost
• Poor flow - (the same as a puny UK electric shower)
• The high current demand will probably mean you having to move up to the next power band = higher monthly abonnement.
• That expensive 32A feed (have you seen the price of fat cable recently ???)
• No water in a power cut (may not be an issue for you).

• no chance to benefit from cheap-rate electricity (unless you wash a lot of dishes and shower in the middle of the night).

Points for:

• small size

Really, unless space is a megga issue, it's a no-brainer: go to Bricco Depot and get a 200L chauffeau for 100-odd Euros.

p