90's Flat electric Water Heating System

[bugsyuk]

Hi all,

I'm looking for a bit of advice on a new installation. I've gotten fed up with my current set up after this winter's bills.

I'm on economy 7, with a stupidly huge tank with immersion & booster in a 2 bedroomed ground floor flat. The cold pressure is really really excellent, but the hot from the tank is pretty low, but im not overly fussed if im chaning it anyway (might just need adjusting). We just seem to be boiling the tank of water every day for no real reason which seems a waste! Space is at a premium too, currently 1/4th of my bathroom is taken up with this tank. The hot water serves 1 bathroom sink, 1 kitchen sink and a bath that doesn't get used that often at all. I have a separate 7.5kw electric shower on the mains. All my space heating is done currently by two large 80's dimplex storad heaters for a lounge and hall (looking to replace), and two newly installed Dimplex EPX 1200w panels in each bedroom (these helped with reducing bills a bit this year!).

I'm thinking of ditching the economy 7 and going for a different tarrif. As during the winter we always find we need to turn things on in the day anyway, our peak use being showers in the morning and food cooking (with usualy about 3 hours of storage heater charge a night on average in winter)

So... with a bathroom refit I want to claw some space back and ditch the tank*. From research so far I think i want to go down the route of an un-vented instant water heater, that is small enough to fit under a counter top. This would then provide the hot water for the nearby sink/new shower/occasionally bath use and the kitchen sink (no more than a 4 meter run away). I not fussed by the wait for the hot to come through, or taking a bit longer to fill a bath once a month.

I've looked at a few posts on here but I'm curious to see what your comments are on this set up, and if I am 'stupid' to consider ditching the tank... I realise it does give the possibility of a future upgrade to a wet c/h system. The two large dimplex storage heaters are on their last legs and i doubt they are very efficient anymore, ones controls are totaly buggered. If I replaced these, which i would have to consider anyway with changing from E7... then purhaps it would be better to go for a combined system.

Would my money be better spent just going the whole hog and upgrading everything to a wet c/h with some kind of combi... would it still be possible to make the space savings as above?

Thanks all!

 

[muggles]

Changing to an unvented instant water heater under your counter top won't take "a bit longer" to fill your bath, it'll take so long you'll probably give up using it at all. The most powerful domestic ones, which require a dedicated electric supply to be installed back to the fuse board, put out six litres per minute, a typical bath uses about 80 litres which means it's going to take nearly 15 minutes to run the bath, and longer in winter as the incoming main will be colder.

If you can afford it I'd say lose the old hot water cylinder and all the night storage heaters, and get yourself a decent wet c/h system, it'll be much cheaper to run and much more controllable too. A combi boiler would be your best option, obviously you would still need to find somewhere to put it but most of the time an unobtrusive location can be found. Do you have any spare wall space in your kitchen, for example?

 

[bugsyuk]

Muggles, thanks for the reply.

I was thinking of going the large domestic route, with a dedicated power supply for the instant. But Your right, I hadn't realised the flow rate would be *that* low.. although if i timed it.. it probably takes at least 10mins to fill a bath currently anyway.

Space is pretty limited everywhere, even all walls are used in the kitchen.. i dont have a freezer at the moment as getting one will mean loosing another cupboard!

I could easily build a combi into the new bathroom set up, but all the ones I have found so far seem to be pretty massive.. or at least tall, coming in at around 1500mm in height. (bit better than the current tank at least). Do you know of any that are smaller yet can pack the punch? I know the size depends on the load etc...

Cheers for the feedback

 

[muggles]

Not yet come across a combi that tall, which ones are you looking at? I assume you're looking at gas and not electric... Gas combi will be about 750mm high

 

[bugsyuk]

Ah, nopes! Sorry Muggles, its electric, as I only have that option here.

I was just having a look at this for example, the smallest ive seen so far without paying attention to wattage:

Heatrae Sadia Electromax 9kW Electric Combi Boiler

[/url]