What is the most powerful shower i can install using a combi

[stujamuk]

Hi, Im just buying my first house/flat and we are going to completely re-do the plumbing as the house needs updating.

I want to fit a really powerful shower but we dont have the space for a tank and therefore having a power shower with a pump is out.

What is my best option for using with a combi boiler?

Any advice much appreciated

Cheers

 

[ChrisR]

Depends on your mains water pressure and flow, and the power of the combi.
If you divide the kW of the combi by about 3 that gives you the flow you'll get at showering temperature in llitres/min.
Combis go from 24kW upwards, as far as you like in theory, though the biggest ones by common mfrs are about 37 - 42kW.

 

[stujamuk]

Depends on your mains water pressure and flow, and the power of the combi.
If you divide the kW of the combi by about 3 that gives you the flow you'll get at showering temperature in llitres/min.
Combis go from 24kW upwards, as far as you like in theory, though the biggest ones by common mfrs are about 37 - 42kW.

Thanks, so its going to be quite a bit down to the flow of the boiler I get, bigger the kW bigger the flow.

How powerful can a combi shower be in comparison to a real power shower? At present we have an electric shower and its useless in my opinion but is probably pretty standard.

 

[thebathroomdoctor]

Its a little bit of a catch 22.
Any thermostatic or manual shower valve will only be as good as your combi's flow, where as an electric shower will be as powerful as the kilowat rating of the electric shower. (10.5kw being the best)

If you opt for a valve, make sure its thermostatic, as it will prevent you getting scolded or froze when someone turns a tap on!!
I hope this helps...

 

[stujamuk]

Its a little bit of a catch 22.
Any thermostatic or manual shower valve will only be as good as your combi's flow, where as an electric shower will be as powerful as the kilowat rating of the electric shower. (10.5kw being the best)

If you opt for a valve, make sure its thermostatic, as it will prevent you getting scolded or froze when someone turns a tap on!!
I hope this helps...

has anyone designed an electric power shower?

Does an electric shower still have the same issues with flow rate or are there some pumped systems to boost to a set flow?

 

[Terrywookfit]

has anyone designed an electric power shower?

All power showers are electric!

Without it the pump would not operate!!

 

[thebathroomdoctor]

The answer is yes.
There is a pumped electric shower on the market.
Its called an Elite ST and is made by Mira.
It is suitable for low pressure stored water and has an integral pump to accelerate the pressure.
It retails at around...£398 in white.
Expensive, but unique.
I hope this helps.

 

[stujamuk]

The answer is yes.
There is a pumped electric shower on the market.
Its called an Elite ST and is made by Mira.
It is suitable for low pressure stored water and has an integral pump to accelerate the pressure.
It retails at around...£398 in white.
Expensive, but unique.
I hope this helps.

Many thanks, this sounds good I will look into it, may be a better option.

Cheers everyone

 

[mikej2005]

Many thanks, this sounds good I will look into it, may be a better option.

Cheers everyone

One of the advantages of a combi boiler is that you can get rid of the cold water tank in the loft (if your bathrooms are mains-fed). If you get a shower like that, then you'd have to keep it.

http://www.mirashowers.com/onlinecatalog/shower_features.jsp?item=373316&prod_num=Elite+ST

I've not come across these before, so I'm curious. At 9.8kW, will it really give a more powerful shower than, for example, a conventional 10.8kW electric shower connected to mains CW ? It's only going to have a limited capacity to heat the water and surely this will dictate how much it can push out ?

I guess if your incoming mains CW pressure/flow is poor then it might, but I can't see it coming anywhere near to power shower-type performance ?

 

[JPC]

i have to agree.
for v.poor pressure areas taking a feed from a tank might boost it some...but mostly i cant see it performing any better than the same but mains fed.
its still got to heat a set amount of water per minute, and whether its pumped or mains it will still only manage a 35* temp rise etc etc per minute

 

[Artisan Bathrooms]

Electric showers are designed to take a mains cold water supply. They are weedy because they only have 10.8kw max to put into heating the water (1/3 of a half reasonable combi). If the mains pressure is insufficient to supply an electric shower, or if mains is inaccessible, then pumped electric showers are available that are supplied by header tank. They will still only offer a crap shower as they are exactly the same type of (very small) instantaneous water heater, just with a pump to boost incoming pressure equivalent to that of ok mains.

If you want a decent shower then your best option is via stored hot water, either an open vented system boosted by a pump, or an unvented (mains pressure) system. If you don't have anywhere to put a cylinder you'll find you will get a perfectly good shower from a good combi - certainly far better than any electric shower...

 

[Doctor Drivel]

Depends on your mains water pressure and flow, and the power of the combi.
If you divide the kW of the combi by about 3 that gives you the flow you'll get at showering temperature in llitres/min.
Combis go from 24kW upwards, as far as you like in theory, though the biggest ones by common mfrs are about 37 - 42kW.

The Ethos is 54kW and the MAN is about the same. And they pour out the flowrates.

 

[Doctor Drivel]

Its a little bit of a catch 22.
Any thermostatic or manual shower valve will only be as good as your combi's flow, where as an electric shower will be as powerful as the kilowat rating of the electric shower. (10.5kw being the best)

If you opt for a valve, make sure its thermostatic, as it will prevent you getting scolded or froze when someone turns a tap on!!
I hope this helps...

That does not help. He needs a mixer with an integral pressure equalisation valve - combi compatible. With combis thermostatic mixers are not much good, as the combi regulates the temperature.

 

[Doctor Drivel]

The answer is yes.
There is a pumped electric shower on the market.
Its called an Elite ST and is made by Mira.
It is suitable for low pressure stored water and has an integral pump to accelerate the pressure.
It retails at around...£398 in white.
Expensive, but unique.
I hope this helps.

Many thanks, this sounds good I will look into it, may be a better option.

It isn't good. It has a pump so can't run off the mains.

 

[Doctor Drivel]

If you want a decent shower then your best option is via stored hot water,

It isn't. A combi will give a fabulous shower depending on mains pressure/flow.

either an open vented system boosted by a pump, or an unvented (mains pressure) system.

or a heat bank.

If you don't have anywhere to put a cylinder you'll find you will get a perfectly good shower from a good combi - certainly far better than any electric shower...

Combis deliver.