Using an electric shower and combi boiler as a team to save energy!?
 

I am getting close to the first fix of renovating my house and wanted
to test out an idea I have been thinking about on the plumbing side of
things.

These are the two main unchangeable factors I have already decided upon

1) I am going to have a new decent combi condensing boiler
2) I will be having 2 showers. One in the main bathroom and the other
in an en suite.

So the obvious problem is that when both showers are in use at the same
time one will suffer for sure.

First Solution - Replace one thermostatic shower with an electric
shower. But more costly at say 3/4 times more per electric shower use.

Second Solution - Have thermostatic shower and an electric shower side
by side and use whichever is dictated by if the other is in use. Kind
of weird looking I imagine.

OR Supply warmed water via a mixer valve to the electric shower.

The advantage I see here is if there are no other demands on the hot
water the electric shower will be supplied by warm water (set at max
safe temp) so the electric show would only have to rise the temperature
by a small amount. But if hot water is being used elsewhere then the
electric shower will then pretty much take over heating the water..

This idea seems to worki n theory in my mind, but my knowledge of
practical plumbing is limited (this will have change as I'm going have
a go doing all the plumbing myself). One problem maybe is that I have
assumed a method/device exists that allows you to prioritise supply of
hot water to different places.

Another factor that might help me out is that I have very high mains
cold water pressure (my cheap hose pipes expand to twice there width!)
and something close to 50 liters a minute flow rate.

Using an electric shower and combi boiler as a team to save energy!?
 

Given that you want 2 strong, simultaneous, non-electric showers, what
are your reasons for not having a thermal store?

Using an electric shower and combi boiler as a team to save energy!?
 

Using an electric shower and combi boiler as a team to save energy!?
 

Ah well I have converted the Attic - and am loath to loose any space
for a hot water tank (which I assume is the thermal store?).

Also, as I am going to do the plumbing a Combi boiler seems like less
plumbing for me to get my head around.

And finally, from phoning around a load of estate agents I asked them
as to which type boiler system was thought of as better by your typical
house buyer and they said without fail combis.

But regardless of the above I would agree in a perfect world I would go
for the system you suggest. But working within my remit, what do you
think?

Using an electric shower and combi boiler as a team to save energy!?
 

MrsCabbage wrote:

Ah well I have converted the Attic - and am loath to loose any space
for a hot water tank (which I assume is the thermal store?).

Also, as I am going to do the plumbing a Combi boiler seems like less
plumbing for me to get my head around.

And finally, from phoning around a load of estate agents I asked them
as to which type boiler system was thought of as better by your typical
house buyer and they said without fail combis.

thats estate agents for you :) Combis are really better avoided on the
whole, unless you get a really high power one.

Another way to stretch your hot water further is to use a drain heat
exchanger. The warm water going down the shower drain prewarms the cold
feed to the shower, resulting in less hot water requirement

Another way to stretch it again is to put the cold feed to the hot
supply through a heat exchanger, with the other side on the CH system.
In winter this will give a significant extra quantity of hot water. In
summer it will make that incoming water a bit less cold, but thats all.
In summer people have cooler showers, so it fits quite well.


NT

Using an electric shower and combi boiler as a team to save energy!?
 

On 25 Nov 2006 05:12:06 -0800 someone who may be "MrsCabbage"
wrote this:-

Ah well I have converted the Attic - and am loath to loose any space
for a hot water tank (which I assume is the thermal store?).

http://www.google.co.uk/search?hl=en...UK%7CcountryGB
comes up with many links.

A thermal store will take some space, but it will provide a far
better hot water system. It isn't just when both showers are in use
that one will suffer, the same will happen when a tap is opened. If
there is a combination boiler that is powerful enough to avoid this
it will be large, so to some extent the difference is where the
space is taken up, rather than the amount of space taken up.

Also, as I am going to do the plumbing a Combi boiler seems like less
plumbing for me to get my head around.

Not a lot less plumbing.

A combination boiler is a single point of failure. It is usually the
hot water side that goes and one is then stuck until it is fixed.




--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

Using an electric shower and combi boiler as a team to save energy!?
 

"MrsCabbage" wrote in message
ups.com...
Ah well I have converted the Attic - and am loath to loose any space
for a hot water tank (which I assume is the thermal store?).

Also, as I am going to do the plumbing a Combi boiler seems like less
plumbing for me to get my head around.

And finally, from phoning around a load of estate agents I asked them
as to which type boiler system was thought of as better by your typical
house buyer and they said without fail combis.


Ed Sirret said something recently abouit this.

But regardless of the above I would agree in a perfect world I would go
for the system you suggest. But working within my remit, what do you
think?

See my post Rinnai. Appears the best way to go for you.

Using an electric shower and combi boiler as a team to save energy!?
 

On Sat, 25 Nov 2006 04:09:39 -0800, MrsCabbage wrote:

I am getting close to the first fix of renovating my house and wanted
to test out an idea I have been thinking about on the plumbing side of
things.

These are the two main unchangeable factors I have already decided upon

1) I am going to have a new decent combi condensing boiler
2) I will be having 2 showers. One in the main bathroom and the other
in an en suite.

So the obvious problem is that when both showers are in use at the same
time one will suffer for sure.

First Solution - Replace one thermostatic shower with an electric
shower. But more costly at say 3/4 times more per electric shower use.

An electric shower will be so poxy compared to a thermostatic one fed off
a combi no-one will want to use it.

Second Solution - Have thermostatic shower and an electric shower side
by side and use whichever is dictated by if the other is in use. Kind
of weird looking I imagine.

Even the thermostatic mixer shower contending with another off the ciombi
is still likely to beat the leccy one hands down:-)


OR Supply warmed water via a mixer valve to the electric shower.

The advantage I see here is if there are no other demands on the hot
water the electric shower will be supplied by warm water (set at max
safe temp) so the electric show would only have to rise the temperature
by a small amount. But if hot water is being used elsewhere then the
electric shower will then pretty much take over heating the water..

I don't think electric showers modulate the electric power consumption so
feeding it hot water may result in excessiveoutput temperatures and safety
thermal trips operating in the shower. Dunno ...

If you really don't want to mess with themal stores etc you could get a
combi with a bit of storage built in, which would tide you over brief
periodsof contention for hot water.

WRT to thermal stores remember they don't have to go in the attic.

Using an electric shower and combi boiler as a team to save energy!?
 

John Stumbles wrote:
On Sat, 25 Nov 2006 04:09:39 -0800, MrsCabbage wrote:

I am getting close to the first fix of renovating my house and wanted
to test out an idea I have been thinking about on the plumbing side of
things.

These are the two main unchangeable factors I have already decided upon

1) I am going to have a new decent combi condensing boiler
2) I will be having 2 showers. One in the main bathroom and the other
in an en suite.

So the obvious problem is that when both showers are in use at the same
time one will suffer for sure.

just not using both showers at once is so much simpler :)


NT

Using an electric shower and combi boiler as a team to save energy!?
 

Gosh! I switch web pages and look at the how many posts have appeared!
Thanks.

My my it appears the electric shower is well hated and I must agree the
temporary 10.5kw shower I set up over a bath (in my temporary
accomadation) only runs at 3.5 litres at a proper temperature at the
moment.

I suppose I thought if I supplied hot water to it as it would barely
have to heat it then it would have very little effect on the flow rate
from the combi so wouldn't suffer from crappy electric shower
syndrom...plus be cheaper to run.

I see your point on confusing the temperature sensor and that might
vary between showers. I think it might be easier if I just try it and
see.

Or has anyone else actually tried this in practice?

Using an electric shower and combi boiler as a team to save energy!?
 

On Sat, 25 Nov 2006 08:15:29 -0800, MrsCabbage wrote:

Or has anyone else actually tried this in practice?

If you want to try a practical experiment to see how 2 showers driven by
a combi might work in practice you could get 2 shower heads of a type you
might want to use for a decent shower, connect them up via some pushfit
valves and bits & bobs and find a friend with a regular combi and take it
round there to try out (maybe hook up to washing machine H & C outlets).

prett

H -------+-------------
| |
(X) (X) valve
| |
+-- +-- shower
| |
(X) (X) valve
| |
C -------+-------------

Using an electric shower and combi boiler as a team to save energy!?
 

"MrsCabbage" wrote in message
oups.com...
Gosh! I switch web pages and look at the how many posts have appeared!
Thanks.

My my it appears the electric shower is well hated

Just look at my posts.

Using an electric shower and combi boiler as a team to save energy!?
 

"John Stumbles" wrote in message
.. .
On Sat, 25 Nov 2006 08:15:29 -0800, MrsCabbage wrote:

Or has anyone else actually tried this in practice?

If you want to try a practical experiment to see how 2 showers driven by
a combi might work in practice you could get 2 shower heads of a type you
might want to use for a decent shower, connect them up via some pushfit
valves and bits & bobs and find a friend with a regular combi and take it
round there to try out (maybe hook up to washing machine H & C outlets).

A silly ting to do. It has been established he needs a high flow combi or
multi-point. I gave some models.

Using an electric shower and combi boiler as a team to save energy!?
 

Yup John, I think a practical experiment is called for here. Thanks
for the plan and cute little diagram!

I am lucky as I have to fit a temporary combi boiler in my tempoary
accomadation, as boiler failed last week and it is cooooold here.

I will then be able to mess about with push fit fittings and 2 thermo
showers and an electric shower to see exactly how my odd idea would
work in practice.

I will post the results of my experiments and then conjecture will melt
into fact :)

Thanks everyone for you input.

Using an electric shower and combi boiler as a team to save energy!?
 

On Sat, 25 Nov 2006 21:33:35 +0000, Doctor Drivel wrote:


"John Stumbles" wrote in message
.. .
On Sat, 25 Nov 2006 08:15:29 -0800, MrsCabbage wrote:

Or has anyone else actually tried this in practice?

If you want to try a practical experiment to see how 2 showers driven by
a combi might work in practice you could get 2 shower heads of a type you
might want to use for a decent shower, connect them up via some pushfit
valves and bits & bobs and find a friend with a regular combi and take it
round there to try out (maybe hook up to washing machine H & C outlets).

A silly ting to do. It has been established he needs a high flow combi or
multi-point. I gave some models.

So you prefer theory over practice?

Using an electric shower and combi boiler as a team to save energy!?
 

"John Stumbles" wrote in message
.. .
On Sat, 25 Nov 2006 21:33:35 +0000, Doctor Drivel wrote:


"John Stumbles" wrote in message
.. .
On Sat, 25 Nov 2006 08:15:29 -0800, MrsCabbage wrote:

Or has anyone else actually tried this in practice?

If you want to try a practical experiment to see how 2 showers driven by
a combi might work in practice you could get 2 shower heads of a type
you
might want to use for a decent shower, connect them up via some pushfit
valves and bits & bobs and find a friend with a regular combi and take
it
round there to try out (maybe hook up to washing machine H & C outlets).

A silly ting to do. It has been established he needs a high flow combi or
multi-point. I gave some models.

So you prefer theory over practice?

Read what I wrote.

Using an electric shower and combi boiler as a team to save energy!?
 

MrsCabbage wrote:

Yup John, I think a practical experiment is called for here. Thanks
for the plan and cute little diagram!

I am lucky as I have to fit a temporary combi boiler in my tempoary
accomadation, as boiler failed last week and it is cooooold here.

I will then be able to mess about with push fit fittings and 2 thermo
showers and an electric shower to see exactly how my odd idea would
work in practice.

I will post the results of my experiments and then conjecture will melt
into fact :)

Thanks everyone for you input.
I posted a query on this a long time ago.
What about a thermostatic valve set to supply the electic shower input
at a fixed temp of say, 20 to 25 degrees, something safe. It would not
nick much from the other combi shower, but allow the electric shower to
provide more hot water. It would also provide consistent electric
shower performance throughout the year. I can't see why this wouldn't
work. Or how about electric shower into thermo valve cold side, then
you could have the electric shower power up as required (flow switch ?)
and the thermo valve would start taking less hot from the combi.
Any thoughts ?
Simon.