Further to my shower room installation, I am at the point of purchasing
a mixer shower.

The Aqualisa unit in the main bathroom is pump fed from the cisterns so
doesn't teach me much about selecting something suitable for a gas
combi/mains at up to 5 bar.

Most shower head performance is quoted at 0.1 bar so unhelpful.

Where does one start? The combi (25kW) will also feed the kitchen hot
tap and CH so thermostatic control might be wise.
--
Tim Lamb

On Sun, 4 Nov 2012 11:56:50 +0000, Tim Lamb
wrote:

Further to my shower room installation, I am at the point of purchasing
a mixer shower.

The Aqualisa unit in the main bathroom is pump fed from the cisterns so
doesn't teach me much about selecting something suitable for a gas
combi/mains at up to 5 bar.

Most shower head performance is quoted at 0.1 bar so unhelpful.

Where does one start? The combi (25kW) will also feed the kitchen hot
tap and CH so thermostatic control might be wise.

What about the budget? As I discovered when selecting shower kit
recently, there is a wide range of stuff available for a very wide
price range.
--
rbel

"Tim Lamb" wrote in message
...
Further to my shower room installation, I am at the point of purchasing a
mixer shower.

The Aqualisa unit in the main bathroom is pump fed from the cisterns so
doesn't teach me much about selecting something suitable for a gas
combi/mains at up to 5 bar.

Most shower head performance is quoted at 0.1 bar so unhelpful.

Where does one start? The combi (25kW) will also feed the kitchen hot tap
and CH so thermostatic control might be wise.


I ended up with two Triton showers bought online with the intention of being
able to run both at the same time off our 38kW combi.
The details for the Triton showers in the booklet from Grahams gives far
more information than you get almost anywhere else including maximum flow
rates with and without the flow limiter.
Blurb from most other plumbers tell you naff all.

What you really need is the maximum flow rate for hot water for your combi,
and the minimum flow rate for the shower mixer to work.
Oh, and a reasonable idea of how good your cold supply is.

In practice I suspect that you will be fine with almost any shower, but you
may not be able to drive the biggest round shower heads designed to simulate
a rainstorm.

HTH

Dave R
--
No plan survives contact with the enemy.
[Not even bunny]

Helmuth von Moltke the Elder

(\__/)
(='.'=)
(")_(")

In message ,
lid writes
On Sun, 4 Nov 2012 11:56:50 +0000, Tim Lamb
wrote:

Further to my shower room installation, I am at the point of purchasing
a mixer shower.

The Aqualisa unit in the main bathroom is pump fed from the cisterns so
doesn't teach me much about selecting something suitable for a gas
combi/mains at up to 5 bar.

Most shower head performance is quoted at 0.1 bar so unhelpful.

Where does one start? The combi (25kW) will also feed the kitchen hot
tap and CH so thermostatic control might be wise.

What about the budget? As I discovered when selecting shower kit
recently, there is a wide range of stuff available for a very wide
price range.
--
100-200?

I think a suitable flow could be measured using the existing at what I
think is a reasonable rate. Jug and waterproof watch:-)

Manufacturers sites, rather than the on-line outlets, seem fairly
informative.

I have studied the Wiki, thanks John, and think the installation of a
bar shower mixer looks within my capability.

Now need any *gotchas*....

--
Tim Lamb

On Sun, 4 Nov 2012 17:39:52 +0000, Tim Lamb
wrote:


Where does one start? The combi (25kW) will also feed the kitchen hot
tap and CH so thermostatic control might be wise.

What about the budget? As I discovered when selecting shower kit
recently, there is a wide range of stuff available for a very wide
price range.
--
100-200?

I think a suitable flow could be measured using the existing at what I
think is a reasonable rate. Jug and waterproof watch:-)

Manufacturers sites, rather than the on-line outlets, seem fairly
informative.

I have studied the Wiki, thanks John, and think the installation of a
bar shower mixer looks within my capability.

Now need any *gotchas*....

According to the book our WB 30CDi produces 12.6 l/min at 35C and this
is good with a decent Mira thermostatic valved shower unit.

When we started looking the advice I had from the fitters doing our
new boiler and pipework installation (but not the bathroom) was that
Mira was the safest bet. I first chose a Mira Mini because it was
available as an EV and relatively cheap (around ukp 100 online) then
realised that the valve centres were non-standard so future
replacement may be a problem. The heating fitters suggested Mira
Excel, which was prohibitively expensive. I then started looking at
sites such as Plumbworld and Discounted Heating and found a very good
price on a Mira Select EV at ukp 200 off Mira's price.

The perseverance paid off - the Select has proved to be excellent,
simple controls, very good flow and very good at maintaining the
chosen temperature.
--
rbel

"David WE Roberts" wrote in
:


"Tim Lamb" wrote in message
...
Further to my shower room installation, I am at the point of
purchasing a mixer shower.

The Aqualisa unit in the main bathroom is pump fed from the cisterns
so doesn't teach me much about selecting something suitable for a gas
combi/mains at up to 5 bar.

Most shower head performance is quoted at 0.1 bar so unhelpful.



Dave R

I have had a "pressure balancing Mira 415" on two combis without any
problem. Fitted same at my daughter's home - also combi. Less cost than a
thermostatic I believe.

On Sun, 04 Nov 2012 18:50:34 +0000, rbel wrote:

According to the book our WB 30CDi produces 12.6 l/min at 35C ...

Yech, you must like tepid to cool showers... 35C isn't very hot, hot
would be nearer 50C.

Perhaps you have missed the words "temperature rise" after 35C? That
would make sense with that sort of flow rate and the power of the heater.
15C mains cold up to 50C. Might struggle a bit at full flow rate in the
winter when the mains temp falls below 10C.

--
Cheers
Dave.

On Sunday, November 4, 2012 11:56:58 AM UTC, Tim Lamb wrote:


We installed a Grohe thermostatically controlled shower. We were worried that the thermostat in the shower unit might cause problems because the combi boiler (ATAG) also has a thermostat to modulate the gas burner and control the outlet tmeperature. In fact it all works fine.

I wish I had used smaller bore pipework from the boiler to the shower so as to get the shower hot more quickly.

In message ,
lid writes
On Sun, 04 Nov 2012 20:50:34 +0000 (GMT), "Dave Liquorice"
wrote:

On Sun, 04 Nov 2012 18:50:34 +0000, rbel wrote:

According to the book our WB 30CDi produces 12.6 l/min at 35C ...

Yech, you must like tepid to cool showers... 35C isn't very hot, hot
would be nearer 50C.

Perhaps you have missed the words "temperature rise" after 35C? That
would make sense with that sort of flow rate and the power of the heater.
15C mains cold up to 50C. Might struggle a bit at full flow rate in the
winter when the mains temp falls below 10C.

I did indeed, apologies. The showers maximum output temperature is
set at the default setting 41C which we find to be comfortable. Mira's
recommended range is 35 to 43. I have just measured the temperature
and flow at the shower head at our preferred setting and it is
currently 10 l/min at 40C.

I see I have understated my boiler o/p. Actually 9-35kW. Delta T =35K
gives 14.0l

I have yet to do the shower test:-)

--
Tim Lamb

In message ,
RobertL writes
On Sunday, November 4, 2012 11:56:58 AM UTC, Tim Lamb wrote:


We installed a Grohe thermostatically controlled shower. We were
worried that the thermostat in the shower unit might cause problems
because the combi boiler (ATAG) also has a thermostat to modulate the
gas burner and control the outlet tmeperature. In fact it all works fine.

I wish I had used smaller bore pipework from the boiler to the shower
so as to get the shower hot more quickly.

Mine will be 15mm all the way.

--
Tim Lamb