More ponderings on the bathroom install/refit front.

The new ensuite we are planning will have longer pipes runs from the
HW cylinder than the current main bathroom, which takes ages it seems.

(House is an L shape, kitchen/utility on one leg, with the HW tank
above and just a bit along from the kitchen in a room which is
technically a bathroom, but not used as such - though is to be refitted
and used again. The ensuite and current house bathroom, are on the
other bit of the L . If I was starting from scratch no I wouldn't start
from here, but i'm not, so I am)

So, considering putting an additional HW cylinder for the ensuite.

Going for a bit of luxury, (the room is much bigger than ur old bathrrom
in the old house) We will have a decent pumped shower (no, I'm not
interested in a electric shower), and a nice big bath (I like having the
space for a proper ). So maximum draw in normal use is likely to be a
couple of consecutive showers, or a bath fill.

How big a tank do you reckon for this? My gut feeling is that the
marginal cost of a bigger tank, or heating a bit more water is such that
erring on the bigger side is a good idea.

Space for the tank is not an issue, we ahve a cupboard in the room with
planty of space
--
Chris French

In message , John
Rumm writes
On 08/11/2010 13:16, chris French wrote:

How big a tank do you reckon for this? My gut feeling is that the
marginal cost of a bigger tank, or heating a bit more water is such that
erring on the bigger side is a good idea.

Space for the tank is not an issue, we ahve a cupboard in the room with
planty of space

A big part of the question is how often will it be reheated (and by what)?

What sort of boiler have you got? If its a modern condenser, can it
support dual (or more) temperature operation? Ideally you want a boiler
that can run a lower flow temp for the rads to improve efficiency, but
then ramp up the temperature for the final stages of hot water heating.

With simple fixed output temperature boilers, there is no harm in
having the water reheated by its stat on demand, meaning you can cope
with a smaller tank. If however you need to arrange set aside times for
reheating when there is likely to be less demand for room heating, then
its handy to go for more storage (i.e. 250L or more).


Thanks John,

The boiler is a gas fired, floor standing, conventional flue, Ideal
Mexico. I don't have the documentation handy (it was in the house when
we bought it), but ISTR it is about 10 - 15 years old. There aren't
plans to replace it at the moment.

A heat loss calculation for the heating system is on list of round
tuits, but AFAICT there is enough capacity to supply the HW at the same
time as the heating. Currently we have a 165 -ish L HW cylinder on a
gravity fed circuit from the boiler. That will all get upgraded to
pumped of course. The route for the primary circuit to the new cylinder
will be a bit convoluted, but doable.

so I guess sizing to fill the bath as a minimum is a place to start,
what sort of percentage of water will come from the tank (say at 60 C)
to run a nice hot bath?
--
Chris French

On 08/11/2010 13:16, chris French wrote:

How big a tank do you reckon for this? My gut feeling is that the
marginal cost of a bigger tank, or heating a bit more water is such that
erring on the bigger side is a good idea.

Depends whether you have teenagers in the house, or are likely to do so
soon.

Problem is that once the discover the concept of 'washing', they then go
in the shower and stand there until the hot tank runs cold. It's a
physical impossibilty to find a tank big enough to outlast them, which
means that the bigger the tank you install, the more hot water you will
waste. And there'll still be none for your own shower.

hth
David

In message , Lobster
writes
On 08/11/2010 13:16, chris French wrote:

How big a tank do you reckon for this? My gut feeling is that the
marginal cost of a bigger tank, or heating a bit more water is such that
erring on the bigger side is a good idea.

Depends whether you have teenagers in the house, or are likely to do so
soon.

Problem is that once the discover the concept of 'washing', they then
go in the shower and stand there until the hot tank runs cold. It's a
physical impossibilty to find a tank big enough to outlast them, which
means that the bigger the tank you install, the more hot water you will
waste. And there'll still be none for your own shower.

No teenagers yet, but they will morph sooner or later.

But this tank is for our ensuite, no kids allowed :-)
--
Chris French

In message , Doctor Drivel
writes

"chris French" wrote in message
news
In message , John
Rumm writes
On 08/11/2010 13:16, chris French wrote:

How big a tank do you reckon for this? My gut feeling is that the
marginal cost of a bigger tank, or heating a bit more water is such that
erring on the bigger side is a good idea.

Space for the tank is not an issue, we ahve a cupboard in the room with
planty of space

A big part of the question is how often will it be reheated (and by what)?



The boiler is a gas fired, floor standing, conventional flue, Ideal
Mexico. I don't have the documentation handy (it was in the house when
we bought it), but ISTR it is about 10 - 15 years old. There aren't
plans to replace it at the moment.

A heat loss calculation for the heating system is on list of round
tuits, but AFAICT there is enough capacity to supply the HW at the
same time as the heating. Currently we have a 165 -ish L HW
cylinder on a gravity fed circuit from the boiler. That will all get
upgraded to pumped of course. The route for the primary circuit to
the new cylinder will be a bit convoluted, but doable.


Depends on the house layout, but if there is room for a combi near the
bathroom put one in. Do not connect up the CH and do that later when a
the old gas guzzling Mexico is ditched. Later you could again fit
another combi at the other end of the "L".

Then re-arrange to have one combi do upstairs CH and one bathroom, one
do downstairs and the other bathroom. Combis are cheap and easy. They
do not run out of hot water.


I did think about something like that - though using a gas instant water
heater rather than a combi. But the bath filling performance of combi's
is poor.

One of the frustrations of the current bathroom is the poor filling
performance of the bath. This is from the tank, but was badly done. It's
a fairly convoluted pipe run, and done in 15mm pipe and it just can't
supply water faster enough (and if you decide to wash your hands in the
handbasin or something whilst running it, you get an airlock in the bath
supply). The bath in the old bathroom that we don't really use much
fills much faster as it's near the cylinder and plumbed in 22mm.

Anyway BTDTGTTS I fitted one in the old house, it was an acceptable
compromise there for space reasons, but I much prefer a storage system.
I'm not convinced our flow rate from that mains is that great either.
They aren't cheap AFAIC, esp as this time it would probably be a
plumber install, and getting gas up there would be non-trivial. I don't
forsee running out of water to be an issue in normal use.

You could fit an insulated secondary circulation loop. It could be
activated by a PIR and turn on the pump only when someone is in the
en-suit. This prevents heating the house with the loop unnecessarily if
running all day.

That is the other idea that bobs around. I'd have to upgrade the
existing cylinder to a bigger one though as it's quite easy for us to
use up all the HW at the moment.

You could fit an instant electric heater in the new bathroom at the
basin fed from the cylinder, so it cuts out when hot water comes
through. The shower and bath do not matter as you get undressed after
turning on. The en-suite will not be used as much as the main
bathroom, so high electric bills are not a worry.


This just feels like a bit of a kludge really.

Two cylinders will take up space and add to control complexity -
valves, etc.


As I said, space isn't really an issue (and a combi would take up space
as well, and the cupboard would not be such a good space for it.), we
have a big cupboard that can be used, and it will give us a nice airing
cupboard by our bedroom. I don't really see the controls ( a timer and a
valve) as anything complicated, certainly not compared to having two
boilers for the CH :-)
--
Chris French

"Doctor Drivel" wrote in
:


"chris French" wrote in message
...
In message , Doctor Drivel
writes

"chris French" wrote in message
news In message ,
John Rumm writes
On 08/11/2010 13:16, chris French wrote:

How big a tank do you reckon for this? My gut feeling is that the
marginal cost of a bigger tank, or heating a bit more water is
such that
erring on the bigger side is a good idea.

Space for the tank is not an issue, we ahve a cupboard in the
room with
planty of space

A big part of the question is how often will it be reheated (and by
what)?



The boiler is a gas fired, floor standing, conventional flue, Ideal
Mexico. I don't have the documentation handy (it was in the house
when we bought it), but ISTR it is about 10 - 15 years old. There
aren't plans to replace it at the moment.

A heat loss calculation for the heating system is on list of round
tuits, but AFAICT there is enough capacity to supply the HW at the
same time as the heating. Currently we have a 165 -ish L HW
cylinder on a gravity fed circuit from the boiler. That will all
get upgraded to pumped of course. The route for the primary
circuit to the new cylinder will be a bit convoluted, but doable.


Depends on the house layout, but if there is room for a combi near
the bathroom put one in. Do not connect up the CH and do that later
when a the old gas guzzling Mexico is ditched. Later you could again
fit another combi at the other end of the "L".

Then re-arrange to have one combi do upstairs CH and one bathroom,
one do downstairs and the other bathroom. Combis are cheap and easy.
They do not run out of hot water.


I did think about something like that - though using a gas instant
water heater rather than a combi. But the bath filling performance
of combi's is poor.

It depends on the model and flow rate. High flowrate combis are very
good. I am on about minimum 35kW.

Anyway BTDTGTTS I fitted one in the old house, it was an acceptable
compromise there for space reasons, but I much prefer a storage
system. I'm not convinced our flow rate from that mains is that
great either.

You have to measure the flowrate and pressure of the mains pipe.

They aren't cheap AFAIC, esp as this time it would probably be a
plumber install, and getting gas up there would be non-trivial. I
don't forsee running out of water to be an issue in normal use.

You could fit an insulated secondary circulation loop. It could be
activated by a PIR and turn on the pump only when someone is in the
en-suit. This prevents heating the house with the loop unnecessarily
if running all day.

That is the other idea that bobs around. I'd have to upgrade the
existing cylinder to a bigger one though as it's quite easy for us to
use up all the HW at the moment.

You could fit an instant electric heater in the new bathroom at the

one boiler and


What?

Not two combies this time?


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"Doctor Drivel" wrote in
:


"Heliotrope Smith" wrote in message
.121...
"Doctor Drivel" wrote in
:


"chris French" wrote in message
...
In message , Doctor Drivel
writes

"chris French" wrote in message
news In message ,
John Rumm writes
On 08/11/2010 13:16, chris French wrote:

How big a tank do you reckon for this? My gut feeling is that
the marginal cost of a bigger tank, or heating a bit more water
is such that
erring on the bigger side is a good idea.

Space for the tank is not an issue, we ahve a cupboard in the
room with
planty of space

A big part of the question is how often will it be reheated (and
by what)?



The boiler is a gas fired, floor standing, conventional flue,
Ideal Mexico. I don't have the documentation handy (it was in the
house when we bought it), but ISTR it is about 10 - 15 years
old. There aren't plans to replace it at the moment.

A heat loss calculation for the heating system is on list of
round tuits, but AFAICT there is enough capacity to supply the
HW at the same time as the heating. Currently we have a 165
-ish L HW cylinder on a gravity fed circuit from the boiler.
That will all get upgraded to pumped of course. The route for
the primary circuit to the new cylinder will be a bit
convoluted, but doable.


Depends on the house layout, but if there is room for a combi near
the bathroom put one in. Do not connect up the CH and do that
later when a the old gas guzzling Mexico is ditched. Later you
could again fit another combi at the other end of the "L".

Then re-arrange to have one combi do upstairs CH and one bathroom,
one do downstairs and the other bathroom. Combis are cheap and
easy. They do not run out of hot water.


I did think about something like that - though using a gas instant
water heater rather than a combi. But the bath filling performance
of combi's is poor.

What?

Not two combies this time?

Two boilers were mentioned


Mmmmmmmmmmmmm, Which two boilers are you refering to?????
Do you not stop to think before putting your foot in your mouth?
What a F------g ****. LOL, LOL

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