Hi all

My daughter moved into a house a while back, which has had the boiler
replaced with one of these new fangled things that sits on the kitchen wall,
and has about a thousand pipes going up to it. No problem there - seems to
work ok.

She is now looking at replacing the bathroom suite, and good old dad is
going to get roped in to do it. Over the years, I have done much DIY
plumbing on my own houses, and would not normally have any trouble shutting
off supplies and draining down as required, to disconnect the old bath,
basin etc. However, all of my experience in plumbing, has been on what was
previously the 'conventional' indirectly heated stored hot water systems.
Now as I understand it, these new style boilers heat the water 'on the fly'
like an electric shower, or an antique geyser ??

So, my question is, what do I need to do to isolate the hot and cold feeds
to the bathroom, and does anything need to be done after connecting up to
the new suite, other than turning back on, whatever has to be turned off to
do the job ?

I have a "Part 2" question on this, related to my own installation, but that
can wait until I sort out what I'm doing here ...

TIA

Arfa

On Aug 3, 5:03*pm, "Arfa Daily" wrote:
Hi all

My daughter moved into a house a while back, which has had the boiler
replaced with one of these new fangled things that sits on the kitchen wall,
and has about a thousand pipes going up to it. No problem there - seems to
work ok.

She is now looking at replacing the bathroom suite, and good old dad is
going to get roped in to do it. Over the years, I have done much DIY
plumbing on my own houses, and would not normally have any trouble shutting
off supplies and draining down as required, to disconnect the old bath,
basin etc. However, all of my experience in plumbing, has been on what was
previously the 'conventional' indirectly heated stored hot water systems.
Now as I understand it, these new style boilers heat the water 'on the fly'
like an electric shower, or an antique geyser ??

So, my question is, what do I need to do to isolate the hot and cold feeds
to the bathroom, and does anything need to be done after connecting up to
the new suite, other than turning back on, whatever has to be turned off to
do the job ?

I have a "Part 2" question on this, related to my own installation, but that
can wait until I sort out what I'm doing here ...

TIA

Arfa

Hi Arfa,

I take it we're talking about a combi here then? As you say they heat
water straight from the mains on the fly. If you turn off the mains
water at the stopcock you will turn off hot and cold so you can
replumb bath, basin and loo quite happily. When you're done just turn
it back on again. I assume you're not planning any work on the
radiators here? That's when it gets a bit more complicated.

Cheers!

Martin

In article ,
Arfa Daily wrote:
Hi all

My daughter moved into a house a while back, which has had the boiler
replaced with one of these new fangled things that sits on the kitchen
wall, and has about a thousand pipes going up to it. No problem there -
seems to work ok.

Yes - my old boiler had only three - flow return and gas . The new has 7 -
heating f&r, hot water f&r, gas, fill/drain, condensate drain, safety over
pressure outlet.

She is now looking at replacing the bathroom suite, and good old dad is
going to get roped in to do it. Over the years, I have done much DIY
plumbing on my own houses, and would not normally have any trouble
shutting off supplies and draining down as required, to disconnect the
old bath, basin etc. However, all of my experience in plumbing, has
been on what was previously the 'conventional' indirectly heated stored
hot water systems. Now as I understand it, these new style boilers heat
the water 'on the fly' like an electric shower, or an antique geyser ??

Not necessarily. That is a combination boiler. Mine heats a storage tank
in the 'old' way. But it would be easy to find out if there is a storage
tank?

So, my question is, what do I need to do to isolate the hot and cold
feeds to the bathroom, and does anything need to be done after
connecting up to the new suite, other than turning back on, whatever
has to be turned off to do the job ?

If it is a combination boiler then the hot simply comes off the mains -
and turning that off will isolate the hot taps. I assume the cold are also
off the mains - but worth checking. Since it's mains pressure there should
be no problems with airlocks when turning on again.

I have a "Part 2" question on this, related to my own installation, but
that can wait until I sort out what I'm doing here ...

I'm waiting with baited breath...

TIA

Arfa

--
*I used to have an open mind but my brains kept falling out *

Dave Plowman London SW
To e-mail, change noise into sound.

Martin Pentreath wrote:
I assume you're not planning any work on the
radiators here? That's when it gets a bit more complicated.

?

How so? I find it easier.


--
Dave - The Medway Handyman
www.medwayhandyman.co.uk

"Martin Pentreath" wrote in message
...
On Aug 3, 5:03 pm, "Arfa Daily" wrote:
Hi all

My daughter moved into a house a while back, which has had the boiler
replaced with one of these new fangled things that sits on the kitchen
wall,
and has about a thousand pipes going up to it. No problem there - seems to
work ok.

She is now looking at replacing the bathroom suite, and good old dad is
going to get roped in to do it. Over the years, I have done much DIY
plumbing on my own houses, and would not normally have any trouble
shutting
off supplies and draining down as required, to disconnect the old bath,
basin etc. However, all of my experience in plumbing, has been on what was
previously the 'conventional' indirectly heated stored hot water systems.
Now as I understand it, these new style boilers heat the water 'on the
fly'
like an electric shower, or an antique geyser ??

So, my question is, what do I need to do to isolate the hot and cold feeds
to the bathroom, and does anything need to be done after connecting up to
the new suite, other than turning back on, whatever has to be turned off
to
do the job ?

I have a "Part 2" question on this, related to my own installation, but
that
can wait until I sort out what I'm doing here ...

TIA

Arfa

Hi Arfa,

I take it we're talking about a combi here then? As you say they heat
water straight from the mains on the fly. If you turn off the mains
water at the stopcock you will turn off hot and cold so you can
replumb bath, basin and loo quite happily. When you're done just turn
it back on again. I assume you're not planning any work on the
radiators here? That's when it gets a bit more complicated.

Cheers!

Martin

Hi Martin

Yes, I guess we are talking combi. It does the hot water and the CH. The
original storage tank has been removed from the airing cupboard, which is in
the bathroom where the new suite is going to go.

I kind of suspected from my admittedly sketchy understanding of these
boilers, that there would be no issue other than shut it off, do the work,
and turn it back on again, but I just wanted to make sure, so I did not
finish up asking what I had done wrong after doing it, to be greeted by lots
of sharp intakes of breath and "You did *what* !!??" s d;~}

Arfa

"Arfa Daily" wrote in message
...

Turn the boiler off.
Then turn the water mains off.
Do your plumbing.
Turn the mains on.
Flush the pipes by operating the taps.
Turn the boiler back on.

If you forget to turn the boiler off it may turn on and you get steam
shooting out of your cut pipe work if you are unlucky or worse if you are
very unlucky.

In an earlier contribution to this discussion,
Arfa Daily wrote:


Yes, I guess we are talking combi. It does the hot water and the CH.
The original storage tank has been removed from the airing cupboard,
which is in the bathroom where the new suite is going to go.

I kind of suspected from my admittedly sketchy understanding of these
boilers, that there would be no issue other than shut it off, do the
work, and turn it back on again, but I just wanted to make sure, so I
did not finish up asking what I had done wrong after doing it, to be
greeted by lots of sharp intakes of breath and "You did *what* !!??"
s d;~}
Arfa

How long is it going to take you to do the job? If you simply turn the water
off at the mains, you won't have any hot *or* cold water in the house -
kitchen sink, toilet(s), etc, for the duration. It may be better to cut and
blank off the water pipes where they the enter the bathroom - then you can
turn everything on again while you do the work. Bring your new pipework up
to the blanked-off bits, and turn the mains off again while making the final
connections.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

Roger Mills wrote:
In an earlier contribution to this discussion,
Arfa Daily wrote:


Yes, I guess we are talking combi. It does the hot water and the CH.
The original storage tank has been removed from the airing cupboard,
which is in the bathroom where the new suite is going to go.

I kind of suspected from my admittedly sketchy understanding of these
boilers, that there would be no issue other than shut it off, do the
work, and turn it back on again, but I just wanted to make sure, so I
did not finish up asking what I had done wrong after doing it, to be
greeted by lots of sharp intakes of breath and "You did *what* !!??"
s d;~}
Arfa

How long is it going to take you to do the job? If you simply turn
the water off at the mains, you won't have any hot *or* cold water in
the house - kitchen sink, toilet(s), etc, for the duration. It may be
better to cut and blank off the water pipes where they the enter the
bathroom - then you can turn everything on again while you do the
work. Bring your new pipework up to the blanked-off bits, and turn
the mains off again while making the final connections.

Good advice Roger, although a couple of service valves would save turning
off twice.


--
Dave - The Medway Handyman
www.medwayhandyman.co.uk

On 3 Aug, 18:11, "The Medway Handyman"
wrote:
Martin Pentreath wrote:

I assume you're not planning any work on the
radiators here? That's when it gets a bit more complicated.

?

How so? *I find it easier.

Well unless you have some handyman trick up your sleeve, breaking into
the rad circuit means draining everything down, ideally a bit of a
half-hearted flush while you've got it in that state, refilling,
runnning all round the house bleeding rads and getting nasty radiator
water on your clean magnolia walls and cream carpets, there's bound to
be an airlock or some awkward leg of pipework somewhere that won't
fill properly and gives you jip, and then you have to repressurise it
all and put inhibitor in when you're done. How can that be easier than
turning off a stopcock?? Go on, tell me the trick, freezing kits don't
count!

On 3 Aug, 18:20, "Arfa Daily" wrote:

Hi Martin

Yes, I guess we are talking combi. It does the hot water and the CH. The
original storage tank has been removed from the airing cupboard, which is in
the bathroom where the new suite is going to go.

I kind of suspected from my admittedly sketchy understanding of these
boilers, that there would be no issue other than shut it off, do the work,
and turn it back on again, but I just wanted to make sure, so I did not
finish up asking what I had done wrong after doing it, to be greeted by lots
of sharp intakes of breath and "You did *what* !!??" s * * *d;~}

Arfa

Very wise. My old dad trained as a proper lead plumber in the fifties
and regarded copper tube as the devil's own work. Combis were beyond
the pale, he refused to understand them or have anything to do with
them. God knows what he would make of pushfits!

Martin Pentreath wrote:
On 3 Aug, 18:11, "The Medway Handyman"
wrote:
Martin Pentreath wrote:

I assume you're not planning any work on the
radiators here? That's when it gets a bit more complicated.

?

How so? I find it easier.

Well unless you have some handyman trick up your sleeve, breaking into
the rad circuit means draining everything down, ideally a bit of a
half-hearted flush while you've got it in that state, refilling,
runnning all round the house bleeding rads and getting nasty radiator
water on your clean magnolia walls and cream carpets, there's bound to
be an airlock or some awkward leg of pipework somewhere that won't
fill properly and gives you jip, and then you have to repressurise it
all and put inhibitor in when you're done. How can that be easier than
turning off a stopcock?? Go on, tell me the trick, freezing kits don't
count!

Asuming you are just working on one rad; Close filling loop, turn off TRV's
& lockshields to all other rads.

Use wet vac to suck water out of rad (& some pipework) you are working on.

Use Fernox cartridge or Wickes pump to add inhibitor to said rad. Re open
all TRV's & lockshields to previous settings.

Open filling loop so gauge reads as it should, bleed said rad (using
microfibre cloth to catch any drips).

Repeat on other rads. Since all other rads were isolated there won't be
much to bleed anyway. System fills under mains pressure so no airlock
problems.

Owzat?


--
Dave - The Medway Handyman
www.medwayhandyman.co.uk

"dennis@home" wrote in message
...


"Arfa Daily" wrote in message
...

Turn the boiler off.
Then turn the water mains off.
Do your plumbing.
Turn the mains on.
Flush the pipes by operating the taps.
Turn the boiler back on.

If you forget to turn the boiler off it may turn on and you get steam
shooting out of your cut pipe work if you are unlucky or worse if you are
very unlucky.

Thanks all. Ok. Before going on to my other question on these combis, a part
1(a) to this question ...

Talking this through with said daughter tonight, it turns out that she wants
to replace the shower as well. This is a wall recessed 'conventional' mixer
shower with temperature and flow valves, and is over the bath, so presumably
fed from the same pair of pipes as feed the bath taps. I'm going to assume
that this has been in there since before the boiler was changed. Now, she
says that the pressure is not very good, so I'm wondering now as to what
sort of pressure would you expect from one of these boilers, because I'm
guessing that the pressure must be restricted from that of the rising main,
to allow the bloody thing time to heat the water as it passes through ??

As someone else had suggested, I was considering fitting a pair of service
valves to allow the rest of the system to be repowered, but I'm now thinking
that if the pressure really is low, then I'm not going to be doing myself or
her, any favours by dropping it still more with valves in the lines.

That aside, are any types of shower valve more suitable than others, for use
with combi boiler hot water systems ? Any specific recommendations ? She is
not going to be wanting to spend too much, and we are probably going to be
talking B&Q here (yes, I know, but she's only young ...)

TIA (again !)

Arfa

Arfa Daily wrote:

Thanks all. Ok. Before going on to my other question on these combis, a part
1(a) to this question ...

Talking this through with said daughter tonight, it turns out that she wants
to replace the shower as well. This is a wall recessed 'conventional' mixer
shower with temperature and flow valves, and is over the bath, so presumably
fed from the same pair of pipes as feed the bath taps. I'm going to assume

Well if it was plumbed properly, then the hot supply would have come
from the cylinder in the usual way and could well have shared a pipe
with the hot tap. The cold however ought ot have had a dedicated feed
from the cold tank in the loft (which would have been connected a little
lower down the tank so that the hot water would stop first should the
main tank drain completely). You will need to find if this is the case,
and how it has been replumbed if it was.

that this has been in there since before the boiler was changed. Now, she
says that the pressure is not very good, so I'm wondering now as to what
sort of pressure would you expect from one of these boilers, because I'm
guessing that the pressure must be restricted from that of the rising main,
to allow the bloody thing time to heat the water as it passes through ??

You need to distinguish between pressure and flow rate. Combi boilers
will usually deliver very good hot water pressure (assuming the cold
main does), and this usually results in a good forceful shower. The flow
rates they can deliver (especially the lower power ones often fitted)
can be less impressive when compared to a stored water system here[1].
For most showers this is not a problem unless the one she has required
vast flow rates as well - e.g. like the ones with body jets or big
diameter drencher heads.

[1] if the usual pedants are reading, yes we know this is not always the
case and you can do better etc, but we are talking generalisations here.

As someone else had suggested, I was considering fitting a pair of service
valves to allow the rest of the system to be repowered, but I'm now thinking
that if the pressure really is low, then I'm not going to be doing myself or
her, any favours by dropping it still more with valves in the lines.

At mains pressure this is going to have little impact. If in doubt you
could always use the so called "full bore" service valves - these do not
introduce any restriction.

That aside, are any types of shower valve more suitable than others, for use
with combi boiler hot water systems ? Any specific recommendations ? She is

A thermostatic one is best since the input temperatures can fluctuate
based on the actual demand for water in the house. e.g. a washing
machine deciding to fill while you are in the shower will not only drop
the pressure at the shower - it may also reduce the output temperature
of the combi by increasing the flow rate of the water through it. (note
most combis do not regulate to the flow themselves to control the output
temperature - they will typically regulate the gas rate to prevent a
user preset temperature limit being exceeded - but not the other way round.

not going to be wanting to spend too much, and we are probably going to be
talking B&Q here (yes, I know, but she's only young ...)

Something like one of the Bristain bar mixer type showers can be had for
under £100 in many places. Nothing special, but they will do the job and
are almost disposable at the price.

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

"Arfa Daily" wrote in message
news

"dennis@home" wrote in message
...


"Arfa Daily" wrote in message
...

Turn the boiler off.
Then turn the water mains off.
Do your plumbing.
Turn the mains on.
Flush the pipes by operating the taps.
Turn the boiler back on.

If you forget to turn the boiler off it may turn on and you get steam
shooting out of your cut pipe work if you are unlucky or worse if you are
very unlucky.

Thanks all. Ok. Before going on to my other question on these combis, a
part 1(a) to this question ...

Talking this through with said daughter tonight, it turns out that she
wants to replace the shower as well. This is a wall recessed
'conventional' mixer shower with temperature and flow valves, and is over
the bath, so presumably fed from the same pair of pipes as feed the bath
taps.


Not if it has been installed correctly.
It should have its own pipe work back to the cylinder and the cold tank.
It stops the temp changing when someone turns on the tap.
It works well if done right.

I'm going to assume that this has been in there since before the boiler
was changed. Now, she says that the pressure is not very good, so I'm
wondering now as to what sort of pressure would you expect from one of
these boilers, because I'm guessing that the pressure must be restricted
from that of the rising main, to allow the bloody thing time to heat the
water as it passes through ??

The pressure is mains, there may be a flow reducer in the boiler.
I fitted a pressure reducer (3.5 bar) in my dads to stop water splash in the
basin but it doesn't affect the shower much.


As someone else had suggested, I was considering fitting a pair of service
valves to allow the rest of the system to be repowered, but I'm now
thinking that if the pressure really is low, then I'm not going to be
doing myself or her, any favours by dropping it still more with valves in
the lines.

That aside, are any types of shower valve more suitable than others, for
use with combi boiler hot water systems ? Any specific recommendations ?
She is not going to be wanting to spend too much, and we are probably
going to be talking B&Q here (yes, I know, but she's only young ...)

Always fit a thermostatic one, they are cheap these days.
I like the mira ones but that's low end and only have a life of about 25
years.

On 4 Aug, 00:13, "The Medway Handyman"
wrote:

Asuming you are just working on one rad; *

Well that IS easy!