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Default Getting hot water from shower to actually be hot

Grrr. This is why I prefer proper stored hot water systems...

My shower has a mira Discovery thermostatic mixer, one of
these: http://goo.gl/0n7g

Try as I might I can't actually get the hot water to be hot.
With the temperature control turned all the way to "hot" it
just runs tepid, I end up shivering when trying to have a
shower. Following the instructions I've turned the internal
temperature control adjuster within the green temperture hub,
I've ended up turning it so far the worm scren is starting to
poke out of the hub, yet it *STILL* runs cold.

Basin mixer tap runs nice and hot, kitchen mixer tap runs
nice and hot.

Any advice?

At the place I used to live I had 25 gallons of hot water
sat waiting for me instantly onstandby.

JGH
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Default Getting hot water from shower to actually be hot

My shower has a mira Discovery thermostatic mixer, one of
these:http://goo.gl/0n7g


Sorry, no, actually one of these: http://goo.gl/rRg4

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Default Getting hot water from shower to actually be hot

jgharston wrote:
My shower has a mira Discovery thermostatic mixer, one of
these: http://goo.gl/rRg4


PS: Boiler is a oil-fired Warmflow Combi 90, serviced in June.

JGH
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Default Getting hot water from shower to actually be hot

On 26/10/2010 19:38, jgharston wrote:
Grrr. This is why I prefer proper stored hot water systems...

My shower has a mira Discovery thermostatic mixer, one of
these: http://goo.gl/0n7g

Try as I might I can't actually get the hot water to be hot.
With the temperature control turned all the way to "hot" it
just runs tepid, I end up shivering when trying to have a
shower. Following the instructions I've turned the internal
temperature control adjuster within the green temperture hub,
I've ended up turning it so far the worm scren is starting to
poke out of the hub, yet it *STILL* runs cold.

Basin mixer tap runs nice and hot, kitchen mixer tap runs
nice and hot.

Any advice?

At the place I used to live I had 25 gallons of hot water
sat waiting for me instantly onstandby.

JGH


If the water is hot at the sink then it's not the boiler or the system.
It must be the shower mixer. I've had one of those showers and it was fine.
Has it ever worked?
Are the hot and cold supply fitted correctly?
Is there a blockage in the hot supply?
If you stop cold water reaching the shower does hot water come out?
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Default Getting hot water from shower to actually be hot

nicknoxx wrote:
If the water is hot at the sink then it's not the boiler or the system.
It must be the shower mixer. I've had one of those showers and it was fine.
Has it ever worked?


Not since I moved in in May. It's only now getting
annoying as the weather gets colder.

Are the hot and cold supply fitted correctly?


Dunno, can only presume that the person who built/plumbed
the house last year fitted them correctly.

Is there a blockage in the hot supply?
If you stop cold water reaching the shower does hot water come out?


Hmm. That would be an interesting experiment, though how
I would do it without ripping out the wall on the other side
of the shower or breaking up the concrete floor I'm not
sure.

JGH


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Default Getting hot water from shower to actually be hot

On 26/10/2010 20:13, jgharston wrote:
nicknoxx wrote:
If the water is hot at the sink then it's not the boiler or the system.
It must be the shower mixer. I've had one of those showers and it was fine.
Has it ever worked?


Not since I moved in in May. It's only now getting
annoying as the weather gets colder.

Are the hot and cold supply fitted correctly?


Dunno, can only presume that the person who built/plumbed
the house last year fitted them correctly.

Is there a blockage in the hot supply?
If you stop cold water reaching the shower does hot water come out?


Hmm. That would be an interesting experiment, though how
I would do it without ripping out the wall on the other side
of the shower or breaking up the concrete floor I'm not
sure.

JGH


Hmmm, looks like you'll have to have the shower mixer off the wall then
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Default Getting hot water from shower to actually be hot

On 26/10/2010 19:38, jgharston wrote:

Any advice?


Turn it half way and stick your hand under it. Then turn it up
gradually and feel what happens. Then report back!

Andy
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Andy Champ wrote:
Turn it half way and stick your hand under it. *Then turn it up
gradually and feel what happens. *Then report back!


At halfway, runs at 37degrees.
After 30 seconds turned up to full hot.
Continued running at 37 degress.

JGH
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Default Getting hot water from shower to actually be hot

jgharston wrote:
At halfway, runs at 37degrees.
After 30 seconds turned up to full hot.
Continued running at 37 degress.


Hot water in the basin runs at 47 degrees.

JGH
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"Andy Champ" wrote in message
. uk...
On 26/10/2010 19:38, jgharston wrote:

Any advice?


Turn it half way and stick your hand under it. Then turn it up gradually
and feel what happens. Then report back!

Andy


Can you check the temp at a tap whilst the shower is running? You may be
'blaming' the shower when it is the boiler that is lacking capacity.

I have a Mira 415 and I needed to fit a flow reducer in the winter to allow
the boiler to cope - it was delivering 12 litres a minute and the boiler
struggled. It is now 9 litres a minute and it is fine




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"John" wrote in message
...
"Andy Champ" wrote in message
. uk...
On 26/10/2010 19:38, jgharston wrote:

Any advice?


Turn it half way and stick your hand under it. Then turn it up gradually
and feel what happens. Then report back!

Andy


Can you check the temp at a tap whilst the shower is running? You may be
'blaming' the shower when it is the boiler that is lacking capacity.

I have a Mira 415 and I needed to fit a flow reducer in the winter to
allow the boiler to cope - it was delivering 12 litres a minute and the
boiler struggled. It is now 9 litres a minute and it is fine



I realise now that your has a "flow" control (mine doesn't). Is the problem
there at lower flow rates?


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Default Getting hot water from shower to actually be hot

On 27/10/2010 7:38 a.m., jgharston wrote:
Grrr. This is why I prefer proper stored hot water systems...

My shower has a mira Discovery thermostatic mixer, one of
these: http://goo.gl/0n7g

Try as I might I can't actually get the hot water to be hot.
With the temperature control turned all the way to "hot" it
just runs tepid, I end up shivering when trying to have a
shower. Following the instructions I've turned the internal
temperature control adjuster within the green temperture hub,
I've ended up turning it so far the worm scren is starting to
poke out of the hub, yet it *STILL* runs cold.

Basin mixer tap runs nice and hot, kitchen mixer tap runs
nice and hot.

Any advice?

At the place I used to live I had 25 gallons of hot water
sat waiting for me instantly onstandby.

JGH


Possibly the pressure in the hot system is too low. We had a new cylinder
installed recently and at first the pressure was too low - hot water in the
basins, but the shower mixer dropped the flow right down. The plumber came back
and cranked up the pressure reducing valve (whatever it's called), and now it's
fine.
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Default Getting hot water from shower to actually be hot

Gib Bogle wrote:
Possibly the pressure in the hot system is too low. *We had a new cylinder
installed recently and at first the pressure was too low - hot water in the


There's no cylinder, that's what's annoying. I'm used to a
cylinder with 25 gallons of hot water sitting there waiting
for me to use it at any time, not waiting for a boiler to
suddenly wake up and desperately try to heat the water
as it rushes past it.

basins, but the shower mixer dropped the flow right down. *The plumber came back
and cranked up the pressure reducing valve (whatever it's called), and now it's
fine.


That might do it. I'll have a chat with the landlord (or see
if I can find it myself).

JGH
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"Gib Bogle" wrote in message
...
On 27/10/2010 7:38 a.m., jgharston wrote:
Grrr. This is why I prefer proper stored hot water systems...

My shower has a mira Discovery thermostatic mixer, one of
these: http://goo.gl/0n7g

Try as I might I can't actually get the hot water to be hot.
With the temperature control turned all the way to "hot" it
just runs tepid, I end up shivering when trying to have a
shower. Following the instructions I've turned the internal
temperature control adjuster within the green temperture hub,
I've ended up turning it so far the worm scren is starting to
poke out of the hub, yet it *STILL* runs cold.

Basin mixer tap runs nice and hot, kitchen mixer tap runs
nice and hot.

Any advice?

At the place I used to live I had 25 gallons of hot water
sat waiting for me instantly onstandby.

JGH


Possibly the pressure in the hot system is too low. We had a new cylinder
installed recently and at first the pressure was too low - hot water in
the basins, but the shower mixer dropped the flow right down. The plumber
came back and cranked up the pressure reducing valve (whatever it's
called), and now it's fine.


Trace the pipes - do you perhaps have mains cold on one side and gravity hot
on the other?


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On Tue, 26 Oct 2010 22:12:32 +0100, John wrote:

I have a Mira 415 and I needed to fit a flow reducer in the winter

to
allow the boiler to cope - it was delivering 12 litres a minute

and the
boiler struggled. It is now 9 litres a minute and it is fine


I realise now that your has a "flow" control (mine doesn't). Is the
problem there at lower flow rates?


Good test and I'd go with lack of capacity in the boiler especially
as it's only since the supply started getting colder that the problem
has appeared. Another thing is the OP not finding a "safety
interlock" that prevents the shower going above 38C or 43C (ie cold
to tepid) unless defeated. Though it doesn't look like this one has
such a "feature".

--
Cheers
Dave.





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Gib Bogle wrote:
On 27/10/2010 7:38 a.m., jgharston wrote:
Grrr. This is why I prefer proper stored hot water systems...

My shower has a mira Discovery thermostatic mixer, one of
these: http://goo.gl/0n7g

Try as I might I can't actually get the hot water to be hot.
With the temperature control turned all the way to "hot" it
just runs tepid, I end up shivering when trying to have a
shower. Following the instructions I've turned the internal
temperature control adjuster within the green temperture hub,
I've ended up turning it so far the worm scren is starting to
poke out of the hub, yet it *STILL* runs cold.

Basin mixer tap runs nice and hot, kitchen mixer tap runs
nice and hot.

Any advice?

At the place I used to live I had 25 gallons of hot water
sat waiting for me instantly onstandby.

JGH


Possibly the pressure in the hot system is too low.


Its combi dear.

There is no 'hot water' system as such.
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In article
,
jgharston wrote:
Grrr. This is why I prefer proper stored hot water systems...


My shower has a mira Discovery thermostatic mixer, one of
these: http://goo.gl/0n7g


Try as I might I can't actually get the hot water to be hot.
With the temperature control turned all the way to "hot" it
just runs tepid, I end up shivering when trying to have a
shower. Following the instructions I've turned the internal
temperature control adjuster within the green temperture hub,
I've ended up turning it so far the worm scren is starting to
poke out of the hub, yet it *STILL* runs cold.


It seems to be designed for either low or high pressure systems. Assuming
yours is high pressure being a combi perhaps the cold flow is too great
for the mixer to compensate for? You could prove that quite easily by
cutting it down on the main stop cock.

--
*Why do we say something is out of whack? What is a whack?

Dave Plowman London SW
To e-mail, change noise into sound.
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John wrote:
Trace the pipes


Don't want to dig up the concrete floor or bash holes in the
stud walls.

do you perhaps have mains cold on one side and gravity hot
on the other?


No, it's a combi with no cylinder - ie mains cold, mains hot.

JGH
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Dave Plowman (News) wrote:
It seems to be designed for either low or high pressure systems. Assuming
yours is high pressure being a combi perhaps the cold flow is too great
for the mixer to compensate for? You could prove that quite easily by
cutting it down on the main stop cock.


Yes, that heats it up. However, it also cuts the flow (!)
just as I've always experienced with non-stored systems.
You throw away water flow in exchange for heat, and the
cross-over point is always too crap for either.

It just manages to get up to 44 degrees with water running
out at a trickle. Proper decent pressure gives a temperature
of 35 degrees, brrrr!!!!

Just after the stop-tap there's an inline connector with a
nut on the side that I've never seen before, looks a bit like
this: http://plumbworld.co.uk/compression-...check-222-3991

This is a new-build house in Aberdeenshire, it's about 18
months old.

JGH
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Default Getting hot water from shower to actually be hot

On 27/10/2010 12:04 p.m., The Natural Philosopher wrote:
Gib Bogle wrote:
On 27/10/2010 7:38 a.m., jgharston wrote:
Grrr. This is why I prefer proper stored hot water systems...

My shower has a mira Discovery thermostatic mixer, one of
these: http://goo.gl/0n7g

Try as I might I can't actually get the hot water to be hot.
With the temperature control turned all the way to "hot" it
just runs tepid, I end up shivering when trying to have a
shower. Following the instructions I've turned the internal
temperature control adjuster within the green temperture hub,
I've ended up turning it so far the worm scren is starting to
poke out of the hub, yet it *STILL* runs cold.

Basin mixer tap runs nice and hot, kitchen mixer tap runs
nice and hot.

Any advice?

At the place I used to live I had 25 gallons of hot water
sat waiting for me instantly onstandby.

JGH


Possibly the pressure in the hot system is too low.


Its combi dear.

There is no 'hot water' system as such.


I don't follow you, sweetheart. We had low pressure at all the hot taps, good
pressure on the cold. After adjustment of the diaphragm thingie on the hw
cylinder inlet, we now have good pressure on all hot taps. OK darling?


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Gib Bogle wrote:
I don't follow you, sweetheart. *We had low pressure at all the hot taps, good
pressure on the cold. *After adjustment of the diaphragm thingie on the hw
cylinder inlet, we now have good pressure on all hot taps. *OK darling?

^^^^^^^^^^^^^^^^

Exactly sweetie, I *don't* have a hot water cylinder, hot
water is supplied on demand by being heated as the cold
water flows through the boiler. If it flows flowly enough to
be heated to a useful temparture, it's flowing too slowly
for a decent shower. If it's flowing fast enough for a decent
shower, it's flowing through the boiler too fast for it to be
heated up, escpecially now that the cold supply arrives
at 8 degrees since the snow stared. This is why I hate
non-stored hot water systems.

JGH
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On 27/10/2010 1:01 p.m., jgharston wrote:
Gib Bogle wrote:
I don't follow you, sweetheart. We had low pressure at all the hot taps, good
pressure on the cold. After adjustment of the diaphragm thingie on the hw
cylinder inlet, we now have good pressure on all hot taps. OK darling?

^^^^^^^^^^^^^^^^

Exactly sweetie, I *don't* have a hot water cylinder, hot
water is supplied on demand by being heated as the cold
water flows through the boiler. If it flows flowly enough to
be heated to a useful temparture, it's flowing too slowly
for a decent shower. If it's flowing fast enough for a decent
shower, it's flowing through the boiler too fast for it to be
heated up, escpecially now that the cold supply arrives
at 8 degrees since the snow stared. This is why I hate
non-stored hot water systems.

JGH


That's the first time I've heard of a 'combi' system. Sometimes posting to
uk.d-i-y from NZ does make a difference.
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On 27 Oct, 00:46, Gib Bogle wrote:
On 27/10/2010 12:04 p.m., The Natural Philosopher wrote:





Gib Bogle wrote:
On 27/10/2010 7:38 a.m., jgharston wrote:
Grrr. This is why I prefer proper stored hot water systems...


My shower has a mira Discovery thermostatic mixer, one of
these:http://goo.gl/0n7g


Try as I might I can't actually get the hot water to be hot.
With the temperature control turned all the way to "hot" it
just runs tepid, I end up shivering when trying to have a
shower. Following the instructions I've turned the internal
temperature control adjuster within the green temperture hub,
I've ended up turning it so far the worm scren is starting to
poke out of the hub, yet it *STILL* runs cold.


Basin mixer tap runs nice and hot, kitchen mixer tap runs
nice and hot.


Any advice?


At the place I used to live I had 25 gallons of hot water
sat waiting for me instantly onstandby.


JGH


Possibly the pressure in the hot system is too low.


Its combi dear.


There is no 'hot water' system as such.


I don't follow you, sweetheart. *We had low pressure at all the hot taps, good
pressure on the cold. *After adjustment of the diaphragm thingie on the hw
cylinder inlet, we now have good pressure on all hot taps. *OK darling?- Hide quoted text -

- Show quoted text -


If it's a combi, there is no cylinder.
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harry wrote:
If it's a combi, there is no cylinder.


Not neccessarily. At my old place I had a combi boiler
with hot water cylinder. I specifically specified keeping
the cylinder when the old boiler was replaced specifically
to avoid the crapness we've been discussing.

JGH
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Gib Bogle wrote:
On 27/10/2010 12:04 p.m., The Natural Philosopher wrote:
Gib Bogle wrote:
On 27/10/2010 7:38 a.m., jgharston wrote:
Grrr. This is why I prefer proper stored hot water systems...

My shower has a mira Discovery thermostatic mixer, one of
these: http://goo.gl/0n7g

Try as I might I can't actually get the hot water to be hot.
With the temperature control turned all the way to "hot" it
just runs tepid, I end up shivering when trying to have a
shower. Following the instructions I've turned the internal
temperature control adjuster within the green temperture hub,
I've ended up turning it so far the worm scren is starting to
poke out of the hub, yet it *STILL* runs cold.

Basin mixer tap runs nice and hot, kitchen mixer tap runs
nice and hot.

Any advice?

At the place I used to live I had 25 gallons of hot water
sat waiting for me instantly onstandby.

JGH

Possibly the pressure in the hot system is too low.


Its combi dear.

There is no 'hot water' system as such.


I don't follow you, sweetheart. We had low pressure at all the hot
taps, good pressure on the cold. After adjustment of the diaphragm
thingie on the hw cylinder inlet, we now have good pressure on all hot
taps. OK darling?

combis dont have hot water tanks


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Gib Bogle wrote:
On 27/10/2010 1:01 p.m., jgharston wrote:
Gib Bogle wrote:
I don't follow you, sweetheart. We had low pressure at all the hot
taps, good
pressure on the cold. After adjustment of the diaphragm thingie on
the hw
cylinder inlet, we now have good pressure on all hot taps. OK darling?

^^^^^^^^^^^^^^^^

Exactly sweetie, I *don't* have a hot water cylinder, hot
water is supplied on demand by being heated as the cold
water flows through the boiler. If it flows flowly enough to
be heated to a useful temparture, it's flowing too slowly
for a decent shower. If it's flowing fast enough for a decent
shower, it's flowing through the boiler too fast for it to be
heated up, escpecially now that the cold supply arrives
at 8 degrees since the snow stared. This is why I hate
non-stored hot water systems.

JGH


That's the first time I've heard of a 'combi' system.


with luck, it will be the last as well.

spawn of the devil.

A combi is to what we used to call a 'geyser' as a wimnd turbione is to
a traditional windmill.

I.e. a really crap idea dressed up in modern clothes and sold on the
basis that it actually does something useful after all.

The only 'combi' I have used that really worked for hot water, was the
one my sister had in germany. It lived in the basement and was the size
of a family car. That actually could produce a hot shower.



Sometimes posting
to uk.d-i-y from NZ does make a difference.

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jgharston wrote:
harry wrote:
If it's a combi, there is no cylinder.


Not neccessarily. At my old place I had a combi boiler
with hot water cylinder. I specifically specified keeping
the cylinder when the old boiler was replaced specifically
to avoid the crapness we've been discussing.

Then why did you bother with a combi boiler?


JGH

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"jgharston" wrote in message
...
Dave Plowman (News) wrote:
It seems to be designed for either low or high pressure systems. Assuming
yours is high pressure being a combi perhaps the cold flow is too great
for the mixer to compensate for? You could prove that quite easily by
cutting it down on the main stop cock.


Yes, that heats it up. However, it also cuts the flow (!)
just as I've always experienced with non-stored systems.
You throw away water flow in exchange for heat, and the
cross-over point is always too crap for either.

It just manages to get up to 44 degrees with water running
out at a trickle. Proper decent pressure gives a temperature
of 35 degrees, brrrr!!!!

Just after the stop-tap there's an inline connector with a
nut on the side that I've never seen before, looks a bit like
this: http://plumbworld.co.uk/compression-...check-222-3991

This is a new-build house in Aberdeenshire, it's about 18
months old.

JGH




My combi based installation has a couple of valves in the loft that can be
crudely used to adjust flow. The hot one suffered from the washer swelling
and restricting the flow.


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In article ,
The Natural Philosopher wrote:
I don't follow you, sweetheart. We had low pressure at all the hot
taps, good pressure on the cold. After adjustment of the diaphragm
thingie on the hw cylinder inlet, we now have good pressure on all hot
taps. OK darling?


combis dont have hot water tanks


I'm amazed dribble hasn't been here yet. ;-)

Don't some store a small amount of hot water to get over the initial wait
from those without?

No reason why you couldn't heat a cylinder from a combi. And keep the
'instant' feature for the kitchen tap.

--
*If your feet smell and your nose runs, you're built upside down.

Dave Plowman London SW
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"Dave. ;-)

Don't some store a small amount of hot water to get over the initial wait
from those without?




My Worcester Heatslave floor standing one had this feature - the problem was
though that the stored water was hotter than what the boiler could produce
for a shower which meant that the shower started off really hot using the
stored water and then got a bit cooler. However - never a big problem - more
one of it being too hot to start with.




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On 26 Oct, 19:38, jgharston wrote:
Grrr. This is why I prefer proper stored hot water systems...

My shower has a mira Discovery thermostatic mixer, one of
these:http://goo.gl/0n7g

Try as I might I can't actually get the hot water to be hot.
With the temperature control turned all the way to "hot" it


It's a TMV and comes factory set to a (low) maximum temperature (43
deg or so typically) which is low enough not to cause scalding to
elderly or disabled people if installed in a care home or such. The
idea is the makers don't get sued when a numpty plumber causes
scalding to someone's granny. You can alter the maximum temperature,
usually involves taking knobs off and such. See manufacturer's
installation instructions.
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Default Getting hot water from shower to actually be hot

On 27 Oct, 10:09, Onetap wrote:
On 26 Oct, 19:38, jgharston wrote:

Grrr. This is why I prefer proper stored hot water systems...


My shower has a mira Discovery thermostatic mixer, one of
these:http://goo.gl/0n7g


Try as I might I can't actually get the hot water to be hot.
With the temperature control turned all the way to "hot" it


It's a TMV and comes factory set to a (low) maximum temperature (43
deg or so typically) which is low enough not to cause scalding to
elderly or disabled people if installed in a care home or such. The
idea is the makers don't get sued when a numpty plumber causes
scalding to someone's granny. You can alter the maximum temperature,
usually involves taking knobs off and such. See manufacturer's
installation instructions.


No, ignore that. You've done it.

probably unequal pressures or a defective cartridge.

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Dave Plowman (News) wrote:
In article ,
The Natural Philosopher wrote:
I don't follow you, sweetheart. We had low pressure at all the hot
taps, good pressure on the cold. After adjustment of the diaphragm
thingie on the hw cylinder inlet, we now have good pressure on all hot
taps. OK darling?


combis dont have hot water tanks


I'm amazed dribble hasn't been here yet. ;-)

Don't some store a small amount of hot water to get over the initial wait
from those without?

No reason why you couldn't heat a cylinder from a combi. And keep the
'instant' feature for the kitchen tap.

No reason why you would install a combi with hot water storage.

The reason combis exist, is that the cost of a combi is less than a
conventional lower powered boiler plus hot water tank, plus shower pump
plus header tank.

Or less than a conenvtional boiler plus mains pressure tank.

Once you start adding heat banks or a cylinder to a combi, to make it
work better, the cost then exceeds a conventional boiler and mains
pressure tank.




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"Dave Plowman (News)" wrote in message
...

No reason why you couldn't heat a cylinder from a combi. And keep the
'instant' feature for the kitchen tap.


Not a lot of point doing that, you just need to insulate the tank and pipes
and use a non combi bolier.
A hot water cylinder is just a dedicated heat store and has the same
advantages (unless its a bungaloo).

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On Oct 26, 9:31*pm, jgharston wrote:
jgharston wrote:
At halfway, runs at 37degrees.
After 30 seconds turned up to full hot.
Continued running at 37 degress.


Hot water in the basin runs at 47 degrees.



That's not very hot either. It there a thermostat on the boiler that
controls the outlet temperature? What is the boiler's rated power?
Robert



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"jgharston" wrote in message
...
Gib Bogle wrote:
Possibly the pressure in the hot system is too low. We had a new cylinder
installed recently and at first the pressure was too low - hot water in
the


There's no cylinder, that's what's annoying. I'm used to a
cylinder with 25 gallons of hot water sitting there waiting
for me to use it at any time, not waiting for a boiler to
suddenly wake up and desperately try to heat the water
as it rushes past it.

basins, but the shower mixer dropped the flow right down. The plumber came
back
and cranked up the pressure reducing valve (whatever it's called), and now
it's
fine.


That might do it. I'll have a chat with the landlord (or see
if I can find it myself).

Ah! Are you in Scotland by any chance? It's possible that there's been a
thermostatic mixing valve installed somewhere (that pre-dates the present
shower control valve) that's restricting maximum HW temp.

Tim

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"jgharston" wrote in message
...
Gib Bogle wrote:
Possibly the pressure in the hot system is too low. We had a new cylinder
installed recently and at first the pressure was too low - hot water in
the


There's no cylinder, that's what's annoying. I'm used to a
cylinder with 25 gallons of hot water sitting there waiting
for me to use it at any time, not waiting for a boiler to
suddenly wake up and desperately try to heat the water
as it rushes past it.

basins, but the shower mixer dropped the flow right down. The plumber came
back
and cranked up the pressure reducing valve (whatever it's called), and now
it's
fine.


That might do it. I'll have a chat with the landlord (or see
if I can find it myself).

#########################################

Are you in Scotland by any chance? It's possible that there's been a
thermostatic mixing valve installed somewhere (that pre-dates the present
shower control valve) that's restricting maximum HW temp.

Tim

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On 27 Oct, 13:30, "dennis@home" wrote:
"Dave Plowman (News)" wrote in ...

No reason why you couldn't heat a cylinder from a combi. And keep the
'instant' feature for the kitchen tap.



Interesting - I've yet to find a combi supplied kitchen tap that was
'instant'.

I have a traditional system, and get hot water through in reasonable
time and with good flow - I think every house I've been into in which
the hot water is combi supplied, the wait has been extensive and the
flow weak.
Rob

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robgraham wrote:
On 27 Oct, 13:30, "dennis@home" wrote:
"Dave Plowman (News)" wrote in ...

No reason why you couldn't heat a cylinder from a combi. And keep the
'instant' feature for the kitchen tap.


Interesting - I've yet to find a combi supplied kitchen tap that was
'instant'.

I have a traditional system, and get hot water through in reasonable
time and with good flow - I think every house I've been into in which
the hot water is combi supplied, the wait has been extensive and the
flow weak.

Correct.

You need something like a 50KW combi to heat hot water really fast.

Which then needs to run at much less to do CH. Which is why the better
designs modulate down. But even so, efficiency is poor.

And the requrements are quite different as well. Optimal outflow for
modern radiators in not freezing temps might be as low as 35-40C.

Optimum hot water as far as I am concerned is 60C or so.

Rob

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On 26/10/10 22:12, John wrote:

I realise now that your has a "flow" control (mine doesn't). Is the problem
there at lower flow rates?



Google for E-on showersave. They were doing a promo with Anglian Water where
they were sending these out free. Fits in line with the shower hose or shower
head and limits the flow rate to around 9l/min.

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