On Fri, 13 Feb 2004 13:58:29 -0000, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Fri, 13 Feb 2004 09:14:00 -0000, "IMM" wrote:


Put it another way.

I know from personal experience that ion exchange softeners work.

No one said they didn't work.

"not worth their salt" was the comment from a not-disinterested "pro"



I can test the water and I know that less detergent is required than
without. I also know the chemical processes by which they work.

I know from personal experience that phosphate dosing works. I have
seen the results of that and again there is a well understood
mechanism.

I have seen from the experience of neighbours using exactly the same
water supply that I have that electronic and magnetic conditioners
don't work.

Mine works. And these pros tended to agree they worked too, who have
greater exposure than you.

I suspect their main exposure is their backsides in the plumber's
merchants.





I take that into account when they sing the praises of it,
that this might not be an unbiased view.

And the customers said it worked and kept it.

or they didn't notice that there was no effect but didn't care.

If you read it he was called to a scaled up Responses, descaled it and
fitted a Scalewatcher. The customer would know the difference.

....until the next heat exchanger is required, anyway.


..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
On Fri, 13 Feb 2004 13:58:29 -0000, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Fri, 13 Feb 2004 09:14:00 -0000, "IMM" wrote:


Put it another way.

I know from personal experience that ion exchange softeners work.

No one said they didn't work.

"not worth their salt" was the comment from a not-disinterested "pro"

That was clearly price performance, space taken up, etc. That was clear.

I can test the water and I know that less detergent is required than
without. I also know the chemical processes by which they work.

I know from personal experience that phosphate dosing works. I have
seen the results of that and again there is a well understood
mechanism.

I have seen from the experience of neighbours using exactly the same
water supply that I have that electronic and magnetic conditioners
don't work.

Mine works. And these pros tended to agree they worked too, who have
greater exposure than you.

I suspect their main exposure is their backsides in the plumber's
merchants.

LOL, such wonder Little Middle England humour.

I take that into account when they sing the praises of it,
that this might not be an unbiased view.

And the customers said it worked and kept it.

or they didn't notice that there was no effect but didn't care.

If you read it he was called to a scaled up Responses, descaled it and
fitted a Scalewatcher. The customer would know the difference.

...until the next heat exchanger is required, anyway.

Why, do you know about Responses and the scale?

Ion exchange works very well.

To add to this, there are considerable differences in ion exchange water
softeners. The two main differences are the method of regeneration and the
flow rates of the system.

Maximum flow rates and pressure drops vary from valve design to valve
design. All are suitable for topping up a loft tank. However, a house on a
mains pressure system, such as a combi boiler, unvented cylinder, or heat
bank must choose wisely to ensure that the pressure drop for the expected
flow rate is low, and that the system is capable of performing the ion
exchange at such a high flow rate without letting hard ions through.

When installing a high flow rate system, it is best to throw away the
washing machine hoses provided and use full bore valves and fixed pipework,
leaving only the valve and cylinders to reduce flow rate capacity.

As for the method of regeneration, there are many strategies. The cheapest
is to use a timer to regenerate in the middle of the night every 'x' days.
The disadvantages of this is that the system may regenerate too frequently
when usage is low and run out with usage is high.

A metered system regenerates after a certain amount of water is used. This
prevents wastage, but means that regeneration may occur at an inconvenient
point and allow hard water through.

A combination system will regenerate during the night after the system is
mostly depleted. Some systems of this type are very sophisticated and will
predict your usage depending on past usage to determine the best time to
regenerate. Some can do a non-full regeneration if they consider it optimum.

The best systems, however, simply have two canisters. When the metering
indicates a change, the system swaps over and the depleted canister is
regenerated. This gives soft water 24 hours a day and minimum wastage of
water and salt. These systems typically cost much more, around the 1000
pounds mark, rather than 500 for a high flow rate sophisticated meter, or
300 for a cheapo timed version.

Christian.

Christian McArdle wrote:

Ion exchange works very well.


To add to this, there are considerable differences in ion exchange water
softeners. The two main differences are the method of regeneration and the
flow rates of the system.

Maximum flow rates and pressure drops vary from valve design to valve
design. All are suitable for topping up a loft tank. However, a house on a
mains pressure system, such as a combi boiler, unvented cylinder, or heat
bank must choose wisely to ensure that the pressure drop for the expected
flow rate is low, and that the system is capable of performing the ion
exchange at such a high flow rate without letting hard ions through.

When installing a high flow rate system, it is best to throw away the
washing machine hoses provided and use full bore valves and fixed pipework,
leaving only the valve and cylinders to reduce flow rate capacity.

As for the method of regeneration, there are many strategies. The cheapest
is to use a timer to regenerate in the middle of the night every 'x' days.
The disadvantages of this is that the system may regenerate too frequently
when usage is low and run out with usage is high.

A metered system regenerates after a certain amount of water is used. This
prevents wastage, but means that regeneration may occur at an inconvenient
point and allow hard water through.

A combination system will regenerate during the night after the system is
mostly depleted. Some systems of this type are very sophisticated and will
predict your usage depending on past usage to determine the best time to
regenerate. Some can do a non-full regeneration if they consider it optimum.

The best systems, however, simply have two canisters. When the metering
indicates a change, the system swaps over and the depleted canister is
regenerated. This gives soft water 24 hours a day and minimum wastage of
water and salt. These systems typically cost much more, around the 1000
pounds mark, rather than 500 for a high flow rate sophisticated meter, or
300 for a cheapo timed version.


And at £5 a month for salt, that's a lot of months before they pay for
themselves.



Christian.

On Fri, 13 Feb 2004 21:51:42 +0000, The Natural Philosopher
wrote:



And at £5 a month for salt, that's a lot of months before they pay for
themselves.


Don't forget the detergent and shampoo savings. That generally mopre
than covers the salt cost.


..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
news
On Fri, 13 Feb 2004 21:51:42 +0000, The Natural Philosopher
wrote:



And at £5 a month for salt, that's a lot of months before they pay for
themselves.

Don't forget the detergent and shampoo savings. That generally mopre
than covers the salt cost.

You are kidding.

The Natural Philosopher wrote in message ...

And at £5 a month for salt, that's a lot of months before they pay for
themselves.

Superficially that is correct. However, my experience is that the washing
machine and dishwasher last a lot longer, she doesn't make me descale the
taps etc every 6 weeks, the car is easier to wash( not rinse), so I think
it's worth it!

By the way, I don't believe the electronic controllers are worthwhile when
compared with a crude timer. The chance of buying electronics spares after a
few years can be very iffy and if you have a large enough loft tank, the
volume of water in the tank may maintain a lower hardness level even if
regeneration is a day delayed. Anyway, you soon notice if the soap doesn't
lather, and do something about it. Generally, refill it with salt!
Regards
Capitol

"IMM" wrote in message
...

"Andy Hall" wrote in message
news
On Fri, 13 Feb 2004 21:51:42 +0000, The Natural Philosopher
wrote:



And at £5 a month for salt, that's a lot of months before they pay for
themselves.

Don't forget the detergent and shampoo savings. That generally mopre
than covers the salt cost.

You are kidding.



You'll have so much soap you'll use more water to get rid of it.

On Fri, 13 Feb 2004 22:34:06 -0000, "IMM" wrote:


"Andy Hall" wrote in message
news
On Fri, 13 Feb 2004 21:51:42 +0000, The Natural Philosopher
wrote:



And at £5 a month for salt, that's a lot of months before they pay for
themselves.

Don't forget the detergent and shampoo savings. That generally mopre
than covers the salt cost.

You are kidding.

Nope. I posted calculations on this before based on real numbers.
I'm not doing it again. Look on Google Groups if you want to find
it.


..andy

To email, substitute .nospam with .gl

On Fri, 13 Feb 2004 22:41:33 -0000, "Martin"
wrote:

"IMM" wrote in message
...

"Andy Hall" wrote in message
news
On Fri, 13 Feb 2004 21:51:42 +0000, The Natural Philosopher
wrote:



And at £5 a month for salt, that's a lot of months before they pay for
themselves.

Don't forget the detergent and shampoo savings. That generally mopre
than covers the salt cost.

You are kidding.



You'll have so much soap you'll use more water to get rid of it.

After a short while, you realise that you can use much less and do so.

If you look at the recommended dosings of detergents, it ranges from
2:1 to 3:1 between hard and soft water.



..andy

To email, substitute .nospam with .gl

Andy Hall wrote:

On Fri, 13 Feb 2004 21:51:42 +0000, The Natural Philosopher
wrote:



And at £5 a month for salt, that's a lot of months before they pay for
themselves.



Don't forget the detergent and shampoo savings. That generally mopre
than covers the salt cost.



It's not relevant when comparing one ion exchange with another.

Which was I thgink the point under discussion - the complex ones don't
soften the water better, they just use less salt.



.andy

To email, substitute .nospam with .gl

IMM wrote:

"Andy Hall" wrote in message
news
On Fri, 13 Feb 2004 21:51:42 +0000, The Natural Philosopher
wrote:



And at £5 a month for salt, that's a lot of months before they pay for
themselves.


Don't forget the detergent and shampoo savings. That generally mopre
than covers the salt cost.


You are kidding.


No, he isn't. Maybe you don't use soap tho.

The Great Unwashed?

Capitol wrote:

The Natural Philosopher wrote in message ...


And at £5 a month for salt, that's a lot of months before they pay for
themselves.


Superficially that is correct. However, my experience is that the washing
machine and dishwasher last a lot longer, she doesn't make me descale the
taps etc every 6 weeks, the car is easier to wash( not rinse), so I think
it's worth it!



You have missed the point. I was comparing the cots of a 1000 quid
microprocessor equipped machine with a simple 300 quid 'recharge every
week timer' machine.

My point being that all the expensive one does is save on salt.

But you can buy about 140 months of salt with that 700 quid, so if - say
- the 1000 quid one saves half teh salt - at £60 a year on the cheapo,
thats £30 quid a year saved for the extra 700 quid. Now to borrow the
700 quid you are probably talking about - say - 6% APR? so it costs you
£42 a year to save £30?

Its a no brainer.


By the way, I don't believe the electronic controllers are worthwhile when
compared with a crude timer. The chance of buying electronics spares after a
few years can be very iffy and if you have a large enough loft tank, the
volume of water in the tank may maintain a lower hardness level even if
regeneration is a day delayed. Anyway, you soon notice if the soap doesn't
lather, and do something about it. Generally, refill it with salt!


Precisely. I have one that wasn't too expensive, and does regenerate
automatically depending on flow rate. I preprogrammed water hardness in.
That seems to be about right. I only notice hardness building up when it
runs out of salt.

However if I could have got the flow rate on a cheaper model I would
have gone for it. Maybe there is a cheap high reate one out there, but I
didn;t come across it.


BTW on electronic descalers, these only ever claimed to stop scaling by
adjusting the crystal types of the calcium solids. They don't soften the
water as far as soap goes at all. They merely stop (allegedly) hard
scale developing - the chalky stuff is supposed to stay in suspension
and run out with the waste.

If you want a better wash and less soap, you need ion exchange and thats it.


Regards
Capitol

On Sat, 14 Feb 2004 03:07:43 +0000, The Natural Philosopher
wrote:

Andy Hall wrote:

On Fri, 13 Feb 2004 21:51:42 +0000, The Natural Philosopher
wrote:



And at £5 a month for salt, that's a lot of months before they pay for
themselves.



Don't forget the detergent and shampoo savings. That generally mopre
than covers the salt cost.



It's not relevant when comparing one ion exchange with another.

Which was I thgink the point under discussion - the complex ones don't
soften the water better, they just use less salt.



OK.




..andy

To email, substitute .nospam with .gl

I have looked at this thread
http://tinyurl.com/3ef9x
and others on Google Groups to try and answer my questions, but found
nothing definitive.

I am renovating my house and plan to install a completely new gas-fired
central heating and hot water plumbing system. The renovation includes a
loft conversion, so I want to avoid a system that involves header tanks. I
am assuming that this means a sealed system for mains pressure hot water.

The heating system will be underfloor heating (typically 55 deg C), plus
supplementary heating (probably conventional radiators at 80 deg C flow) for
when the weather turns really cold.

I would like to install a water softener (not a water conditioner) that is
compatible with a sealed system and a few on this newgroup have recommended
an ion exchange type. Does anyone have a personal experience, successful or
otherwise, with a water softener and sealed system that might influence my
choice of softener and boiler. What makes of these do you have?

The main supply water pressure at my property is 2.8 bar (measured one
February lunchtime). My wife and I have three small children, one bath, two
showers and three toilets as well as a frequently-used washing machine and
dishwasher. With the old oil-fired vented system we used to have, our water
bills show a consumption of about 200 cu.m. per year.

A difficult question I know, but can any expert out there recommend a
"dream" boiler-type/storage tank/heat exchanger so that I could start to put
together a system specification that has a good chance of working? I would
rather err on the side of buying good quality equipment than a cheap
solution.

John Aston wrote:
I have looked at this thread
http://tinyurl.com/3ef9x
and others on Google Groups to try and answer my questions, but found
nothing definitive.

I am renovating my house and plan to install a completely new gas-fired
central heating and hot water plumbing system. The renovation includes a
loft conversion, so I want to avoid a system that involves header tanks. I
am assuming that this means a sealed system for mains pressure hot water.

The heating system will be underfloor heating (typically 55 deg C), plus
supplementary heating (probably conventional radiators at 80 deg C flow) for
when the weather turns really cold.

I would like to install a water softener (not a water conditioner) that is
compatible with a sealed system and a few on this newgroup have recommended
an ion exchange type. Does anyone have a personal experience, successful or
otherwise, with a water softener and sealed system that might influence my
choice of softener and boiler. What makes of these do you have?

The main supply water pressure at my property is 2.8 bar (measured one
February lunchtime). My wife and I have three small children, one bath, two
showers and three toilets as well as a frequently-used washing machine and
dishwasher. With the old oil-fired vented system we used to have, our water
bills show a consumption of about 200 cu.m. per year.

A difficult question I know, but can any expert out there recommend a
"dream" boiler-type/storage tank/heat exchanger so that I could start to put
together a system specification that has a good chance of working? I would
rather err on the side of buying good quality equipment than a cheap
solution.


My system:-

Man Micromat / Eco-hometec system boiler
Megaflow / Duo-tank stainless steel mains pressure hot water cylinder
EcoWater 514 Sensatronic water softener
Mixed underfloor / radiator heating system
1 Bath 2 Showers 3 Boys

Not cheap but all quality products and work well together (apart from
the boys who fight)

Nick Brooks

"John Aston" wrote in message
...
I have looked at this thread
http://tinyurl.com/3ef9x
and others on Google Groups to try and answer my questions, but found
nothing definitive.

I am renovating my house and plan to install a completely new gas-fired
central heating and hot water plumbing system. The renovation includes a
loft conversion, so I want to avoid a system that involves header tanks. I
am assuming that this means a sealed system for mains pressure hot water.

The heating system will be underfloor heating (typically 55 deg C), plus
supplementary heating (probably conventional radiators at 80 deg C flow)
for
when the weather turns really cold.

I would like to install a water softener (not a water conditioner) that is
compatible with a sealed system and a few on this newgroup have
recommended
an ion exchange type. Does anyone have a personal experience, successful
or
otherwise, with a water softener and sealed system that might influence my
choice of softener and boiler. What makes of these do you have?

The main supply water pressure at my property is 2.8 bar (measured one
February lunchtime). My wife and I have three small children, one bath,
two
showers and three toilets as well as a frequently-used washing machine and
dishwasher. With the old oil-fired vented system we used to have, our
water
bills show a consumption of about 200 cu.m. per year.

A difficult question I know, but can any expert out there recommend a
"dream" boiler-type/storage tank/heat exchanger so that I could start to
put
together a system specification that has a good chance of working? I would
rather err on the side of buying good quality equipment than a cheap
solution.

John,

Your title says combi, so..
With combi's the most important figure is the flowrate. 11 litres/min is
fine for showes and the odd slow filling bath. Here is a recent post of
mine...

For an even better flow rate and cheap too for what you get, assess using
two Worcester-Bosch Junior combi's.

For high flowrates it is cost effective to use two Juniors and combine the
DHW outlets. Worcester-Bosch will supply a drawing on how to do it, or ask
me here. Two Juniors are available for around £1000 to £1100 depending on
what sized units you buy. They have 24 and 28 kW models, you could use two
24kW or two 28 kW combi's or one of each. That is cheaper than the
Worcester HighFlow 18 litres/min floor mounted combi and can deliver about
21.5 litres/min and never run out of hot water. The highest flowrates of
any infinitely continuous combi is 22 litres/min, which is the ECO-Hometec
which costs near £2K.

Have one combi do the downstairs heating on its own programmer/timer
(Honeywell CM67 or equiv) and one do upstairs. Natural zoning, so you don't
have to heat upstairs when you are not up there saving fuel. The running
cost will be approx the same as a condensing boiler heating the whole house.
No external zone valves either, and simple wiring up too. The Juniors are
simple and don't even have internal 3-way valves.

Also if one goes down you will have another combi to give some heat in the
house and DHW too. Combine the outlets for the DHW bath pipes and all the
baths you want very quickly and no waiting. Best have the showers on
separate combi's. It will do two showers no problem at all.

The Juniors are not condensing combi's, yet overall heating costs will be
equivalent to a one condensing boiler as the upstairs will not be heated
most of the time.

A win, win, situation.

Its advantages a

- space saving (releases an airing cupboard). Both can go in the loft, or
at the back of the existing airing cupboard.
- never without heat in the house,
- high flowrates (will do two showers and fill a bath in few minutes,
- No waiting for a cylinder to re-heat
- Natural zoning, one does upstairs and one does down
- hardly any electrical control work (running a wire to a programmers/stat
and power to each,
- simple no brainer installation,
- minimal components used.
- less piping used
- cheap to run overall as upstairs would be off most of the time
- etc.

A difficult question I know, but can any expert out there recommend a
"dream" boiler-type/storage tank/heat exchanger so that I could start
to put together a system specification that has a good chance of
working?

Your main issue here is choosing a boiler that can maintain a low flow
temperature for the underfloor for efficiency reasons, whilst giving a high
temperature to the hot water system and radiators. I believe the MAN
Micromat can be set up to do this, and Andy Hall may be able to advise on
such a system.

Otherwise, you'll just need to set a high temperature and rely on the
underfloor thermostatic mixing valve to produce a low return temperature,
which may be enough for reasonable efficiency anyway. Should the Micromat's
price put you off, I'm very happy with my Worcester-Bosch Greenstar 28HE,
which is a mid-high end boiler at a much lower price.

For frequent baths and superlative multiple showers, install either an
unvented hot water cylinder (i.e. Heatrae-Sadia Megaflo) or a heat bank
system (i.e. DPS Pandora). If having it installed professionally, you'll
find more installers familiar with the unvented cylinders. However, for DIY
installation, the heat bank will be an easier job, although will require a
higher flow temperature than is optimal.

Your ion exchange water softener should be a high flow type, such as a
Kinetico 2020c HF. Whatever you buy should be metered, not timed.

Christian.

"Nick Brooks" wrote in message
...
John Aston wrote:

snip

A difficult question I know, but can any expert out there recommend a
"dream" boiler-type/storage tank/heat exchanger so that I could start to
put
together a system specification that has a good chance of working? I
would
rather err on the side of buying good quality equipment than a cheap
solution.


My system:-

Man Micromat / Eco-hometec system boiler
Megaflow / Duo-tank stainless steel mains pressure hot water cylinder
EcoWater 514 Sensatronic water softener
Mixed underfloor / radiator heating system
1 Bath 2 Showers 3 Boys

Not cheap but all quality products and work well together (apart from
the boys who fight)

Nick Brooks

Thanks, Nick. I am assuming that you got Eco-hometec to do the design. May I
ask if you were pleased with their competence and response? I'm thinking of
going to them for a quote.

Did they install the system as well?

"Christian McArdle" wrote in message
et...

Your main issue here is choosing a boiler that can maintain a low flow
temperature for the underfloor for efficiency reasons, whilst giving a
high
temperature to the hot water system and radiators. I believe the MAN
Micromat can be set up to do this, and Andy Hall may be able to advise on
such a system.

Is the Micromat a condensing boiler? I've traced the manufacturer's website
(http://www.man-heiztechnik.de/_html/...e/micromat.php) but all the
information is in German.

From what I read on this newsgroup, the condensing boiler will not operate
at its best efficiency if it has to heat water up to the temperature
required for conventional radiators. Any way around this for a mixed
underfloor/radiator solution? (Other than doubling the size of the rads!)

On Thu, 15 Apr 2004 23:48:30 +0100, "John Aston"
wrote:




Thanks, Nick. I am assuming that you got Eco-hometec to do the design. May I
ask if you were pleased with their competence and response? I'm thinking of
going to them for a quote.

Did they install the system as well?


I'll throw something in here John.

Eco Hometec are a distributor for MAN Heiztechnik (part of the MAN BW
company that make the big diesel engines and trucks) based in Hamburg

http://www.man-heiztechnik.de/index_e.php

The other is MHS Boilers and both sell the Micromat EC product.

I researched good quality boilers a year and a bit ago and shortlisted
to this one, Keston, Viessmann and a couple of others.
My main issues were build quality, specification, reliability, spares
availability, technical support etc.

I put together a very detailed questionnaire and emailed it to each
supplier. I also contacted MAN Heiztechnik in Germany and spoke to
their technical department and to a product manager, specifically on
how they are selling the product. It is a high end boiler, no
question, and that is reflected in the price - north of £1k.

I received a somewhat satisfactory reply from Keston and from
Viessmann but the one from Eco Hometec was much more detailed and
they answered every question. I had asked things like the prices for
the six most expensive spare parts and so on. Frankly they did a
lot of work to answer my questions that the others didn't bother to
do.

I also checked out Eco Hometec's filing at the Registrar of Companies
and they are not large, but I felt set up adequately to address what
they are doing.
They specialise in the selfbuild and discerning markets and sell
directly to the end user or installer, not through plumbing and
heating merchants.
I visited their place in Doncaster - on an industrial estate on the
edge of town. I guess that they employ around 15-20 people
including service engineers in different parts of the country.
There is a demo room set up with all of the boiler types that they
sell and you can see any of them in operation - they'll show the
components and how it all goes together etc.

The Micromat is an extremely well engineered and solid machine made
from quality components. There was no comparison to the Glow Worm
that was installed before and ended up in the skip not long
afterwards.

In terms of design, I didn't need a lot of help apart from figuring
out the correct setting for the boiler controller to drive the
motorised valve setup that I have.

I did the installation except for the commissioning and everything
else went smoothly.

I don't think that they will do complete installations but may
organise someone for you. I believe that they do do designs including
UFH if you want it. I'm pretty sure that they won't attempt to do
things beyond their ability.

In terms of purchasing, this was uneventful as well. The questions
were answered, and I deliberated for several months. They called me
on an agreed basis each month to follow up any issues and then quoted
- didn't hassle me for the order.

If you are going for a HW cylinder, I would recommend getting one with
a pocket for a temperature probe and getting the probe accessory for
the boiler. This gives much better control of the hot water
temperature and reheating than a cylinder thermostat does.
The outside temperature sensor is included with the boiler.


I'd certainly buy the same boiler again and from them, so certainly
I'd ask for a quote and ask your other questions.

..andy

To email, substitute .nospam with .gl

On Fri, 16 Apr 2004 00:19:06 +0100, "John Aston"
wrote:


"Christian McArdle" wrote in message
. net...

Your main issue here is choosing a boiler that can maintain a low flow
temperature for the underfloor for efficiency reasons, whilst giving a
high
temperature to the hot water system and radiators. I believe the MAN
Micromat can be set up to do this, and Andy Hall may be able to advise on
such a system.

Is the Micromat a condensing boiler? I've traced the manufacturer's website
(http://www.man-heiztechnik.de/_html/...e/micromat.php) but all the
information is in German.

There's an English section if you go to

http://www.man-heiztechnik.de/index_e.php

Look for the Micromat, and yes it is condensing.



From what I read on this newsgroup, the condensing boiler will not operate
at its best efficiency if it has to heat water up to the temperature
required for conventional radiators.

Yes and no.

You size radiators to meet the worst case heat loss - ie. a cold
winter's night. With a non-condensing boiler, this is done at 82
flow, 70 return.

A condensing boiler's efficiency increases with reducing return
temperature. When the dew point around 54 degrees is reached, the
graph of efficiency vs. temperature shows a knee in the curve and the
efficiency increases at a greater rate below this as condensing
happens. It is not correct to say that there is a sudden step change
in condensing mode - purely a rate of change - so 53.5 is not hugely
better than 54.5

When the weather is warmer, the weather compensator sensor causes the
flow temperature and return temperature to be reduced by reducing the
boiler burn rate and pump speed. Thus it will be working at higher
efficiency anyway.

If you size the radiators larger, you can run the flow at a top
temperature of 70 (return 50) and the boiler will modulate down
further. Therefore it is true to say that it will generally be more
efficient.


Any way around this for a mixed
underfloor/radiator solution? (Other than doubling the size of the rads!)


I replied to your email and basically I think you could do three
scenarios.

- 85 degree radiator design and UFH connected using a blending valve

- 70 degree radiator design and UFH via blending valve

- 50 degree for both. However, the radiators would then be quite
large.


..andy

To email, substitute .nospam with .gl

"John Aston" wrote in message t...
snip
Thanks, Nick. I am assuming that you got Eco-hometec to do the design. May I
ask if you were pleased with their competence and response? I'm thinking of
going to them for a quote.

Did they install the system as well?

Eco hometec did specify the boiler and tank as well as the UFH design
and although their service was generally ok I wouldn't use them again.
The reason for this is that I have learnt a lot more about heating
from this group in the last year and it is possible to buy an
identical system for MUCH less if you shop around
Having said that you do get the peace of mind that everything will be
appropriately sized and there is a good chance it will all work
together

Nick Brooks

"Nick Brooks" wrote in message
om...
"John Aston" wrote in message
t...
snip
Thanks, Nick. I am assuming that you got Eco-hometec to do the design.
May I
ask if you were pleased with their competence and response? I'm thinking
of
going to them for a quote.

Did they install the system as well?

Eco hometec did specify the boiler and tank as well as the UFH design
and although their service was generally ok I wouldn't use them again.
The reason for this is that I have learnt a lot more about heating
from this group in the last year and it is possible to buy an
identical system for MUCH less if you shop around

Nick, what would you suggest to John as an alternative?