Solar water heating and combi boilers
 

I have been investigating installing a solar water heating system that I
wanted by use to provide pre-heated water to my combi ("the warmer the water
feed, the less gas used to heat it" principle). I have spoken with a number
of suppliers of Solar thermal systems and some say its possible whilst
others say it will damage the combi. What is the "truth" here?

Solar water heating and combi boilers
 

On Sun, 14 May 2006 10:13:41 +0100 someone who may be "Keith D"
wrote this:-

I have been investigating installing a solar water heating system that I
wanted by use to provide pre-heated water to my combi ("the warmer the water
feed, the less gas used to heat it" principle). I have spoken with a number
of suppliers of Solar thermal systems and some say its possible whilst
others say it will damage the combi. What is the "truth" here?

The truth is that it depends on the combination boiler. Some will
cope with heated water at the inlet others will not.

Depending on the answer to the obvious question there are then a
range of options, depending on the house layout, hot water demand,
condition of the boiler and determination.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

Solar water heating and combi boilers
 

"Keith D" wrote in message
...
I have been investigating installing a solar water heating system that I
wanted by use to provide pre-heated water to my combi ("the warmer the
water feed, the less gas used to heat it" principle). I have spoken with a
number of suppliers of Solar thermal systems and some say its possible
whilst others say it will damage the combi. What is the "truth" here?

I can't understand why you want to do that. Water from the solar system is
warm or hot enough for most tasks on most days. If it needs a boost you can
provide that from your programmer.

That's our experience, not theory.

Mary

Solar water heating and combi boilers
 

On Sun, 14 May 2006 10:13:41 +0100, Keith D wrote:

I have been investigating installing a solar water heating system that I
wanted by use to provide pre-heated water to my combi ("the warmer the water
feed, the less gas used to heat it" principle). I have spoken with a number
of suppliers of Solar thermal systems and some say its possible whilst
others say it will damage the combi. What is the "truth" here?

Solar and combis are an awkward combination. It's do-able but probably
expensive.

But before going further may I ask:
1: is your house already draught-proofed and insulated to the highest
standards
2: does your heating system already have thermostatic radiator
valves, a programmable thermostats and - if the house is not absolutely
tiny - separate heating zones
3: is your combi already a high-efficiency condensing type?

If the answer to any of these questions is No then improving the relevant
area(s) is likely to make more sense both economically and ecologically
than spending £1000s on a solar water heating system.

Solar water heating and combi boilers
 

Mary Fisher wrote:

I can't understand why you want to do that. Water from the solar system is
warm or hot enough for most tasks on most days. If it needs a boost you can
provide that from your programmer.

How would you achieve this "boost" without a hot water cylinder?


--
Cheers,

John.

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

Solar water heating and combi boilers
 

"John Rumm" wrote in message
...
Mary Fisher wrote:

I can't understand why you want to do that. Water from the solar system
is warm or hot enough for most tasks on most days. If it needs a boost
you can provide that from your programmer.

How would you achieve this "boost" without a hot water cylinder?

You do have a cylinder. It's not a problem :-) The OP didn't say that he
didn't have one.

Mary

Solar water heating and combi boilers
 

On Sun, 14 May 2006 16:46:39 +0100, Mary Fisher wrote:

You do have a cylinder. It's not a problem :-) The OP didn't say that he
didn't have one.

He said he has a combi which means that he doesn't have a cylinder.
So it is a problem :-)

Solar water heating and combi boilers
 

"John Stumbles" wrote in message
...
On Sun, 14 May 2006 16:46:39 +0100, Mary Fisher wrote:

You do have a cylinder. It's not a problem :-) The OP didn't say that he
didn't have one.

He said he has a combi which means that he doesn't have a cylinder.

No it doesn't!

Solar water heating and combi boilers
 

Mary Fisher wrote:

"John Stumbles" wrote in message
...

On Sun, 14 May 2006 16:46:39 +0100, Mary Fisher wrote:


You do have a cylinder. It's not a problem :-) The OP didn't say that he
didn't have one.

He said he has a combi which means that he doesn't have a cylinder.


No it doesn't!

OK then, it means he *probably* does not have a cylinder. Better?

--
Cheers,

John.

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

Solar water heating and combi boilers
 

"John Rumm" wrote in message
...
Mary Fisher wrote:

"John Stumbles" wrote in message
...

On Sun, 14 May 2006 16:46:39 +0100, Mary Fisher wrote:


You do have a cylinder. It's not a problem :-) The OP didn't say that he
didn't have one.

He said he has a combi which means that he doesn't have a cylinder.


No it doesn't!

OK then, it means he *probably* does not have a cylinder. Better?

Whatever

--
Cheers,

John.

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

Solar water heating and combi boilers
 

On Sun, 14 May 2006 16:43:29 GMT someone who may be John Stumbles
wrote this:-

He said he has a combi which means that he doesn't have a cylinder.

I know people that do. The combination boiler provides hot water to
the kitchen, while a cylinder provides decent amounts of hot water
for showers and baths.

Other than small houses with compact services, a variety of sources
of hot water are often the best approach.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

Solar water heating and combi boilers
 

On Sun, 14 May 2006 14:23:09 GMT someone who may be John Stumbles
wrote this:-

But before going further may I ask:
1: is your house already draught-proofed and insulated to the highest
standards

Cavity wall and loft insulation, to the greatest extent possible are
certainly important, as well as cost-effective draught-proofing.
Important for reducing heating costs.

However, none of these affect hot water production to any extent.
What matters is the layout of the house and the services within it.
Insulation of the hot water pipes is certainly a good move in many
circumstances.

2: does your heating system already have thermostatic radiator
valves, a programmable thermostats and - if the house is not absolutely
tiny - separate heating zones

Important for reducing heating costs.

3: is your combi already a high-efficiency condensing type?

If it is not I would ask questions about how old it is. Replacing a
relatively new boiler is not sound financially or environmentally.

If the answer to any of these questions is No then improving the relevant
area(s) is likely to make more sense both economically and ecologically
than spending £1000s on a solar water heating system.

Economically solar water heating is still a long term investment, at
current fuel prices. However, the price of sunshine is not going to
increase, unlike other fuels. There are also other advantages, such
as being able to largely turn the boiler off in summer and thus
(probably) prolonging its life. If it is the sort of combination
boiler that has a small hot water cylinder this will also save some
gas.

Environmentally solar water heating is an excellent investment.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

Solar water heating and combi boilers
 

"David Hansen" wrote in message
...

Environmentally solar water heating is an excellent investment.

I agree. I wish we'd done it years ago.

Mary

Solar water heating and combi boilers
 

Keith D wrote:
I have been investigating installing a solar water heating system that I
wanted by use to provide pre-heated water to my combi ("the warmer the water
feed, the less gas used to heat it" principle). I have spoken with a number
of suppliers of Solar thermal systems and some say its possible whilst
others say it will damage the combi. What is the "truth" here?

Here's one solution
http://www.eco-hometec.co.uk/ecosol3.htm
But their boilers are about twice the price of everything else on the
market.


--
http://gymratz.co.uk - Best Gym Equipment & Bodybuilding Supplements UK.
http://trade-price-supplements.co.uk - TRADE PRICED SUPPLEMENTS for ALL!
http://fitness-equipment-uk.com - UK's No.1 Fitness Equipment Suppliers.
http://Water-Rower.co.uk - Worlds best prices on the Worlds best Rower.

Solar water heating and combi boilers
 

yes to all of them
"John Stumbles" wrote in message
.. .
On Sun, 14 May 2006 10:13:41 +0100, Keith D wrote:

I have been investigating installing a solar water heating system that I
wanted by use to provide pre-heated water to my combi ("the warmer the
water
feed, the less gas used to heat it" principle). I have spoken with a
number
of suppliers of Solar thermal systems and some say its possible whilst
others say it will damage the combi. What is the "truth" here?

Solar and combis are an awkward combination. It's do-able but probably
expensive.

But before going further may I ask:
1: is your house already draught-proofed and insulated to the highest
standards
2: does your heating system already have thermostatic radiator
valves, a programmable thermostats and - if the house is not absolutely
tiny - separate heating zones
3: is your combi already a high-efficiency condensing type?

If the answer to any of these questions is No then improving the relevant
area(s) is likely to make more sense both economically and ecologically
than spending £1000s on a solar water heating system.

Solar water heating and combi boilers
 

On Mon, 15 May 2006 20:15:35 +0100, Keith D wrote:

"John Stumbles" wrote in message
.. .

... before going further may I ask:
1: is your house already draught-proofed and insulated to the highest
standards
2: does your heating system already have thermostatic radiator
valves, a programmable thermostats and - if the house is not absolutely
tiny - separate heating zones
3: is your combi already a high-efficiency condensing type?

yes to all of them

OK, good boy ;-)

I that case you may want to investigate thermal store/heat bank
systems to store the heat from the solar system. One arrangement that
suggests itself to me it to have the store supply hot water (at mains
pressure) directly to taps when the water is hot enough, and to use it
as input to the combi when it's too cool to use directly.

However, depending on the design of the combi you may still be limited to
the lower rate of flow that it can provide even though it's having to do
less work, given pre-heated incoming water. A configuration that might
give better flow might be to combine the output of the thermal store
with the output of the combi via a thermostatic mixing valve: combi to hot
input and combi to cold input of the valve. Again you'd only want this
in-circuit when the store can't supply hot enough water.

In each case I guess you might use a 2-port or 3-port motorised valve to
bypass the combi, controlled by a thermostat sensing the temperature of
the store. Although these valves are only intended for closed systems with
corrosion inhibitor they usually have brass bodies and some sort of rubber
(EPDM?) actuator ball which should be OK (if not strictly kosher in terms
of water regs and WRAS approval) for DHW.

Is your solar system going to be low or hi tech? E.g. old radiators in
glass boxes or evacuated tubes. Depending on how much you're spending
there are ways of DIY-ing thermal stores at low cost.

Solar water heating and combi boilers
 

On Mon, 15 May 2006 17:44:25 GMT, "Pet @ www.gymratz.co.uk ;¬)"
wrote:


Here's one solution
http://www.eco-hometec.co.uk/ecosol3.htm
But their boilers are about twice the price of everything else on the
market.

Anything with "Eco" in it is several times the price of everything
else on the market.

--
Peter Parry.
http://www.wpp.ltd.uk/

Solar water heating and combi boilers
 

On Mon, 15 May 2006 12:21:18 +0100, David Hansen
wrote:


Economically solar water heating is still a long term investment, at
current fuel prices.

Actually it is a long term non-investment as in most cases, and all
commercially installed and maintained systems, it will never even
break even.

There are also other advantages, such
as being able to largely turn the boiler off in summer and thus
(probably) prolonging its life.

There is no evidence that this is the case at all, and in all
probability it will almost certainly reduce its life as seals and
bearings in pumps and valves really dislike being unused for months
on end and corrosion will also worsen.

Environmentally solar water heating is an excellent investment.

In propaganda.


--
Peter Parry.
http://www.wpp.ltd.uk/

Solar water heating and combi boilers
 

On Mon, 15 May 2006 23:36:55 +0100 someone who may be Peter Parry
wrote this:-

Economically solar water heating is still a long term investment, at
current fuel prices.

Actually it is a long term non-investment as in most cases, and all
commercially installed and maintained systems, it will never even
break even.

At current prices DIY systems are long term investments. Systems
where one pays someone to install it are probably not going to break
even at current prices, but note the name of this newsgroup and that
the price of sunshine is not going to increase, unlike other fuels.

There are also other advantages, such
as being able to largely turn the boiler off in summer and thus
(probably) prolonging its life.

There is no evidence that this is the case at all,

Incorrect.

and in all
probability it will almost certainly reduce its life as seals and
bearings in pumps

Pumps should indeed be turned over occasionally. However, that has
no bearing on the life of the boiler.

and valves really dislike being unused for months on end

No bearing on the life of the boiler either.

and corrosion will also worsen.

Corrosion where?

Environmentally solar water heating is an excellent investment.

In propaganda.

Incorrect. As I pointed out and you snipped, it can save more gas
than people think.

You can keep trying with your incorrect assertions for as long as
you like. However, because somebody may believe you, they will be
rebutted whenever necessary.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

Solar water heating and combi boilers
 

"Peter Parry" wrote in message
...
On Mon, 15 May 2006 12:21:18 +0100, David Hansen
wrote:


Economically solar water heating is still a long term investment, at
current fuel prices.

Actually it is a long term non-investment as in most cases, and all
commercially installed and maintained systems, it will never even
break even.

You don't support that statement but in any case you're only talking about
the effect on the buyer's pocket. There are other considerations.

Mary

Solar water heating and combi boilers
 

Peter Parry wrote:

Anything with "Eco" in it is several times the price of everything
else on the market.

:¬)

Likewise with "organic"

--
http://gymratz.co.uk - Best Gym Equipment & Bodybuilding Supplements UK.
http://trade-price-supplements.co.uk - TRADE PRICED SUPPLEMENTS for ALL!
http://fitness-equipment-uk.com - UK's No.1 Fitness Equipment Suppliers.
http://Water-Rower.co.uk - Worlds best prices on the Worlds best Rower.

Solar water heating and combi boilers
 

""Pet @ www.gymratz.co.uk ;¬)"" wrote in message
. uk...
Peter Parry wrote:

Anything with "Eco" in it is several times the price of everything
else on the market.

:¬)

Likewise with "organic"

Not true.

Solar water heating and combi boilers
 

On Tue, 16 May 2006 08:36:11 +0100, David Hansen
wrote:

On Mon, 15 May 2006 23:36:55 +0100 someone who may be Peter Parry
wrote this:-

Actually it is a long term non-investment as in most cases, and all
commercially installed and maintained systems, it will never even
break even.

At current prices DIY systems are long term investments. Systems
where one pays someone to install it are probably not going to break
even at current prices, but note the name of this newsgroup and that
the price of sunshine is not going to increase, unlike other fuels.

If it proves popular what's the betting ownership of it will get
taxed (indeed the mechanism for doing so has already been put in
place by Nulabor) :-).

There are also other advantages, such
as being able to largely turn the boiler off in summer and thus
(probably) prolonging its life.

There is no evidence that this is the case at all,

Incorrect.

I'd be interested in seeing any. The only mentions I have found are
unsubstantiated statements usually made by peddlers of solar
fittings.

and in all
probability it will almost certainly reduce its life as seals and
bearings in pumps

Pumps should indeed be turned over occasionally. However, that has
no bearing on the life of the boiler.

and valves really dislike being unused for months on end

No bearing on the life of the boiler either.

Both have bearing on the life of the "conventional" system and hence
the economics of solar water heating. In many boilers the pumps and
control valves are integrated within the boiler.

and corrosion will also worsen.

Corrosion where?

The boiler casing. It is a fairly common cause of terminal failure
of room sealed boilers.

Environmentally solar water heating is an excellent investment.

In propaganda.

Incorrect. As I pointed out and you snipped, it can save more gas
than people think.

I snipped the bits about saving energy (which I agree is a far more
sensible starting point and applicable no matter what system is used)
but didn't see anything about how solar heating can save more gas
than people think.

You can keep trying with your incorrect assertions for as long as
you like. However, because somebody may believe you, they will be
rebutted whenever necessary.

So will unsubstantiated and incorrect claims for solar water heating
making economic sense. People may buy it for other reasons not all
of which may be altogether objective and that is their free choice.
What is wrong is to claim it makes _economic_ sense when quite
plainly in the vast majority of cases it doesn't (which of course is
exactly why the proponents of it always studiously avoid using
figures).

For example the oft quoted solution of the solar powered motor pumped
panels on the direct side of the water system makes great claims
about the economic sense of doing this (saving the few watts an
electric pump takes) but makes little or no mention of the fact that
for most people living east of a line drawn roughly from Lincoln to
Bristol you also need to install an ion exchange water softener
otherwise the panel will quickly be ruined because of scale from the
hard water.


--
Peter Parry.
http://www.wpp.ltd.uk/

Solar water heating and combi boilers
 

"Peter Parry" wrote in message
...
On Tue, 16 May 2006 08:36:11 +0100, David Hansen
wrote:

On Mon, 15 May 2006 23:36:55 +0100 someone who may be Peter Parry
wrote this:-

Actually it is a long term non-investment as in most cases, and all
commercially installed and maintained systems, it will never even
break even.

At current prices DIY systems are long term investments. Systems
where one pays someone to install it are probably not going to break
even at current prices, but note the name of this newsgroup and that
the price of sunshine is not going to increase, unlike other fuels.

If it proves popular what's the betting ownership of it will get
taxed (indeed the mechanism for doing so has already been put in
place by Nulabor) :-).

There are also other advantages, such
as being able to largely turn the boiler off in summer and thus
(probably) prolonging its life.

There is no evidence that this is the case at all,

Incorrect.

I'd be interested in seeing any. The only mentions I have found are
unsubstantiated statements usually made by peddlers of solar
fittings.

You haven't given any evidence of your claims.

Solar water heating and combi boilers
 

Mary Fisher wrote:

You haven't given any evidence of your claims.

Well, let us get some...

How much did your solar system cost in total?


--
Cheers,

John.

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

Solar water heating and combi boilers
 

"John Rumm" wrote in message
...
Mary Fisher wrote:

You haven't given any evidence of your claims.

Well, let us get some...

How much did your solar system cost in total?

No, dear, he's supposed to be providing the 'evidence'.

Solar water heating and combi boilers
 

What did your system cost to have installed? And what does it consist of?

Why do you want to know?

Solar water heating and combi boilers
 

John Rumm wrote:

Mary Fisher wrote:

You haven't given any evidence of your claims.


Well, let us get some...

How much did your solar system cost in total?

I will let him do that, but my question still stands if you don't mind
me asking?

What did your system cost to have installed? And what does it consist of?

--
Cheers,

John.

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

Solar water heating and combi boilers
 

Mary Fisher wrote:

What did your system cost to have installed? And what does it consist of?


Why do you want to know?

Because I am curious obviously!

Solar systems seem to vary from those essentially assembled from scrap
(old radiators and yards of black MDPE pipe etc), to very high tech
vacuum tube based collector systems run by sophisticated digital
controllers. You have posted in the past about how your system performs,
but that only gives us half the story without us also knowing what
components it is made from, or what its capital cost was.


--
Cheers,

John.

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

Solar water heating and combi boilers
 

"John Rumm" wrote in message
...
Mary Fisher wrote:

What did your system cost to have installed? And what does it consist of?


Why do you want to know?

Because I am curious obviously!

Solar systems seem to vary from those essentially assembled from scrap
(old radiators and yards of black MDPE pipe etc), to very high tech vacuum
tube based collector systems run by sophisticated digital controllers. You
have posted in the past about how your system performs, but that only
gives us half the story without us also knowing what components it is made
from, or what its capital cost was.

I have also given the url.

Far be it from me to be accused of advertising so I shan't do it again.

Most people seem to think that the payback time is the most important aspect
of such installations. We don't (we don't consider the payback time on
anything else we buy either) but for those people we've worked out that on
present gas prices we'll recover the cost in ten years (if we live that
long). I doubt that present gas prices won't stay what they are so nobody
can determine what the payback time will be.

Nobody.

That includes you and Parry and all the other sceptics.

Mary

Solar water heating and combi boilers
 

On Tue, 16 May 2006 21:31:55 +0100, John Rumm wrote:

Solar systems seem to vary from those essentially assembled from scrap
(old radiators and yards of black MDPE pipe etc), to very high tech
vacuum tube based collector systems run by sophisticated digital
controllers. You have posted in the past about how your system performs,
but that only gives us half the story without us also knowing what
components it is made from, or what its capital cost was.

FWIW, prices have been dropping fast recently. I've picked up a 300 litre
20 vacuum tube unit for the tractor shed/store at the farm. We're
installing a bathroom/office at the back of the store and the only source
of hot water will be solar. The total cost of the unit + installation is
£700, cheaper than an LPG system.

Solar water heating and combi boilers
 

On Mon, 15 May 2006 21:48:54 +0000, John Stumbles wrote:

... A configuration that might
give better flow might be to combine the output of the thermal store
with the output of the combi via a thermostatic mixing valve: combi to hot
input and combi to cold input of the valve. Again you'd only want this
in-circuit when the store can't supply hot enough water.

Mains pressure
hot/warm water ---------
from thermal store | combi |
------------------+---| DHW |------
| --------- |
| -----
| | H |
| | TMV |-------
| | C |
| -----
| |
---------------------


... you might use a 2-port or 3-port motorised valve to
bypass the combi, controlled by a thermostat sensing the temperature of
the store.

Actually, thinking about it, the arrangement above may just work (or
Just Work (tm) :-)) without faffing about with thermostats, motorised
valves etc. As long as the temperature of water from the store is above
the TMV's set point it'll only draw water from its Cold inlet i.e.
directly from the store. Only when the water gets too cool will it draw
from its Hot inlet which should automatically kick in the combi.

Note that in this case the TMV is not limiting the temperature of DHW
which could possibly get dangerously high when the solar system is working
well, so you may want another TMV mixing the output with cold water from
the main.

Solar water heating and combi boilers
 

On Tue, 16 May 2006 20:49:08 +0100, John Rumm wrote:

What did your system cost to have installed? And what does it consist of?

Hint: google for fisher and solartwin :-)
http://tinyurl.com/owxpl

They're about £1500 to buy.

Solar water heating and combi boilers
 

On Tue, 16 May 2006 17:18:10 +0100, Peter Parry wrote:

For example the oft quoted solution of the solar powered motor pumped
panels on the direct side of the water system makes great claims
about the economic sense of doing this (saving the few watts an
electric pump takes) but makes little or no mention of the fact that
for most people living east of a line drawn roughly from Lincoln to
Bristol you also need to install an ion exchange water softener
otherwise the panel will quickly be ruined because of scale from the
hard water.

I'd have thought a (much cheaper) phosphor-dosing scale inhibitor would
serve this purpose, as it does for other water-heating appliances such as
combi boilers. Do you have some evidence to show that this is not the
case?

Solar water heating and combi boilers
 

Mary Fisher wrote:
What did your system cost to have installed? And what does it consist of?

Why do you want to know?

If you're going to snip, and I commend you for this new
departure, please do it properly. Some actual info. instead
of simple trolling would be nice, too.

Solar water heating and combi boilers
 

On Tue, 16 May 2006 17:39:46 +0100, "Mary Fisher"
wrote:


"Peter Parry" wrote

I'd be interested in seeing any. The only mentions I have found are
unsubstantiated statements usually made by peddlers of solar
fittings.

You haven't given any evidence of your claims.

That turning boilers off for weeks or months on end causes harm? Ask
your local plumber. Failing that look at the pattern of repairs that
one user of this group who fixes such things by the thousand has
reported in the past - each autumn the spares consumption increases
dramatically as boilers come on after summer and pumps, valves and
PCB's fail.

If you want a more academic treatise Failure Modes Effects Analysis
by Palady discuses failure modes effects and criticality. Shafts
bind to bearings if not used - Machinerys Handbook (every edition
since the beginning of the last century).

It is simple basic mechanics. There is ample evidence that lack of
use shortens life and causes harm in devices such as boilers. There
is none at all that not using them for some months every year does
them good or extends their working life.



--
Peter Parry.
http://www.wpp.ltd.uk/

Solar water heating and combi boilers
 

In message , Peter Parry
writes
On Tue, 16 May 2006 17:39:46 +0100, "Mary Fisher"
wrote:


"Peter Parry" wrote

I'd be interested in seeing any. The only mentions I have found are
unsubstantiated statements usually made by peddlers of solar
fittings.

You haven't given any evidence of your claims.

That turning boilers off for weeks or months on end causes harm? Ask
your local plumber. Failing that look at the pattern of repairs that
one user of this group who fixes such things by the thousand has
reported in the past - each autumn the spares consumption increases
dramatically as boilers come on after summer and pumps, valves and
PCB's fail.

And he's still waiting for someone in uk.d-i-y to return a fan ...



If you want a more academic treatise Failure Modes Effects Analysis
by Palady discuses failure modes effects and criticality. Shafts
bind to bearings if not used - Machinerys Handbook (every edition
since the beginning of the last century).

It is simple basic mechanics. There is ample evidence that lack of
use shortens life and causes harm in devices such as boilers. There
is none at all that not using them for some months every year does
them good or extends their working life.




--
geoff

Solar water heating and combi boilers
 

In message , John
Rumm writes
John Rumm wrote:

Mary Fisher wrote:

You haven't given any evidence of your claims.
Well, let us get some...
How much did your solar system cost in total?

I will let him do that, but my question still stands if you don't mind
me asking?

What did your system cost to have installed? And what does it consist of?

You're going to embarrass her now

She's meant to be a frugal oop north lass - having bought a pig in a
poke isn't going to go down too well

--
geoff

Solar water heating and combi boilers
 

In message , Mary Fisher
writes


What did your system cost to have installed? And what does it consist of?

Why do you want to know?

To see who else other than "spouse" has gefooked you
--
geoff

Solar water heating and combi boilers
 

On Tue, 16 May 2006 17:18:10 +0100, Peter Parry wrote:

you also need to install an ion exchange water softener
otherwise the panel will quickly be ruined because of scale from the
hard water.

Say what? The water in the panel should be recirculated and contain rust
and scale inhibitors (as in a primary boiler circuit). The heat should be
transferred to a separate hot water cylinder of exactly the same type as is
used on non-solar systems.