Do any of you consider combi boilers and sealed systems a false
economy? I installed my system ten years ago. Since then, I have had
to spend about £100 a year just maintaining the boiler! My boiler
(Chaffateaux Britony 80) has given problems of one sort or another
about once a year, on average, and the parts are not cheap.

Then there are the other disadvantages associated with combis too..

I'm seriously wondering if I'd save money by ripping the boiler out
and installing a conventional boiler with header tank etc... (It's a
three bed semi).

Or, I could use the combi boiler as a conventional boiler... Would
that be feasable? Then some of the components wouldn't get used (the
diverter valve, the secondary heat exchanger, etc) so they would never
play up!

Thanks,

Jim D

Jim D wrote:
Do any of you consider combi boilers and sealed systems a false
economy? I installed my system ten years ago. Since then, I have had
to spend about £100 a year just maintaining the boiler! My boiler
(Chaffateaux Britony 80) has given problems of one sort or another
about once a year, on average, and the parts are not cheap.

Then there are the other disadvantages associated with combis too..

I'm seriously wondering if I'd save money by ripping the boiler out
and installing a conventional boiler with header tank etc... (It's a
three bed semi).

Or, I could use the combi boiler as a conventional boiler... Would
that be feasable? Then some of the components wouldn't get used (the
diverter valve, the secondary heat exchanger, etc) so they would never
play up!

I suspect that you'd have just as many problems with a modern
non-combi.

what problems have you had so far? are the faults connected, somehow?

harry

"Mr Harry" wrote in message
oups.com...

Jim D wrote:
Do any of you consider combi boilers and sealed systems a false
economy? I installed my system ten years ago. Since then, I have had
to spend about £100 a year just maintaining the boiler! My boiler
(Chaffateaux Britony 80) has given problems of one sort or another
about once a year, on average, and the parts are not cheap.

Then there are the other disadvantages associated with combis too..

I'm seriously wondering if I'd save money by ripping the boiler out
and installing a conventional boiler with header tank etc... (It's a
three bed semi).

Or, I could use the combi boiler as a conventional boiler... Would
that be feasable? Then some of the components wouldn't get used (the
diverter valve, the secondary heat exchanger, etc) so they would never
play up!

I suspect that you'd have just as many problems with a modern
non-combi.

what problems have you had so far? are the faults connected, somehow?

harry

Had a back boiler here since 1982 and it has not once given any real trouble
apart from one thermocouple that took 2mins to change. Very reliable and
cheap to run too.
I wouldn't have a combination boiler, no gas fitter I know recommends them
for the very reasons stated. Crap quality, always breaking down and
unreliable.

Jim D wrote:
Do any of you consider combi boilers and sealed systems a false
economy? I installed my system ten years ago. Since then, I have had
to spend about £100 a year just maintaining the boiler! My boiler
(Chaffateaux Britony 80) has given problems of one sort or another
about once a year, on average, and the parts are not cheap.

snip

I've a 15 year old combi in my house that is ticking along just fine and
hasn't cost me a penny. Touch wood!

On Mon, 16 Oct 2006 20:06:43 +0100, Jim D wrote:


Do any of you consider combi boilers and sealed systems a false
economy? I installed my system ten years ago. Since then, I have had
to spend about £100 a year just maintaining the boiler! My boiler
(Chaffateaux Britony 80) has given problems of one sort or another
about once a year, on average, and the parts are not cheap.

Then there are the other disadvantages associated with combis too..

I'm seriously wondering if I'd save money by ripping the boiler out
and installing a conventional boiler with header tank etc... (It's a
three bed semi).

Or, I could use the combi boiler as a conventional boiler... Would
that be feasable? Then some of the components wouldn't get used (the
diverter valve, the secondary heat exchanger, etc) so they would never
play up!

Firstly, have you read the BoilerChoice FAQ?

Realistically: I own or am personally responsible for 2 conventional and 3
combi boilers.

My experience is as follows:
Combi 1. Vaillant Turbomax. 5 years. 1 DHW flow micro switch.
Combi 2. Vaillant Turbomax+. 3 years. 1 inexplicable electronics lockout,
reset and no further troubles.
Previously Alde 7kW (sic) storage combi. During 5 years 2 fans.
but replaced due to increasingly inadequate HW production.

Combi 3. Vaillant Sine (about 20 y.o.). 8 years. 1 t/couple.
1 overhaul of DHW diaphragm assy.

Boiler 1. Potterton Profile 30e. (about 15 y.o.) 6 years. 1 pump.
Boiler 2. Keston C25. (2.5 years) 1 gas valve, replaced before it went
down "hard".

Have I been exceptionally fortunate? I don't think so.

--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html
Gas Fitting Standards Docs he http://www.makewrite.demon.co.uk/GasFittingStandards

Jim D wrote:

Do any of you consider combi boilers and sealed systems a false
economy? I installed my system ten years ago. Since then, I have had

No, but many budget boilers of any type, are a false economy...

to spend about £100 a year just maintaining the boiler! My boiler
(Chaffateaux Britony 80) has given problems of one sort or another
about once a year, on average, and the parts are not cheap.

Then there are the other disadvantages associated with combis too..

I'm seriously wondering if I'd save money by ripping the boiler out
and installing a conventional boiler with header tank etc... (It's a
three bed semi).

Most boilers, be they conventional or combi, will use a sealed system
these days. There are a few about that will run vented, but sealed
systems are usually thought of as better by most people. They still have
their own unique problems, as do vented systems.

Or, I could use the combi boiler as a conventional boiler... Would
that be feasable?

It would certainly.

Then some of the components wouldn't get used (the
diverter valve, the secondary heat exchanger, etc) so they would never
play up!

True...

However you may find doing both will give you the best availability from
it. e.g. have the combi side feed a single shower where the mains
pressure will be an advantage, and have the CH system feed a
conventional cylinder via an external diversion valve for rapid delivery
of high volumes of hot water to baths etc.

You don't really eliminate the problems of a valve failing in either
case - you just move where it is and allow use of a generic replacement
part rather than a manufactuer specific one.

The days of low tech fit and forget cast iron monsters however are over
- whatever you buy is going to be stuffed full of clever stuff to try
and avoid throwing sizeable chunks of your money out of the flue.

--
Cheers,

John.

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

Jim D wrote:
Do any of you consider combi boilers and sealed systems a false
economy? snip

I'm not an expert on this, so take what I say with a pinch of salt!
I've just replaced an oil combi (Worcester HeatSlave 16) with a new
Condensing Oil boiler (Mistral 50-90) and un-vented Cylinder.
My boiler guy said that the combi was undersized, but it was completely
shot too (you could see the flames through the hole!) - we think it was
a pre-1990 fit.
I suspect a lot of undersized cheap combi's are fitted, and that this
leads to short lives full of breakdown.
I would have gone for another combi (but a much bigger one) but SWMBO
likes the tub too much and in the 35 minutes it took to run one, the
water went cold :-(
An un-vented cylinder (bewa Building Regs) or a HeatStore are a
simpler, but pricey, retrofit than all that header tank gubbins.

R.

On Mon, 16 Oct 2006 20:46:56 +0100, Darran Ames wrote:

Jim D wrote:
Do any of you consider combi boilers and sealed systems a false
economy? I installed my system ten years ago. Since then, I have had
to spend about £100 a year just maintaining the boiler! My boiler
(Chaffateaux Britony 80) has given problems of one sort or another
about once a year, on average, and the parts are not cheap.

snip

I've a 15 year old combi in my house that is ticking along just fine and
hasn't cost me a penny. Touch wood!

What make?... do tell!


--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html
Gas Fitting Standards Docs he http://www.makewrite.demon.co.uk/GasFittingStandards

"Jim D" wrote in message
...

Do any of you consider combi boilers and sealed systems a false
economy? I installed my system ten years ago. Since then, I have had
to spend about £100 a year just maintaining the boiler! My boiler
(Chaffateaux Britony 80) has given problems of one sort or another
about once a year, on average, and the parts are not cheap.

Then there are the other disadvantages associated with combis too..

I'm seriously wondering if I'd save money by ripping the boiler out
and installing a conventional boiler with header tank etc... (It's a
three bed semi).

Or, I could use the combi boiler as a conventional boiler... Would
that be feasable? Then some of the components wouldn't get used (the
diverter valve, the secondary heat exchanger, etc) so they would never
play up!

Best buy a good make of combi instead of bargain basement. Try: Viessmann,
Eco-Hometec, Atmos, Etag.

"Jim" wrote in message
...

harry

Had a back boiler here since 1982 and it has not once given any real
trouble apart from one thermocouple that took 2mins to change. Very
reliable and cheap to run too.
I wouldn't have a combination boiler, no gas fitter I know recommends them
for the very reasons stated. Crap quality, always breaking down and
unreliable.

Then you should go to gas fitters who know what they are talking about.

"Richard Downing" wrote in message
...

An un-vented cylinder (bewa Building Regs) or a HeatStore are a
simpler, but pricey, retrofit than all that header tank gubbins.

Heat stores as you say, which are thermal stores, or heat banks, are about
the same price as unvented cylinders, and less chance of an explosion. Heat
banks generally work on higher pressures.

In message , Jim D
writes

Do any of you consider combi boilers and sealed systems a false
economy?


You bought a Chaff !


--
geoff

In message , Darran
Ames writes
Jim D wrote:
Do any of you consider combi boilers and sealed systems a false
economy? I installed my system ten years ago. Since then, I have had
to spend about £100 a year just maintaining the boiler! My boiler
(Chaffateaux Britony 80) has given problems of one sort or another
about once a year, on average, and the parts are not cheap.

snip

I've a 15 year old combi in my house that is ticking along just fine
and hasn't cost me a penny. Touch wood!

My 18 year old Vaillant needed the fan and the secondary heat exchanger
during it's life

It was still working when it was replaced last year

--
geoff

On 16 Oct 2006 12:17:00 -0700, "Mr Harry" wrote:

what problems have you had so far? are the faults connected, somehow?

Some faults were connected; others weren't:
1) Secondary heat exchanger got clogged with bits of iron oxide.
2) The next one got clogged with limescale (hard water area).
3) Third one went the same way
4) So I installed a phosphate doser.
5) Had to replace CH flow switch,
6) Replaced CH control thermistor,
7) Replaced pressure release valve
8) Expansion vessel failed. Installed stand-alone one.

That's about it over the past 8 or so years. I've certainly spent more
on parts than I spent on the original boiler.

On the other hand, folks seem to have traditional-type boilers that go
year after year with no problems. But that's just my impression.

Jim D

"raden" wrote in message
...
In message , Darran
Ames writes
Jim D wrote:
Do any of you consider combi boilers and sealed systems a false
economy? I installed my system ten years ago. Since then, I have had
to spend about £100 a year just maintaining the boiler! My boiler
(Chaffateaux Britony 80) has given problems of one sort or another
about once a year, on average, and the parts are not cheap.

snip

I've a 15 year old combi in my house that is ticking along just fine and
hasn't cost me a penny. Touch wood!

My 18 year old Vaillant needed the fan and the secondary heat exchanger
during it's life

Maxie that is quite good. The DHW heat exchanger should not have gone at
that age. Was it lime related?

"Jim D" wrote in message
...
On 16 Oct 2006 12:17:00 -0700, "Mr Harry" wrote:

what problems have you had so far? are the faults connected, somehow?

Some faults were connected; others weren't:
1) Secondary heat exchanger got clogged with bits of iron oxide.
2) The next one got clogged with limescale (hard water area).
3) Third one went the same way
4) So I installed a phosphate doser.

The doser probably would have prevented all the above.

5) Had to replace CH flow switch,
6) Replaced CH control thermistor,

They are not big items.

7) Replaced pressure release valve

That should not have gone, but easy to replace.

8) Expansion vessel failed. Installed stand-alone one.

Was there too little or too much inhibitor in the system? Too much and the
rubber diaphragm can perish. You can over-dose.

That's about it over the past 8 or so years. I've certainly spent more
on parts than I spent on the original boiler.

On the other hand, folks seem to have traditional-type boilers that go
year after year with no problems. But that's just my impression.

A combi is a system boiler with an added water section. All is in one case.
A system with separate cylinders may have zone valve and stat failures, yet
these are not regarded as the boiler. All the combis controls are inside
the one case, so anything inside the case is the boiler. Compare like with
like - system vs. system.

Jim D wrote:
Do any of you consider combi boilers and sealed systems a false
economy? I installed my system ten years ago. Since then, I have had
to spend about £100 a year just maintaining the boiler! My boiler
(Chaffateaux Britony 80) has given problems of one sort or another
about once a year, on average, and the parts are not cheap.

Then there are the other disadvantages associated with combis too..

I'm seriously wondering if I'd save money by ripping the boiler out
and installing a conventional boiler with header tank etc... (It's a
three bed semi).

Or, I could use the combi boiler as a conventional boiler... Would
that be feasable? Then some of the components wouldn't get used (the
diverter valve, the secondary heat exchanger, etc) so they would never
play up!

Thanks,

Jim D

Well I shoved in a system (mains pressure) boiler and pressurised tank,
and haven't touched it in 4 years apart from repressurising it once last
winter.

Are you supposed to service these things? ;-)

Jim D wrote:
On 16 Oct 2006 12:17:00 -0700, "Mr Harry" wrote:

what problems have you had so far? are the faults connected, somehow?

Some faults were connected; others weren't:
1) Secondary heat exchanger got clogged with bits of iron oxide.

No secondary heat exchanger on my system boiler.

2) The next one got clogged with limescale (hard water area).
Indirect heating of hot water means scale would be in cylinder anyway,
but I got a softener. So no scale problems anywhere.

3) Third one went the same way
4) So I installed a phosphate doser.

More fool you for not fitting a proper softener from the word go ;-)
5) Had to replace CH flow switch,

Ah. No flow switch on a system boiler.

6) Replaced CH control thermistor,
7) Replaced pressure release valve
8) Expansion vessel failed. Installed stand-alone one.

Mmm. No problems like that on whatever it is I have.

Just had a two way motorized valve stick and screw up the motor.


That's about it over the past 8 or so years. I've certainly spent more
on parts than I spent on the original boiler.

On the other hand, folks seem to have traditional-type boilers that go
year after year with no problems. But that's just my impression.

Jim D

Do any of you consider combi boilers and sealed systems a false
economy?

Actually, sealed systems are easier to maintain than open vented ones, which
are hard to refill, prone to airlocks and hard to debug issues like pumping
over.

As to combis, they aren't that much more complex than many other hot water
systems. Even a vented cylinder has problems such as with corroding coils,
zone valves, limescale and rats in the tank.

Indeed, my heat bank practically contains the water side of a combi boiler,
with flow switches, secondary heat exchangers etc.

However, as to your experiences, you do have a particularly cheap and poorly
regarded make of boiler. When replacing it, choose something decent this
time.

Christian.

"The Natural Philosopher" wrote in message
...
Jim D wrote:
Do any of you consider combi boilers and sealed systems a false
economy? I installed my system ten years ago. Since then, I have had
to spend about £100 a year just maintaining the boiler! My boiler
(Chaffateaux Britony 80) has given problems of one sort or another
about once a year, on average, and the parts are not cheap.

Then there are the other disadvantages associated with combis too..

I'm seriously wondering if I'd save money by ripping the boiler out
and installing a conventional boiler with header tank etc... (It's a
three bed semi).

Or, I could use the combi boiler as a conventional boiler... Would
that be feasable? Then some of the components wouldn't get used (the
diverter valve, the secondary heat exchanger, etc) so they would never
play up!

Thanks,

Jim D

Well I shoved in a system (mains pressure) boiler and pressurised tank,
and haven't touched it in 4 years apart from repressurising it once last
winter.

Are you supposed to service these things? ;-)

Once a year. I would have you locked up.

On Mon, 16 Oct 2006 22:14:06 GMT Raden wrote :
My 18 year old Vaillant needed the fan and the secondary heat exchanger
during it's life

It was still working when it was replaced last year

We had Vaillants in two rented flats and one ran with no problems for 10
years and the other needed one minor repair, £40 or so. I'm hoping that my
Vaillant-inspired Glow-Worm Cxi is no less reliable: coming up 3 years, no
problems so far.

--
Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk

In message ews.net,
Doctor Drivel writes

"raden" wrote in message
...
In message ,
Darran Ames writes
Jim D wrote:
Do any of you consider combi boilers and sealed systems a false
economy? I installed my system ten years ago. Since then, I have had
to spend about £100 a year just maintaining the boiler! My boiler
(Chaffateaux Britony 80) has given problems of one sort or another
about once a year, on average, and the parts are not cheap.

snip

I've a 15 year old combi in my house that is ticking along just fine
and hasn't cost me a penny. Touch wood!

My 18 year old Vaillant needed the fan and the secondary heat
exchanger during it's life

Maxie that is quite good. The DHW heat exchanger should not have gone
at that age. Was it lime related?


Well, it wasn't a lemon ...

boom boom

--
geoff

"raden" wrote in message
...
In message ews.net,
Doctor Drivel writes

"raden" wrote in message
...
In message , Darran
Ames writes
Jim D wrote:
Do any of you consider combi boilers and sealed systems a false
economy? I installed my system ten years ago. Since then, I have had
to spend about £100 a year just maintaining the boiler! My boiler
(Chaffateaux Britony 80) has given problems of one sort or another
about once a year, on average, and the parts are not cheap.

snip

I've a 15 year old combi in my house that is ticking along just fine and
hasn't cost me a penny. Touch wood!

My 18 year old Vaillant needed the fan and the secondary heat exchanger
during it's life

Maxie that is quite good. The DHW heat exchanger should not have gone at
that age. Was it lime related?

Well, it wasn't a lemon ...

boom boom

Oh Maxie you do come out with them. All those funnies and all that.

In article ,
Christian McArdle wrote:
Do any of you consider combi boilers and sealed systems a false
economy?

Actually, sealed systems are easier to maintain than open vented ones,
which are hard to refill, prone to airlocks and hard to debug issues
like pumping over.

A *properly* designed one won't pump over. And how often do you drain and
re-fill a system? And what maintenance is needed on an open system that
isn't needed on others - apart from possibly replacing a ball valve washer
every 25 years?

--
*If at first you don't succeed, redefine success.

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

A *properly* designed one won't pump over.

I rest my case.

Christian.

In article ,
Christian McArdle wrote:
A *properly* designed one won't pump over.

I rest my case.

Why? It's not difficult. There are bound to be problems with poorly
installed pressurized systems too come to that - leaks for one.

--
*A backward poet writes inverse.*

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

A *properly* designed one won't pump over.

I rest my case.

Why? It's not difficult.

Clearly you have greater faith in the majority of people installing these
systems. It is a lot harder to muck up a pressurised system. You are also
much less likely to end up with a dangerous result, although obviously any
system can be dangerous if done too incompetently.

There are bound to be problems with poorly installed pressurized
systems too come to that - leaks for one.

Well leaks are common to all plumbing.

Christian.

In article ,
Christian McArdle wrote:
A *properly* designed one won't pump over.

I rest my case.

Why? It's not difficult.

Clearly you have greater faith in the majority of people installing
these systems.

No - I read some of dribble's postings and realise there are charlatans
around. However, this is DIY and I installed my own. After taking advice.

It is a lot harder to muck up a pressurised system. You
are also much less likely to end up with a dangerous result, although
obviously any system can be dangerous if done too incompetently.

I'm not aware of the 'dangers' of an open system - apart from one
recently reported case, which was down to simple bodging on a number of
fronts including not having obvious faults fixed. But then some
sealed/pressurized systems - if this includes hot water - are known to be
dangerous hence the restrictions on who is allowed to install them and the
periodic safety checks needed.

There are bound to be problems with poorly installed pressurized
systems too come to that - leaks for one.

Well leaks are common to all plumbing.

Again only with poor workmanship.

I realise that sealed systems are the answer to some problems - mainly
space related - but they aren't the panacea some make them out to be.

--
*And don't start a sentence with a conjunction *

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

"Dave Plowman (News)" wrote in message
...
In article ,
Christian McArdle wrote:
A *properly* designed one won't pump over.

I rest my case.

Why? It's not difficult.

Clearly you have greater faith in the majority of people installing
these systems.

However, this is DIY and I installed my own.

Like a pump on one tap. ROFLMAO

After taking advice.

You did? ROFLMAO

Only from the uk.d-i-y Lunatic Association. Yes you read here.

"Christian McArdle" wrote in message
.. .
A *properly* designed one won't pump over.

I rest my case.

Why? It's not difficult.

Clearly you have greater faith in the majority of people installing these
systems. It is a lot harder to muck up a pressurised system. You are also
much less likely to end up with a dangerous result, although obviously any
system can be dangerous if done too incompetently.

There are bound to be problems with poorly installed pressurized
systems too come to that - leaks for one.

Well leaks are common to all plumbing.

Inhibitor is essential to open vented system in many area. Most people do
not re-dose after 4 years.

A sealed system does not necessarily require the stuff, with the vast
majority of systems getting away with it if none is installed. In fact too
much of it, like in one bedroom flats having a full bottle which is good
enough for a 5 bed house, and the expansion vessel diaphragm can perish -
which often does. The inhibitor acts against rubber - an the O rings in the
rad valves..

In article ews.net,
Doctor Drivel wrote:
However, this is DIY and I installed my own.

Like a pump on one tap. ROFLMAO

You can get tablets for that. At your age it can't be good for you.

--
*Time is fun when you're having flies... Kermit

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

On Wed, 18 Oct 2006 10:51:15 +0100, Dave Plowman (News) wrote:

In article ,
Christian McArdle wrote:
A *properly* designed one won't pump over.

I rest my case.

Why? It's not difficult.

Clearly you have greater faith in the majority of people installing
these systems.

No - I read some of dribble's postings and realise there are charlatans
around. However, this is DIY and I installed my own. After taking advice.

It is a lot harder to muck up a pressurised system. You
are also much less likely to end up with a dangerous result, although
obviously any system can be dangerous if done too incompetently.

I'm not aware of the 'dangers' of an open system - apart from one
recently reported case, which was down to simple bodging on a number of
fronts including not having obvious faults fixed. But then some
sealed/pressurized systems - if this includes hot water - are known to be
dangerous hence the restrictions on who is allowed to install them and the
periodic safety checks needed.

There are bound to be problems with poorly installed pressurized
systems too come to that - leaks for one.

Well leaks are common to all plumbing.

Again only with poor workmanship.

I realise that sealed systems are the answer to some problems - mainly
space related - but they aren't the panacea some make them out to be.

I'd say that it's a point win to the sealed circuits. There is little to
choose on reliability stakes between the two arrangements if the
conventional system is correct. I.e the failed expansion vessels probably
balance against the stuck shut float valves, the over flowing header tanks
and the limescale plugs at the entrance to the circuit all of which are
problems that can and do occur on correctly installed conventional systems.

However the the failure modes for incorrect conventional systems are
multiple and severe.


--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html
Gas Fitting Standards Docs he http://www.makewrite.demon.co.uk/GasFittingStandards

"Dave Plowman (News)" wrote in message
...
In article ews.net,
Doctor Drivel wrote:
However, this is DIY and I installed my own.

Like a pump on one tap. ROFLMAO

You can get tablets for that.

Tablets to put on your tap as well. ROFLMAO.