Notwithstanding having a new boiler (W-B 30CDi system boiler) fitted a
couple of months ago, the house is not warm enough and am trying to
understand why. I've just been round the house taking temperatures
using the i/r thermometer I bought with a view to balancing the radiators.

First issue is that the roomstat in the hall is set to 20 deg, yet is
displaying 17 deg (which is approx the actual temp in the hall), and is
calling for heat continually as far as I can see (the boiler seems to
have firing pretty much all day).

I've turned up all the TRVs to maximum today (lockshield valves are set
wherever they have been since installation) and measured flow and return
temps at each radiator and the boiler. With the HW off, boiler flow and
return temps are 63 and 53 Celsius; on the radiators the ranges are
51-63 deg (flow) and 47-57 (return). The temp difference across the rads
ranges from 2.5 to 9.5 deg; most of them are at around 5 deg, which is
much too little, right? (should be about 11 deg?)

I'm puzzled as evidently the overall drop accross the boiler flow and
return is about right, but why is it much too small on *all* the rads?
Where's that heat going?! And how can any fine-tuning of the lockshield
valves sort it out? And/or is the new boiler undersized?

If anyone can suggest what I should be doing to get the house heating
properly I'd be very grateful...

Thanks
David

"Lobster" wrote in message
...
Notwithstanding having a new boiler (W-B 30CDi system boiler) fitted a
couple of months ago, the house is not warm enough and am trying to
understand why. I've just been round the house taking temperatures using
the i/r thermometer I bought with a view to balancing the radiators.

First issue is that the roomstat in the hall is set to 20 deg, yet is
displaying 17 deg (which is approx the actual temp in the hall), and is
calling for heat continually as far as I can see (the boiler seems to
have firing pretty much all day).

I've turned up all the TRVs to maximum today (lockshield valves are set
wherever they have been since installation) and measured flow and return
temps at each radiator and the boiler. With the HW off, boiler flow and
return temps are 63 and 53 Celsius; on the radiators the ranges are 51-63
deg (flow) and 47-57 (return). The temp difference across the rads ranges
from 2.5 to 9.5 deg; most of them are at around 5 deg, which is much too
little, right? (should be about 11 deg?)

I'm puzzled as evidently the overall drop accross the boiler flow and
return is about right, but why is it much too small on *all* the rads?
Where's that heat going?! And how can any fine-tuning of the lockshield
valves sort it out? And/or is the new boiler undersized?

If anyone can suggest what I should be doing to get the house heating
properly I'd be very grateful...

Thanks
David

Have you tried turning up the boiler temperature? If the hall is not getting
up to temperature then either you need a bigger radiator or increase the
system temperature. You may get away with running the boiler at 63C in
spring and autumn but with this cold weather, you may need to increase it. I
have a 24CDI and in winter, the boiler temperature is set at the maximum
(84C).

Archie

On Wed, 30 Dec 2009 23:55:56 +0000, Lobster wrote:

Notwithstanding having a new boiler (W-B 30CDi system boiler) fitted a
couple of months ago, the house is not warm enough and am trying to
understand why. I've just been round the house taking temperatures
using the i/r thermometer I bought with a view to balancing the
radiators.

First issue is that the roomstat in the hall is set to 20 deg, yet is
displaying 17 deg (which is approx the actual temp in the hall), and is
calling for heat continually as far as I can see (the boiler seems to
have firing pretty much all day).

Turn up the boiler output temperature. This needs to be as low as
possible to be efficient, but it may be set too low right now to dump
enough heat into the heating circuit. Turn it down again when the cold
spell is over...experiment!

We have a WB 24Ri and, for only the second time since we've had it, it
was clear last week that the rooms weren't heating properly. Turned it up
a bit, and soon reached desired temperature and the stat finally stopped
demanding heat.



--
Use the BIG mirror service in the UK:
http://www.mirrorservice.org

On Wed, 30 Dec 2009 23:55:56 +0000, Lobster
wrote:

Notwithstanding having a new boiler (W-B 30CDi system boiler) fitted a
couple of months ago, the house is not warm enough and am trying to
understand why. I've just been round the house taking temperatures
using the i/r thermometer I bought with a view to balancing the radiators.

First issue is that the roomstat in the hall is set to 20 deg, yet is
displaying 17 deg (which is approx the actual temp in the hall), and is
calling for heat continually as far as I can see (the boiler seems to
have firing pretty much all day).

I've turned up all the TRVs to maximum today (lockshield valves are set
wherever they have been since installation) and measured flow and return
temps at each radiator and the boiler. With the HW off, boiler flow and
return temps are 63 and 53 Celsius; on the radiators the ranges are
51-63 deg (flow) and 47-57 (return). The temp difference across the rads
ranges from 2.5 to 9.5 deg; most of them are at around 5 deg, which is
much too little, right? (should be about 11 deg?)

I'm puzzled as evidently the overall drop accross the boiler flow and
return is about right, but why is it much too small on *all* the rads?
Where's that heat going?! And how can any fine-tuning of the lockshield
valves sort it out? And/or is the new boiler undersized?

If anyone can suggest what I should be doing to get the house heating
properly I'd be very grateful...

Thanks
David

Your locksheild valves may be all set as almost closed so the water
going in is too low to heat each one up to anything like needed temp
to work.

I have 8 rads but all but 2 are set wide open. The two set lower are
small ones and early in the flow and return, almost like bypass loops.
The system works perfectly.

On Dec 30, 5:55*pm, Lobster wrote:
Notwithstanding having a new boiler (W-B 30CDi system boiler) fitted a
couple of months ago, the house is not warm enough and am trying to
understand why. *I've just *been round the house taking temperatures
using the i/r thermometer I bought with a view to balancing the radiators..

First issue is that the roomstat in the hall is set to 20 deg, yet is
displaying 17 deg (which is approx the actual temp in the hall), and is
calling for heat continually as far as I can see (the boiler seems to
have firing pretty much all day).

I've turned up all the TRVs to maximum today (lockshield valves are set
wherever they have been since installation) and measured flow and return
temps at each radiator and the boiler. *With the HW off, boiler flow and
return temps are 63 and 53 Celsius; on the radiators the ranges are
51-63 deg (flow) and 47-57 (return). The temp difference across the rads
ranges from 2.5 to 9.5 deg; most of them are at around 5 deg, which is
much too little, right? (should be about 11 deg?)

I'm puzzled as evidently the overall drop accross the boiler flow and
return is about right, but why is it much too small on *all* the rads?
Where's that heat going?! *And how can any fine-tuning of the lockshield
valves sort it out? *And/or is the new boiler undersized?

If anyone can suggest what I should be doing to get the house heating
properly I'd be very grateful...

Thanks
David

What is boiler temp, is it cycling fire but pump is running so
thermostat is not satisfied, then turn up boiler water temp. You
manual or the co can tel you what max efficency temp is, but I need it
alot higher when its real cold out, in spring I will lower it

In an earlier contribution to this discussion,
Lobster wrote:

Notwithstanding having a new boiler (W-B 30CDi system boiler) fitted a
couple of months ago, the house is not warm enough and am trying to
understand why. I've just been round the house taking temperatures
using the i/r thermometer I bought with a view to balancing the
radiators.
First issue is that the roomstat in the hall is set to 20 deg, yet is
displaying 17 deg (which is approx the actual temp in the hall), and
is calling for heat continually as far as I can see (the boiler seems
to have firing pretty much all day).

I've turned up all the TRVs to maximum today (lockshield valves are
set wherever they have been since installation) and measured flow and
return temps at each radiator and the boiler. With the HW off,
boiler flow and return temps are 63 and 53 Celsius; on the radiators
the ranges are 51-63 deg (flow) and 47-57 (return). The temp
difference across the rads ranges from 2.5 to 9.5 deg; most of them
are at around 5 deg, which is much too little, right? (should be
about 11 deg?)
I'm puzzled as evidently the overall drop accross the boiler flow and
return is about right, but why is it much too small on *all* the rads?
Where's that heat going?! And how can any fine-tuning of the
lockshield valves sort it out? And/or is the new boiler undersized?

If anyone can suggest what I should be doing to get the house heating
properly I'd be very grateful...

Thanks
David

Let me guess - you simply replaced the boiler and kept the existing
radiators. The house was hot enough with the old boiler - when it worked. Is
that right?

If so, the problem is that your radiators were sized on the assumption that
they would be running at a mean temperature of about 75degC. If you run them
at a mean temperature of less than 60 (as required to get max efficiency out
of a condensing boiler) they'll give out a *lot* less heat. So you either
need bigger radiators to compensate for the lower water temperatures - or
you need to turn the boiler up during periods of very cold weather, and sod
the efficiency.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

On Dec 31, 1:15*am, wrote:
On Wed, 30 Dec 2009 23:55:56 +0000, Lobster





wrote:
Notwithstanding having a new boiler (W-B 30CDi system boiler) fitted a
couple of months ago, the house is not warm enough and am trying to
understand why. *I've just *been round the house taking temperatures
using the i/r thermometer I bought with a view to balancing the radiators.

First issue is that the roomstat in the hall is set to 20 deg, yet is
displaying 17 deg (which is approx the actual temp in the hall), and is
calling for heat continually as far as I can see (the boiler seems to
have firing pretty much all day).

I've turned up all the TRVs to maximum today (lockshield valves are set
wherever they have been since installation) and measured flow and return
temps at each radiator and the boiler. *With the HW off, boiler flow and
return temps are 63 and 53 Celsius; on the radiators the ranges are
51-63 deg (flow) and 47-57 (return). The temp difference across the rads
ranges from 2.5 to 9.5 deg; most of them are at around 5 deg, which is
much too little, right? (should be about 11 deg?)

I'm puzzled as evidently the overall drop accross the boiler flow and
return is about right, but why is it much too small on *all* the rads?
Where's that heat going?! *And how can any fine-tuning of the lockshield
valves sort it out? *And/or is the new boiler undersized?

If anyone can suggest what I should be doing to get the house heating
properly I'd be very grateful...

Thanks
David

Your locksheild valves may be all set as almost closed so the water
going in is too low to heat each one up to anything like needed temp
to work.



But if the flow rate was too small there would be a large tempertaure
drop across each rad. This is not the case apparently.

Robert

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

Notwithstanding having a new boiler (W-B 30CDi system boiler) fitted a
couple of months ago, the house is not warm enough and am trying to
understand why. I've just been round the house taking temperatures
using the i/r thermometer I bought with a view to balancing the
radiators.
First issue is that the roomstat in the hall is set to 20 deg, yet is
displaying 17 deg (which is approx the actual temp in the hall), and
is calling for heat continually as far as I can see (the boiler seems
to have firing pretty much all day).

I've turned up all the TRVs to maximum today (lockshield valves are
set wherever they have been since installation) and measured flow and
return temps at each radiator and the boiler. With the HW off,
boiler flow and return temps are 63 and 53 Celsius; on the radiators
the ranges are 51-63 deg (flow) and 47-57 (return). The temp
difference across the rads ranges from 2.5 to 9.5 deg; most of them
are at around 5 deg, which is much too little, right? (should be
about 11 deg?)
I'm puzzled as evidently the overall drop accross the boiler flow and
return is about right, but why is it much too small on *all* the rads?
Where's that heat going?! And how can any fine-tuning of the
lockshield valves sort it out? And/or is the new boiler undersized?

Let me guess - you simply replaced the boiler and kept the existing
radiators. The house was hot enough with the old boiler - when it worked. Is
that right?

Pretty much. Though the old boiler was also a condensing model, and
about half of the rads predate that installation (2001). It's true that
two of the worst affected rooms have prehistoric rads, so it sounds
worthwhile to change those at least. I don't recall the old boiler
being a problem; although that system didn't have a roomstat but not
sure that's relevant given my symptoms.

If so, the problem is that your radiators were sized on the assumption that
they would be running at a mean temperature of about 75degC. If you run them
at a mean temperature of less than 60 (as required to get max efficiency out
of a condensing boiler) they'll give out a *lot* less heat. So you either
need bigger radiators to compensate for the lower water temperatures - or
you need to turn the boiler up during periods of very cold weather, and sod
the efficiency.

It was certainly particularly cold yesterday - today is fine - so maybe
I do just have to live with cranking up the boiler on such days.

But still not sure why I'm getting the above temperature readings at the
radiators when the flow and return temps at the boiler are 'normal'...
are these observations consistent?

Thanks for all the responses.
David

On Dec 31, 7:33*am, Lobster wrote:
Roger Mills wrote:
In an earlier contribution to this discussion,
Lobster *wrote:

Notwithstanding having a new boiler (W-B 30CDi system boiler) fitted a
couple of months ago, the house is not warm enough and am trying to
understand why. *I've just *been round the house taking temperatures
using the i/r thermometer I bought with a view to balancing the
radiators.
First issue is that the roomstat in the hall is set to 20 deg, yet is
displaying 17 deg (which is approx the actual temp in the hall), and
is calling for heat continually as far as I can see (the boiler seems
to have firing pretty much all day).

I've turned up all the TRVs to maximum today (lockshield valves are
set wherever they have been since installation) and measured flow and
return temps at each radiator and the boiler. *With the HW off,
boiler flow and return temps are 63 and 53 Celsius; on the radiators
the ranges are 51-63 deg (flow) and 47-57 (return). The temp
difference across the rads ranges from 2.5 to 9.5 deg; most of them
are at around 5 deg, which is much too little, right? (should be
about 11 deg?)
I'm puzzled as evidently the overall drop accross the boiler flow and
return is about right, but why is it much too small on *all* the rads?
Where's that heat going?! *And how can any fine-tuning of the
lockshield valves sort it out? *And/or is the new boiler undersized?

Let me guess - you simply replaced the boiler and kept the existing
radiators. The house was hot enough with the old boiler - when it worked. Is
that right?

Pretty much. *Though the old boiler was also a condensing model, and
about half of the rads predate that installation (2001). *It's true that
two of the worst affected rooms have prehistoric rads, so it sounds
worthwhile to change those at least. *I don't recall the old boiler
being a problem; although that system didn't have a roomstat but not
sure that's relevant given my symptoms.

If so, the problem is that your radiators were sized on the assumption that
they would be running at a mean temperature of about 75degC. If you run them
at a mean temperature of less than 60 (as required to get max efficiency out
of a condensing boiler) they'll give out a *lot* less heat. So you either
need bigger radiators to compensate for the lower water temperatures - or
you need to turn the boiler up during periods of very cold weather, and sod
the efficiency.

It was certainly particularly cold yesterday - today is fine - so maybe
I do just have to live with cranking up the boiler on such days.

But still not sure why I'm getting the above temperature readings at the
radiators when the flow and return temps at the boiler are 'normal'...
are these observations consistent?

Thanks for all the responses.
David- Hide quoted text -

- Show quoted text -

Best is to put money in insulation you will not only save on gas usage
but will be able to run at the most efficent boiler temperature.

In message
,
ransley writes
Best is to put money in insulation you will not only save on gas usage
but will be able to run at the most efficent boiler temperature.

All very well if you are happy to put up with a stuffy house.

I'm in the same sort of position as lobster. We had a gas fire with back
boiler in the centre of the house. This was replaced by a similarly
rated condensing boiler situated at the corner of the house in a back
kitchen. One radiator was changed to improve the heating in one room,
otherwise the system was as before.
The supposedly more efficient system is running flat out and all the
rads feel too hot to touch, but only get the lounge up to about 18.5 C
after running all day, so we have to have the gas fire on as well. The
controller is set to 21 and sits calling for heat permanently.

My theory is that the old central boiler "wasted heat" up the centre of
the house so the rads had less work to do. Now we have an inefficient
"efficient" system that will cost us a fortune to run and waste less
heat, but heat the garden.

I must measure all the rad and other temperatures. I have the kit, just
not had the time..
--
Bill

Bill wrote:
In message
,
ransley writes
Best is to put money in insulation you will not only save on gas usage
but will be able to run at the most efficent boiler temperature.

All very well if you are happy to put up with a stuffy house.


Not so. Insulation merely means you can run what ventilation you need,
rather than having to have masses of it to control condensation.

My theory is that the old central boiler "wasted heat" up the centre of
the house so the rads had less work to do. Now we have an inefficient
"efficient" system that will cost us a fortune to run and waste less
heat, but heat the garden.


I think you have it spot on.

We have the same problem. Our "inefficient" back boiler gently heated
the chimney breast in the dining room and upstairs passage, and these
were always comfortable. The dining room fire wasn't used much.

Now with the new efficient boiler we have a cold house and have to use
the fire every time we use the dining room! The other rooms are never
up to temperature and we have to use fires in those as well.

Some efficiency!


Jim

"Lobster" wrote in message
...


If anyone can suggest what I should be doing to get the house heating
properly I'd be very grateful...

The usual problem is the plumber has done the rads too small.
Its the norm as they usually work to an outside temp of 1C and its well
below that ATM.
They never check how well its insulated and just guess
they have no idea how much air is exchanged in the rooms.
This is compounded by the fact that condensing boilers need twice the size
that older non condensing boilers needed if you are going to extract enough
heat.

Turn the boiler temp up to about 75+c and things will be better but it
probably won't be a condensing boiler anymore.

wrote in message
...


Your locksheild valves may be all set as almost closed so the water
going in is too low to heat each one up to anything like needed temp
to work.

You would expect a big temp drop across the rads if that were the case.

"Lobster" wrote in message
...

Pretty much. Though the old boiler was also a condensing model, and about
half of the rads predate that installation (2001). It's true that two of
the worst affected rooms have prehistoric rads, so it sounds worthwhile to
change those at least. I don't recall the old boiler being a problem;
although that system didn't have a roomstat but not sure that's relevant
given my symptoms.

As a short term fix you can blow air across/behind them, this will increase
the heat output from the rad.
I have a small ioniser/filter that I have used on a rad I put in as it is
too small in this weather (but no room for a bigger one).

In message , The Natural Philosopher
writes
Bill wrote:
In message
,
ransley writes
Best is to put money in insulation you will not only save on gas
usage but will be able to run at the most efficent boiler temperature.
All very well if you are happy to put up with a stuffy house.


Not so. Insulation merely means you can run what ventilation you need,
rather than having to have masses of it to control condensation.

But my ongoing point was really that the insulation of the house hasn't
changed, and I like reasonable ventilation. Since the installation of a
more efficient boiler, the house is colder.

We could make a small improvement by increasing insulation, but the
costs would be huge (eg raising a flat roof to put insulation beneath
it) and, where we have a loft, the huge piles of books are probably more
efficient than lifting the boards and adding layers of fibreglass.

I'm afraid that I feel that in most areas we are becoming marshalled
into mental straitjackets rather than encouraged to apply logical
intelligent thought. Almost every area I've been forced into recently
seems to have involved needless reduction in my living standards. The
central heating gives less heat, light bulbs give less light, fence
treatment appears to be turning from oil-based that works to water based
that falls off and don't start me about modern cars after my recent
experiences with main dealers proudly boasting about an 18 month old car
that "it has a new flywheel" (another story too long for here)..

Maybe it's true - I have lived too long.
--
Bill

On Dec 31, 9:40*pm, Bill wrote:
modern cars after my recent experiences with main
dealers proudly boasting about an 18 month old car
that "it has a new flywheel" (another story too long for here).

Dual Mass?
They cost quite a lot more than the old type if they fail :-)

On Thu, 31 Dec 2009 15:55:48 -0800 (PST), "js.b1"
wrote:

On Dec 31, 9:40*pm, Bill wrote:
modern cars after my recent experiences with main
dealers proudly boasting about an 18 month old car
that "it has a new flywheel" (another story too long for here).

Dual Mass?
They cost quite a lot more than the old type if they fail :-)


I've had my dual mass flywheel "repaired" under warranty four times in
the last eight months. I say "repaired" because it needs doing again,
and there are only four months left on the warranty.

On Jan 1, 12:11*am, Bruce wrote:
I've had my dual mass flywheel "repaired" under warranty four times in
the last eight months. *I say "repaired" because it needs doing again,
and there are only four months left on the warranty.

Go to www.honestjohn.co.uk and select Technical and your marque/model
of car.

There may be a recall, design fault etc and a known fix.
There used to be just 2 makers of DMF (Dual Mass Flywheel) and one
used by major car brands was known to be problematic except for useful
dealer 100% markup remuneration. The other DMF brand was known to be
superior and not subject to the same problem.

DMF are used particularly with turbo diesel engine cars. Higher torque
engines invariably require straight-cut gear-teeth to achieve the
necessary strength, limit excessive thrust forces, achieve lightness &
avoid expensive through hardening processes. Straight-cut gear-teeth
have the downside that at traffic light idle they would sound
literally like a very large articulated lorry gearbox idle rattle -
basically the teeth hunt up & down in rpm and rattling accordingly.
For dual camshafts this problem is usually resolved by tensioning
springs (friction springs or extra intermeshing gears with odd numbers
of teeth to those on the main shaft), but it is impractical on a
transmission. Instead a much bigger "tensioning spring" sized at the
flywheel is used, a DMF, which counteract the rattle. The rattle can
actually cause microshock loads which affects hardening over time, it
is not entirely aesthetic.

The problem is the DMF technology is relatively new and they are
expensive - worse some marque uses their own designs or modify
existing designs, not always successfully since there is a degree of
"R&D" about it. The camshaft systems required quite a lot of trial and
error w.r.t. temperature, oil viscosity and so on as the load varied
for example.

Much of recent cars is "expensive", "new", "unproven" and your bank
balance funds the R&D, er, I mean maintenance. Worse, Gordon Brown has
no UK car industry to protect so that will become his new target under
"green".

"Jim Lacey" wrote in message
...


My theory is that the old central boiler "wasted heat" up the centre of
the house so the rads had less work to do. Now we have an inefficient
"efficient" system that will cost us a fortune to run and waste less
heat, but heat the garden.


I think you have it spot on.

We have the same problem. Our "inefficient" back boiler gently heated
the chimney breast in the dining room and upstairs passage, and these
were always comfortable. The dining room fire wasn't used much.

Now with the new efficient boiler we have a cold house and have to use
the fire every time we use the dining room! The other rooms are never
up to temperature and we have to use fires in those as well.

Some efficiency!


Jim

I don't think you can beat decent gas fires. They look warm, they heat the
room, you can stand in front of them and warm yourself, you can keep the
tea-pot/food warm on some of them. You expect heat from the fire-place, it's
a focal point and you arrange furniture to suit, cosy. 8 of our 10 ch rads
are now turned off, far too expensive to run and they simply don't radiate
or convect like a decent gas fire. So for us, it's gas fires (in rooms we
occupy), leccy fan heaters in loos (when occupied) and leccy blankets in
bedrooms (fresher & less stuffy). We're actually using antique 'crystalglow'
fires, beats the crap out of the 'living flame' crud.

Jim Lacey wrote:
My theory is that the old central boiler "wasted heat" up the centre of
the house so the rads had less work to do. Now we have an inefficient
"efficient" system that will cost us a fortune to run and waste less
heat, but heat the garden.


I think you have it spot on.

We have the same problem. Our "inefficient" back boiler gently heated
the chimney breast in the dining room and upstairs passage, and these
were always comfortable. The dining room fire wasn't used much.

Now with the new efficient boiler we have a cold house and have to use
the fire every time we use the dining room! The other rooms are never
up to temperature and we have to use fires in those as well.

Some efficiency!


we find the same with the aga. Heats half a pretty large house. Once the
actual CH comes in, its bloody cold already and it REALLY chews oil.



Jim

"Bruce" wrote in message
...
On Thu, 31 Dec 2009 15:55:48 -0800 (PST), "js.b1"
wrote:

On Dec 31, 9:40 pm, Bill wrote:
modern cars after my recent experiences with main
dealers proudly boasting about an 18 month old car
that "it has a new flywheel" (another story too long for here).

Dual Mass?
They cost quite a lot more than the old type if they fail :-)


I've had my dual mass flywheel "repaired" under warranty four times in
the last eight months. I say "repaired" because it needs doing again,
and there are only four months left on the warranty.


A conventional flywheel would outlive a car without ever needing any
consideraration - however DMF along with many other improvements have made a
significant contribution to reliable and economical motoring (I recall
taking my greasegun with me on holidays as the steering on my first car used
to get a bit heavy after a few hundred miles). similar - modern ignition
systems don't suffer the niggling problems in damp weather. Many other
examples could be offered and occasionally sods law strikes and an
improvement leads to you having to repair something that at one time didn't
exist - but consider it holistically.

On Thu, 31 Dec 2009 16:58:50 -0800 (PST), "js.b1"
wrote:

On Jan 1, 12:11*am, Bruce wrote:
I've had my dual mass flywheel "repaired" under warranty four times in
the last eight months. *I say "repaired" because it needs doing again,
and there are only four months left on the warranty.

Go to www.honestjohn.co.uk and select Technical and your marque/model
of car.

There may be a recall, design fault etc and a known fix.
There used to be just 2 makers of DMF (Dual Mass Flywheel) and one
used by major car brands was known to be problematic except for useful
dealer 100% markup remuneration. The other DMF brand was known to be
superior and not subject to the same problem.

DMF are used particularly with turbo diesel engine cars. Higher torque
engines invariably require straight-cut gear-teeth to achieve the
necessary strength, limit excessive thrust forces, achieve lightness &
avoid expensive through hardening processes. Straight-cut gear-teeth
have the downside that at traffic light idle they would sound
literally like a very large articulated lorry gearbox idle rattle -
basically the teeth hunt up & down in rpm and rattling accordingly.
For dual camshafts this problem is usually resolved by tensioning
springs (friction springs or extra intermeshing gears with odd numbers
of teeth to those on the main shaft), but it is impractical on a
transmission. Instead a much bigger "tensioning spring" sized at the
flywheel is used, a DMF, which counteract the rattle. The rattle can
actually cause microshock loads which affects hardening over time, it
is not entirely aesthetic.

The problem is the DMF technology is relatively new and they are
expensive - worse some marque uses their own designs or modify
existing designs, not always successfully since there is a degree of
"R&D" about it. The camshaft systems required quite a lot of trial and
error w.r.t. temperature, oil viscosity and so on as the load varied
for example.

Much of recent cars is "expensive", "new", "unproven" and your bank
balance funds the R&D, er, I mean maintenance. Worse, Gordon Brown has
no UK car industry to protect so that will become his new target under
"green".


Thanks very much for the time you took to reply. I really appreciate
it. The Honest John site came up trumps - it identifies a DMF/clutch
problem suggesting that my car if used for multiple short journeys can
suffer either DMF or clutch failure at intervals as low as 40,000
miles. The car does 25-27,000 miles a year with many short journeys
interspersed between longer journeys, so there is clearly a risk that
these problems will continue and could cost a lot of money when the
car is outside warranty.

I can extend the warranty for a further year from April 2010 for a
reasonable sum, so I will do that. If the problems continue into 2010
I will sell the car and buy a replacement. To be honest, I really
wanted an automatic but bought this manual car because the franchised
dealer was closing down and I got an excellent deal for cash. The
car is very suitable for my needs and is otherwise excellent in every
respect, so an automatic version would appear to be the answer.

On Fri, 1 Jan 2010 10:24:41 -0000, "John"
wrote:


"Bruce" wrote in message
.. .
On Thu, 31 Dec 2009 15:55:48 -0800 (PST), "js.b1"
wrote:

On Dec 31, 9:40 pm, Bill wrote:
modern cars after my recent experiences with main
dealers proudly boasting about an 18 month old car
that "it has a new flywheel" (another story too long for here).

Dual Mass?
They cost quite a lot more than the old type if they fail :-)


I've had my dual mass flywheel "repaired" under warranty four times in
the last eight months. I say "repaired" because it needs doing again,
and there are only four months left on the warranty.


A conventional flywheel would outlive a car without ever needing any
consideraration - however DMF along with many other improvements have made a
significant contribution to reliable and economical motoring (I recall
taking my greasegun with me on holidays as the steering on my first car used
to get a bit heavy after a few hundred miles). similar - modern ignition
systems don't suffer the niggling problems in damp weather. Many other
examples could be offered and occasionally sods law strikes and an
improvement leads to you having to repair something that at one time didn't
exist - but consider it holistically.


You make a good point about modern cars being generally more reliable.
Generally, I agree, but the DMF has made no contribution to this
increase in reliability.

There are several unrelated brands of car that use dual mass flywheels
and they all seem to exhibit weaknesses that make a complete nonsense
of any claims to greater reliability.

For an extremely clear and concise explanation of the particular
problems with DMFs please read js.b1's reply to my previous post.

js.b1 wrote:

DMF are used particularly with turbo diesel engine cars. Higher torque
engines invariably require straight-cut gear-teeth to achieve the
necessary strength, limit excessive thrust forces, achieve lightness &
avoid expensive through hardening processes. Straight-cut gear-teeth
have the downside that at traffic light idle they would sound
literally like a very large articulated lorry gearbox idle rattle -
basically the teeth hunt up & down in rpm and rattling accordingly.

All of this mystifies me. AFAIK no ordinary road cars have straight cut
gearboxes, or if there are any it's very few ultra high performance oriented
ones. Straight cut gears make noise under heavy load, basically a god awful
howling, as anyone who's been involved with race cars know, and nothing you
could do to eliminate noise at idle, even if they do make an unusual amount
of noise at idle which I don't even think is the case, would affect this in
any way.


For dual camshafts this problem is usually resolved by tensioning
springs (friction springs or extra intermeshing gears with odd numbers
of teeth to those on the main shaft), but it is impractical on a
transmission. Instead a much bigger "tensioning spring" sized at the
flywheel is used, a DMF, which counteract the rattle. The rattle can
actually cause microshock loads which affects hardening over time, it
is not entirely aesthetic.

Again, camshafts, especially dual OHC camshafts in modern engines, are
either driven by belt in nearly every case or occasionally by chain.
Straight cut gear teeth do not even factor into this part of the engine.

DMFs are used to reduce transmission rattle by cushioning torsional input
loads from the engine. They also have somewhat of a mitigating effect on
driveline clonk caused by shock loadings from rapid power applications or
gear changes. IMO a sledgehammer, and a very unreliable and expensive one at
that, to crack a pretty non-existant nut.

I wouldn't buy a car with a DMF if you paid me, especially one that already
had a decent mileage on it. I'd rather have a car with a miniscule bit of
rattling you'd never hear with the radio on anyway than one which requires
£1500 to be spent on it every couple of years. In fact my petrol Focus
actually has a slight gearbox noise at very low speed but it was several
years before I even noticed it until that one day I was crawling down a
country lane with the window open and the radio off. Up till then Capital
radio or the CD player had entirely masked it. Why anyone would even worry
about such a slight inconvenience is beyond me. Failed DMFs just make a ****
load of money for car manufacturers is all I can assume and only buyers
refusing to countenance them will see the demise of the damn things.
--
Dave Baker
Puma Race Engines

In message , John
writes

"Bruce" wrote in message
.. .
On Thu, 31 Dec 2009 15:55:48 -0800 (PST), "js.b1"
wrote:

On Dec 31, 9:40 pm, Bill wrote:
modern cars after my recent experiences with main
dealers proudly boasting about an 18 month old car
that "it has a new flywheel" (another story too long for here).

Dual Mass?
They cost quite a lot more than the old type if they fail :-)


I've had my dual mass flywheel "repaired" under warranty four times in
the last eight months. I say "repaired" because it needs doing again,
and there are only four months left on the warranty.


A conventional flywheel would outlive a car without ever needing any
consideraration - however DMF along with many other improvements have made a
significant contribution to reliable and economical motoring (I recall
taking my greasegun with me on holidays as the steering on my first car used
to get a bit heavy after a few hundred miles). similar - modern ignition
systems don't suffer the niggling problems in damp weather. Many other
examples could be offered and occasionally sods law strikes and an
improvement leads to you having to repair something that at one time didn't
exist - but consider it holistically.


This has gone way OT, but still......
My first car, a Ford Prefect took me all over the country. Only the
abysmal maintenance by the main Ford agent in Cardiff defeated me and
it.
Then a succession of Mk1 Cortinas were cheerful, cheap to run and I
carried 8x4 sheets of ply in the estate. That one, the 1.5 estate is
what I wish I could buy today but possibly with a simple diesel engine.
A Princess (impossible to maintain) and Montego (rustbucket) were
OK'ish, then 3 Omega estates, no rust and take the 8x4 ply. Ist 2 were
great, 3rd utterly ludicrous overcomplication and horrendous repair
costs only did 95k miles rather than the 200k I expected and got
previously.

I have a grease gun for the lathe and for when I had Defenders, but
never needed to carry one on the road.

Last month's experience with a Focus estate advertised by main dealer
was..... Called in, car up on hoist having DM flywheel replaced under
remaining Ford warranty. No other Focus estate there, so couldn't test
to see if rear seat space acceptable. Inspected underneath only. Week
passed. Car down and ready. Sat in front and back, think it's smaller in
back than hatch, so prob unsuitable. Commented on smell of diesel.
Dealer said just been worked on, so expected. Test drive fine, felt
nice, commented on trip meter saying 7mpg. Dealer said just been worked
on needs reset. Parked, in old trousers, so knelt down looked under car
diesel dripping. Dealer, nice suit, went to find mechanic. Mechanic said
Yes those pipes fell off in workshop we pushed them back on, probably
have to order new push on plastic pipes I made holistic decision and
walked.
I've now bought something else. It judders at certain rpm in all gears
under load. Must have missed that rpm on test drive. Is it the flywheel?
Back in next week for them to say.

I've posted this sort of thing here there and everywhere. I want a car
with a proper spare wheel, of sensible size to carry junk and a limited
mobility back seat passenger, that runs on diesel and is not a target
for political parasites to plunder for car tax. I want reliability and
simplicity.

I wanted my central heating central.

Why does "efficient" have to work against this and common sense?

--
Bill

Dave Baker wrote:
js.b1 wrote:

DMF are used particularly with turbo diesel engine cars. Higher torque
engines invariably require straight-cut gear-teeth to achieve the
necessary strength, limit excessive thrust forces, achieve lightness &
avoid expensive through hardening processes. Straight-cut gear-teeth
have the downside that at traffic light idle they would sound
literally like a very large articulated lorry gearbox idle rattle -
basically the teeth hunt up & down in rpm and rattling accordingly.

All of this mystifies me. AFAIK no ordinary road cars have straight cut
gearboxes, or if there are any it's very few ultra high performance oriented
ones. Straight cut gears make noise under heavy load, basically a god awful
howling, as anyone who's been involved with race cars know, and nothing you
could do to eliminate noise at idle, even if they do make an unusual amount
of noise at idle which I don't even think is the case, would affect this in
any way.


Never ever seen a straight cut road box in the last 50 years..maybe
reverse gear in a 1948 ford pop..

For dual camshafts this problem is usually resolved by tensioning
springs (friction springs or extra intermeshing gears with odd numbers
of teeth to those on the main shaft), but it is impractical on a
transmission. Instead a much bigger "tensioning spring" sized at the
flywheel is used, a DMF, which counteract the rattle. The rattle can
actually cause microshock loads which affects hardening over time, it
is not entirely aesthetic.

Again, camshafts, especially dual OHC camshafts in modern engines, are
either driven by belt in nearly every case or occasionally by chain.
Straight cut gear teeth do not even factor into this part of the engine.


IIRC one or two were done with gears..but I cant recall exactly which,
so I could be wrong.

DMFs are used to reduce transmission rattle by cushioning torsional input
loads from the engine. They also have somewhat of a mitigating effect on
driveline clonk caused by shock loadings from rapid power applications or
gear changes. IMO a sledgehammer, and a very unreliable and expensive one at
that, to crack a pretty non-existant nut.

I think I have to agree 100%.


I wouldn't buy a car with a DMF if you paid me, especially one that already
had a decent mileage on it. I'd rather have a car with a miniscule bit of
rattling you'd never hear with the radio on anyway than one which requires
£1500 to be spent on it every couple of years. In fact my petrol Focus
actually has a slight gearbox noise at very low speed but it was several
years before I even noticed it until that one day I was crawling down a
country lane with the window open and the radio off. Up till then Capital
radio or the CD player had entirely masked it. Why anyone would even worry
about such a slight inconvenience is beyond me. Failed DMFs just make a ****
load of money for car manufacturers is all I can assume and only buyers
refusing to countenance them will see the demise of the damn things.

After all, a clutch with springs in it is anyway pretty much a DMF,
except the second part of the mass is the gearbox input shaft assembly.

I suspect Ford was trying to reduce total flywheel mass. And still not
have a clunky car.

Well that's Ford for you.

Bill wrote:

I've posted this sort of thing here there and everywhere. I want a car
with a proper spare wheel, of sensible size to carry junk and a limited
mobility back seat passenger, that runs on diesel and is not a target
for political parasites to plunder for car tax. I want reliability and
simplicity.


Skoda. Dirt cheap second hand, because they still carry a totally
unwarranted (sic!) stigma.


I wanted my central heating central.

Why does "efficient" have to work against this and common sense?


Bad is the new good.

read the hilarious novel 'Incompetnce' by Rob Grant, ISBN 978-0-575-07499-1

In the context of building regs, the requirements for insulation and
airtightness are totally destroyed by the requirements for adequate
ventilation.

Unless you use heat recovery ventilation this sets an upper limit on the
amount of insulation its worth putting in a house.

If you want to use a heatpump, or low output temp 'efficient' boiler,
you need to double up on your radiator sizings as well.

Or face using your efficient boiler in a more inefficient part of its
curve.

None of this is headline news, because after all, the whole point of an
'eco' technology, is not to present a low carbon efficient way to do
what's needed, but to make you feel less guilty after shelling out four
times what its worth to acquire it.

On Fri, 01 Jan 2010 15:25:31 +0000, The Natural Philosopher wrote:

Never ever seen a straight cut road box in the last 50 years..maybe
reverse gear in a 1948 ford pop..

My 2.2 litre Humber Hawk (nearly 50 years!) had a straight cut box. I had
to dismantle it to change first gear and the layshaft...

--
Use the BIG mirror service in the UK:
http://www.mirrorservice.org

The Natural Philosopher wrote:

Never ever seen a straight cut road box in the last 50 years..maybe
reverse gear in a 1948 ford pop..

Umm not looked at a Mini then?

In message , The Natural Philosopher
writes
Bill wrote:

I've posted this sort of thing here there and everywhere. I want a
car with a proper spare wheel, of sensible size to carry junk and a
limited mobility back seat passenger, that runs on diesel and is not a
target for political parasites to plunder for car tax. I want
reliability and simplicity.


Skoda. Dirt cheap second hand, because they still carry a totally
unwarranted (sic!) stigma.

Hmm, the thing I have bought is an Octavia estate and it judders at
1500rpm.
18k miles, 2 years warranty and I hope to confirm next week that the
dealer's locally good reputation is justified. I also haven't yet
confirmed what I have seen on the 'net which is that a single mass
flywheel is an official replacement option.

Of course, it might not be the flywheel, but I can't think of many other
parts that would give the symptoms.
--
Bill

Bob Eager wrote:
On Fri, 01 Jan 2010 15:25:31 +0000, The Natural Philosopher wrote:

Never ever seen a straight cut road box in the last 50 years..maybe
reverse gear in a 1948 ford pop..

My 2.2 litre Humber Hawk (nearly 50 years!) had a straight cut box. I had
to dismantle it to change first gear and the layshaft...

that sounds about right..great car that!

straight cut boxes and side valve (car) engines petered out in the 60's.
My guess is the gear cutting machines were simply better, and helical
gears sounded better and were not unduly expensive to make. You did need
good thrust bearings in the box tho. or double helical gears..and that's
really when synchromesh was the rule, not the exception, on ALL gears.,
even first!!



and it was all mainly 2:1 chain off the crank to the camshaft, and a
distributor spiral geared off that, or in the case of OHC, run directly
off the shaft end.

Belts came a lot later. Once materials that could handle the strain were
available..fiber glass and kevlar I suspect.

Steve Firth wrote:
The Natural Philosopher wrote:

Never ever seen a straight cut road box in the last 50 years..maybe
reverse gear in a 1948 ford pop..

Umm not looked at a Mini then?

those aren't straight cut. First and reverse might have been.

On Fri, 01 Jan 2010 17:13:36 +0000, The Natural Philosopher wrote:

Bob Eager wrote:
On Fri, 01 Jan 2010 15:25:31 +0000, The Natural Philosopher wrote:

Never ever seen a straight cut road box in the last 50 years..maybe
reverse gear in a 1948 ford pop..

My 2.2 litre Humber Hawk (nearly 50 years!) had a straight cut box. I
had to dismantle it to change first gear and the layshaft...

that sounds about right..great car that!

straight cut boxes and side valve (car) engines petered out in the 60's.
My guess is the gear cutting machines were simply better, and helical
gears sounded better and were not unduly expensive to make. You did need
good thrust bearings in the box tho. or double helical gears..and that's
really when synchromesh was the rule, not the exception, on ALL gears.,
even first!!

I did have a car with a gear-driven camshaft...but a lot earlier. 1952
Land Rover...side valve, pushrods, low slung camshaft. And no synchromesh
on first or second. That's when I learned to double declutch (not that I
owned the car until 1972).
--
Use the BIG mirror service in the UK:
http://www.mirrorservice.org

The Natural Philosopher wrote:

Steve Firth wrote:
The Natural Philosopher wrote:

Never ever seen a straight cut road box in the last 50 years..maybe
reverse gear in a 1948 ford pop..

Umm not looked at a Mini then?

those aren't straight cut.

It depends on which part of the geartrain one is talking abut.

First and reverse might have been.

And the final drive was for an awful long time. Hence the racket the
gearbox made.

Bill wrote:
In message , The Natural Philosopher
writes
Bill wrote:

I've posted this sort of thing here there and everywhere. I want a
car with a proper spare wheel, of sensible size to carry junk and a
limited mobility back seat passenger, that runs on diesel and is not
a target for political parasites to plunder for car tax. I want
reliability and simplicity.


Skoda. Dirt cheap second hand, because they still carry a totally
unwarranted (sic!) stigma.

Hmm, the thing I have bought is an Octavia estate and it judders at
1500rpm.
18k miles, 2 years warranty and I hope to confirm next week that the
dealer's locally good reputation is justified. I also haven't yet
confirmed what I have seen on the 'net which is that a single mass
flywheel is an official replacement option.


Of course, it might not be the flywheel, but I can't think of many other
parts that would give the symptoms.

Oh, 18k miles, it isn't run in yet. My defender did that at 3000 RPM
until about 45k miles.

On Fri, 01 Jan 2010 15:35:05 +0000, The Natural Philosopher wrote:
Bill wrote:

I've posted this sort of thing here there and everywhere. I want a car
with a proper spare wheel, of sensible size to carry junk and a limited
mobility back seat passenger, that runs on diesel and is not a target
for political parasites to plunder for car tax. I want reliability and
simplicity.


Skoda. Dirt cheap second hand, because they still carry a totally
unwarranted (sic!) stigma.


I wanted my central heating central.

Why does "efficient" have to work against this and common sense?


Bad is the new good.

read the hilarious novel 'Incompetnce' by Rob Grant, ISBN 978-0-575-07499-1

Don't you mean "Incompetnece"? or was that irony on your part :-)
I've read the book - laughed a lot. I also predict, sadly, that it'll
be the "1984" for the 21st century.

On Fri, 01 Jan 2010 15:35:05 +0000, The Natural Philosopher
wrote:
Bill wrote:

I've posted this sort of thing here there and everywhere. I want a car
with a proper spare wheel, of sensible size to carry junk and a limited
mobility back seat passenger, that runs on diesel and is not a target
for political parasites to plunder for car tax. I want reliability and
simplicity.


Skoda. Dirt cheap second hand, because they still carry a totally
unwarranted (sic!) stigma.


Skoda eh?

The car I am having serious DMF problems with (see above) is a Skoda
Octavia. It is my second Octavia.

I put 154,000 miles on the first one and the only serious problem I
had with it was when a drive belt broke at 144,000. The flailing belt
did a lot of damage but until then the car had required only routine
servicing. After repair I sold the car to a local taxi firm and last
time I saw it the odometer was reading 218,000.

But the new Octavia with dual mass flywheel is an altogether different
proposition.

It isn't only the dual mass flywheel. A work colleague runs an
Octavia with the same engine as mine (2.0 litre PD TDi 140 bhp) but
with the DSG gearbox (paddle shift hear change) which is a quite
different design. Mine is a conventional six speed.

After 106,000 miles he is on his third gearbox and now, just out of
warranty, it is exhibiting the same fault once again. The estimate
for a new gearbox, fitted, is just under £4000 but he has been offered
a goodwill payment of £1300 towards the cost.

We are both now considering conventional automatics. Neither car has
had any problems apart from those with the gearbox, and the
conventional auto has a good reputation for reliability.

I haven't lost faith in the brand as a whole but I would advise people
to steer clear of dual mass flywheels and DSG gearboxes, both of which
have had problems in VW, Audi, SEAT and Skoda models.

On Fri, 1 Jan 2010 17:12:55 +0000, Bill wrote:

In message , The Natural Philosopher
writes
Bill wrote:

I've posted this sort of thing here there and everywhere. I want a
car with a proper spare wheel, of sensible size to carry junk and a
limited mobility back seat passenger, that runs on diesel and is not a
target for political parasites to plunder for car tax. I want
reliability and simplicity.


Skoda. Dirt cheap second hand, because they still carry a totally
unwarranted (sic!) stigma.

Hmm, the thing I have bought is an Octavia estate and it judders at
1500rpm.
18k miles, 2 years warranty and I hope to confirm next week that the
dealer's locally good reputation is justified. I also haven't yet
confirmed what I have seen on the 'net which is that a single mass
flywheel is an official replacement option.

Of course, it might not be the flywheel, but I can't think of many other
parts that would give the symptoms.


If the judder is at exactly the same RPM in all gears, it will almost
certainly be either the engine mountings or the exhaust system.

In message , Bruce
writes
We are both now considering conventional automatics. Neither car has
had any problems apart from those with the gearbox, and the
conventional auto has a good reputation for reliability.

And I wish I could have found a conventional diesel automatic at a price
I could afford and that was new enough to satisfy SWMBO.

I've had conventional automatics for ages and have had no transmission
problems ever. My Disco diesel automatic is fine even with quite a bit
of low-range towing of heavy boats around a field, and son's '97 Merc
diesel auto that I found for him locally is excellent. In the real
world, the small consumption hit is negligible compared with the
advantages.
--
Bill