Given the current weather, anyone any ideas what causes problems with
condensing boilers when it isn't the condensate pipe? CAn flue pipes
themselves freeze?

I have a 3-month old Worcester Greenstar CDi COnventional, 30 IIRC. It
is mounted in the cellar, with the tope just below external ground
level. The Flue apparently does a dog-leg within the thick stone walls,
then exits about 12" above ground level, then has an extension kit to
raise the (often dramatic) pluming above window level. The condensate
pipe runs internally under the flooring, and empties into the drainage
sump. I've double checked, this pipe is clear and free-flowing.

Everything has apparently been fine til today, we had hot water and
radiators the morning. May or may not be relevant that this is the first
day for a fortnight where daytime temperatures here have struggled to
marginally above freezing. At lunchtime, I noticed that the light on the
boiler was flashing, and the display gave an error code "EA", which
appears to be about as specific as the average Microsoft error code. I
pressed the reset button, and it appeared to fire up, but only for 20
seconds or so, then I noticed water dripping from under the boiler.
Closer inspection revealed quite a lot of water behind the panelling,
suggesting it had been leaking for several hours at least, or
intermittently for longer. Switched it all off and took out the fuse.

Inside, there is water lying on a ledge above the level of the sump/
condensate apparatus, but no obvious source.

Outside, the flue did not appear to be frozen - there were some water
drops on the lower pipe, and it all sounded perfectly hollow. To be
sure, I poured a large jug of fairly hot water over it, back inside,
more water then appeared inside the boiler apparently from somewhere
around the flue exit, so presumably either from what I had poured on or
possibly from something melting internally.

I'm reluctant to turn it back on with the free water, currently have a
fan heater on it before I risk any electrical connection again.

We have had reported temperatures as low as -10C in this area in the
last couple of nights, so it is perfectly possible for unusual things to
have frozen, but I would have expected it not to have worked first thing.

Any ideas, do flue pipes freeze?

For the comfort and convenience of the locals, I have posted this
separately to The Shed, rather than simply cross-posting!

Cheers folks.

--
JonG
.... the hydrostatic paradox of controversy. Don't you know what that
means? Well, I will tell you. You know that, if you had a bent tube,
one arm of which was of the size of a pipe-stem, and the other big
enough to hold the ocean, water would stand at the same height in
one as in the other. Controversy equalizes fools and wise men in
the same way. And the fools know it. Oliver Wendell Holmes

"JonG" wrote in message
...
#

Any ideas, do flue pipes freeze?

When it was actually very cold in about 1982 enough ice and snow and frozen
flu gases collected on some of the neighbours balanced flues to stop them
working. They had to chip the ice off a couple of times a day, usually at
night.

"JonG" wrote in message
...

Given the current weather, anyone any ideas what causes problems with
condensing boilers when it isn't the condensate pipe? CAn flue pipes
themselves freeze?

I have a 3-month old Worcester Greenstar CDi COnventional, 30 IIRC. It is
mounted in the cellar, with the tope just below external ground level. The
Flue apparently does a dog-leg within the thick stone walls, then exits
about 12" above ground level, then has an extension kit to raise the
(often dramatic) pluming above window level. The condensate pipe runs
internally under the flooring, and empties into the drainage sump. I've
double checked, this pipe is clear and free-flowing.

Everything has apparently been fine til today, we had hot water and
radiators the morning. May or may not be relevant that this is the first
day for a fortnight where daytime temperatures here have struggled to
marginally above freezing. At lunchtime, I noticed that the light on the
boiler was flashing, and the display gave an error code "EA", which
appears to be about as specific as the average Microsoft error code. I
pressed the reset button, and it appeared to fire up, but only for 20
seconds or so, then I noticed water dripping from under the boiler. Closer
inspection revealed quite a lot of water behind the panelling, suggesting
it had been leaking for several hours at least, or intermittently for
longer. Switched it all off and took out the fuse.

Inside, there is water lying on a ledge above the level of the sump/
condensate apparatus, but no obvious source.

Outside, the flue did not appear to be frozen - there were some water
drops on the lower pipe, and it all sounded perfectly hollow. To be sure,
I poured a large jug of fairly hot water over it, back inside, more water
then appeared inside the boiler apparently from somewhere around the flue
exit, so presumably either from what I had poured on or possibly from
something melting internally.

I'm reluctant to turn it back on with the free water, currently have a fan
heater on it before I risk any electrical connection again.

We have had reported temperatures as low as -10C in this area in the last
couple of nights, so it is perfectly possible for unusual things to have
frozen, but I would have expected it not to have worked first thing.

Any ideas, do flue pipes freeze?

For the comfort and convenience of the locals, I have posted this
separately to The Shed, rather than simply cross-posting!

Cheers folks.

Check the condensate path is not blocked, it appears to be.

JonG wrote:

Given the current weather, anyone any ideas what causes problems with
condensing boilers when it isn't the condensate pipe? CAn flue pipes
themselves freeze?

I have a 3-month old Worcester Greenstar CDi COnventional,

....
Everything has apparently been fine til today, we had hot water and
radiators the morning. May or may not be relevant that this is the first
day for a fortnight where daytime temperatures here have struggled to
marginally above freezing.

....

Outside, the flue did not appear to be frozen - there were some water
drops on the lower pipe, and it all sounded perfectly hollow. To be
sure, I poured a large jug of fairly hot water over it, back inside,
more water then appeared inside the boiler apparently from somewhere
around the flue exit, so presumably either from what I had poured on or
possibly from something melting internally.

Further thought is that the water I poured over it was finding its way
in via the inlet part of the balanced flue, which would suggest that the
initial water was mel****er and the warmer (or, at least, less extreme)
temperature Is relevant.

--
JonG
.... the hydrostatic paradox of controversy. Don't you know what that
means? Well, I will tell you. You know that, if you had a bent tube,
one arm of which was of the size of a pipe-stem, and the other big
enough to hold the ocean, water would stand at the same height in
one as in the other. Controversy equalizes fools and wise men in
the same way. And the fools know it. Oliver Wendell Holmes

On Sun, 10 Jan 2010 17:31:20 +0000, JonG
wrote:

At lunchtime, I noticed that the light on the
boiler was flashing, and the display gave an error code "EA", which
appears to be about as specific as the average Microsoft error code.

From a WB Greenstar manual

Display code:
EA

Description:
Flame not detected.

Remedy:
Is gas cock turned on? Check gas supply pressure,
power supply, igniter electrode and lead, ionisation
sensing electrode and lead, flue duct and CO2 level.

....despite what you said it does sound like a blocked condensate pipe
though


--

Pages from fault manual.

http://img257.imageshack.us/img257/4...tcodepage1.jpg
http://img188.imageshack.us/img188/6...tcodepage2.jpg
http://img33.imageshack.us/img33/534...tcodepage3.jpg
http://img696.imageshack.us/img696/4...tcodepage4.jpg


--

On Sun, 10 Jan 2010 17:31:20 +0000, JonG wrote:

Given the current weather, anyone any ideas what causes problems with
condensing boilers when it isn't the condensate pipe? CAn flue pipes
themselves freeze?

I have a 3-month old Worcester Greenstar CDi COnventional, 30 IIRC. It
is mounted in the cellar, with the tope just below external ground
level. The Flue apparently does a dog-leg within the thick stone walls,
then exits about 12" above ground level, then has an extension kit to
raise the (often dramatic) pluming above window level. The condensate
pipe runs internally under the flooring, and empties into the drainage
sump. I've double checked, this pipe is clear and free-flowing.

There should be a flue gas sampling point on the flue connection just
above the boiler. (There are two caps: one for the air inlet and one for
the flue: you're after the one that communicates with the inner part of
the concentric flue assembly). If you pour water down the flue (not
air) hole it should run away via the condensate syphon/sump and pipework
to the drain. If it doesn't your condensate waste system is blocked
somewhere along the line.

If you've got water in the air intake you may have further difficulties.

--
John Stumbles -- http://yaph.co.uk

I'd rather have a full bottle in front of me
Than a full-frontal lobotomy

"YAPH" wrote in message
...
On Sun, 10 Jan 2010 17:31:20 +0000, JonG wrote:

Given the current weather, anyone any ideas what causes problems with
condensing boilers when it isn't the condensate pipe? CAn flue pipes
themselves freeze?

I have a 3-month old Worcester Greenstar CDi COnventional, 30 IIRC. It
is mounted in the cellar, with the tope just below external ground
level. The Flue apparently does a dog-leg within the thick stone walls,
then exits about 12" above ground level, then has an extension kit to
raise the (often dramatic) pluming above window level. The condensate
pipe runs internally under the flooring, and empties into the drainage
sump. I've double checked, this pipe is clear and free-flowing.

There should be a flue gas sampling point on the flue connection just
above the boiler. (There are two caps: one for the air inlet and one for
the flue: you're after the one that communicates with the inner part of
the concentric flue assembly). If you pour water down the flue (not
air) hole it should run away via the condensate syphon/sump and pipework
to the drain. If it doesn't your condensate waste system is blocked
somewhere along the line.

If you've got water in the air intake you may have further difficulties.

--
John Stumbles -- http://yaph.co.uk

I'd rather have a full bottle in front of me
Than a full-frontal lobotomy

I had the same problem of cutting off, it turned out the condensate pipe was
frozen as it enters the ground sump.
A couple of kettles of boiling water sorted it.

It is a recently installed combi system so I had phoned the installer and he
advised me as he has had numerous call-out for that very thing.

I know nothing of plumbing, however if the condensate pipe is frozen at some
point the condensation maybe backing up and exiting inside your boiler.

"SS" wrote in message
...

"YAPH" wrote in message
...
On Sun, 10 Jan 2010 17:31:20 +0000, JonG wrote:

Given the current weather, anyone any ideas what causes problems with
condensing boilers when it isn't the condensate pipe? CAn flue pipes
themselves freeze?

I have a 3-month old Worcester Greenstar CDi COnventional, 30 IIRC. It
is mounted in the cellar, with the tope just below external ground
level. The Flue apparently does a dog-leg within the thick stone walls,
then exits about 12" above ground level, then has an extension kit to
raise the (often dramatic) pluming above window level. The condensate
pipe runs internally under the flooring, and empties into the drainage
sump. I've double checked, this pipe is clear and free-flowing.

There should be a flue gas sampling point on the flue connection just
above the boiler. (There are two caps: one for the air inlet and one for
the flue: you're after the one that communicates with the inner part of
the concentric flue assembly). If you pour water down the flue (not
air) hole it should run away via the condensate syphon/sump and pipework
to the drain. If it doesn't your condensate waste system is blocked
somewhere along the line.

If you've got water in the air intake you may have further difficulties.

--
John Stumbles -- http://yaph.co.uk

I'd rather have a full bottle in front of me
Than a full-frontal lobotomy

I had the same problem of cutting off, it turned out the condensate pipe
was frozen as it enters the ground sump.
A couple of kettles of boiling water sorted it.

It is a recently installed combi system so I had phoned the installer and
he advised me as he has had numerous call-out for that very thing.

It is incorrecty fitted. It should not ice up.

"Doctor Drivel" wrote in message
...

"SS" wrote in message
...

"YAPH" wrote in message
...
On Sun, 10 Jan 2010 17:31:20 +0000, JonG wrote:

Given the current weather, anyone any ideas what causes problems with
condensing boilers when it isn't the condensate pipe? CAn flue pipes
themselves freeze?

I have a 3-month old Worcester Greenstar CDi COnventional, 30 IIRC. It
is mounted in the cellar, with the tope just below external ground
level. The Flue apparently does a dog-leg within the thick stone walls,
then exits about 12" above ground level, then has an extension kit to
raise the (often dramatic) pluming above window level. The condensate
pipe runs internally under the flooring, and empties into the drainage
sump. I've double checked, this pipe is clear and free-flowing.

There should be a flue gas sampling point on the flue connection just
above the boiler. (There are two caps: one for the air inlet and one for
the flue: you're after the one that communicates with the inner part of
the concentric flue assembly). If you pour water down the flue (not
air) hole it should run away via the condensate syphon/sump and pipework
to the drain. If it doesn't your condensate waste system is blocked
somewhere along the line.

If you've got water in the air intake you may have further difficulties.

--
John Stumbles -- http://yaph.co.uk

I'd rather have a full bottle in front of me
Than a full-frontal lobotomy

I had the same problem of cutting off, it turned out the condensate pipe
was frozen as it enters the ground sump.
A couple of kettles of boiling water sorted it.

It is a recently installed combi system so I had phoned the installer and
he advised me as he has had numerous call-out for that very thing.

It is incorrecty fitted. It should not ice up.

Cant argue with you as I am not a plumber, but from a laymans point of view
if the condensate pipe comes from internal to external in very cold/extreme
conditions then unless it has a heater of some sort on it then surely it is
possible for it to freeze?

Based on what you are saying then there must be a standard that makes it
impossible for it to freeze and if there is would you please advise as I
will take this up with the installer as the boiler is only 6 months old.

"SS" wrote in message
...

"Doctor Drivel" wrote in message
...

"SS" wrote in message
...

"YAPH" wrote in message
...
On Sun, 10 Jan 2010 17:31:20 +0000, JonG wrote:

Given the current weather, anyone any ideas what causes problems with
condensing boilers when it isn't the condensate pipe? CAn flue pipes
themselves freeze?

I have a 3-month old Worcester Greenstar CDi COnventional, 30 IIRC. It
is mounted in the cellar, with the tope just below external ground
level. The Flue apparently does a dog-leg within the thick stone
walls,
then exits about 12" above ground level, then has an extension kit to
raise the (often dramatic) pluming above window level. The condensate
pipe runs internally under the flooring, and empties into the drainage
sump. I've double checked, this pipe is clear and free-flowing.

There should be a flue gas sampling point on the flue connection just
above the boiler. (There are two caps: one for the air inlet and one
for
the flue: you're after the one that communicates with the inner part of
the concentric flue assembly). If you pour water down the flue (not
air) hole it should run away via the condensate syphon/sump and
pipework
to the drain. If it doesn't your condensate waste system is blocked
somewhere along the line.

If you've got water in the air intake you may have further
difficulties.

--
John Stumbles -- http://yaph.co.uk

I'd rather have a full bottle in front of me
Than a full-frontal lobotomy

I had the same problem of cutting off, it turned out the condensate pipe
was frozen as it enters the ground sump.
A couple of kettles of boiling water sorted it.

It is a recently installed combi system so I had phoned the installer
and he advised me as he has had numerous call-out for that very thing.

It is incorrecty fitted. It should not ice up.

Cant argue with you as I am not a plumber, but from a laymans point of
view if the condensate pipe comes from internal to external in very
cold/extreme conditions then unless it has a heater of some sort on it
then surely it is possible for it to freeze?

Based on what you are saying then there must be a standard that makes it
impossible for it to freeze and if there is would you please advise as I
will take this up with the installer as the boiler is only 6 months old.


As you say, any external pipe with the occasional flow of water can freeze.
It is normal practice for a longer run to be of a larger diameter, which
needs a lot more ice to plug the pipe up.

Most condensate traps fill up and empty using a siphon action. The idea is
that you get a few 100 mils of water every so often, rather than a drip, to
lessen the likelihood of freezing.

"SS" wrote in message
...

"Doctor Drivel" wrote in message
...

"SS" wrote in message
...

"YAPH" wrote in message
...
On Sun, 10 Jan 2010 17:31:20 +0000, JonG wrote:

Given the current weather, anyone any ideas what causes problems with
condensing boilers when it isn't the condensate pipe? CAn flue pipes
themselves freeze?

I have a 3-month old Worcester Greenstar CDi COnventional, 30 IIRC. It
is mounted in the cellar, with the tope just below external ground
level. The Flue apparently does a dog-leg within the thick stone
walls,
then exits about 12" above ground level, then has an extension kit to
raise the (often dramatic) pluming above window level. The condensate
pipe runs internally under the flooring, and empties into the drainage
sump. I've double checked, this pipe is clear and free-flowing.

There should be a flue gas sampling point on the flue connection just
above the boiler. (There are two caps: one for the air inlet and one
for
the flue: you're after the one that communicates with the inner part of
the concentric flue assembly). If you pour water down the flue (not
air) hole it should run away via the condensate syphon/sump and
pipework
to the drain. If it doesn't your condensate waste system is blocked
somewhere along the line.

If you've got water in the air intake you may have further
difficulties.

--
John Stumbles -- http://yaph.co.uk

I'd rather have a full bottle in front of me
Than a full-frontal lobotomy

I had the same problem of cutting off, it turned out the condensate pipe
was frozen as it enters the ground sump.
A couple of kettles of boiling water sorted it.

It is a recently installed combi system so I had phoned the installer
and he advised me as he has had numerous call-out for that very thing.

It is incorrecty fitted. It should not ice up.

Cant argue with you as I am not a plumber, but from a laymans point of
view if the condensate pipe comes from internal to external in very
cold/extreme conditions then unless it has a heater of some sort on it
then surely it is possible for it to freeze?

Based on what you are saying then there must be a standard that makes it
impossible for it to freeze and if there is would you please advise as I
will take this up with the installer as the boiler is only 6 months old.

The external pipe should be 32mm to prevent freezing. And external
insulation where necessary. All in regs. It should also be in the makers
instructions.

A recent thread went over all this.

Doctor Drivel wrote:

The external pipe should be 32mm to prevent freezing. And external
insulation where necessary. All in regs. It should also be in the makers
instructions.

Any suggestions on the most suitable insulation to use?

Chris
--
Chris J Dixon Nottingham UK


Have dancing shoes, will ceilidh.

"Chris J Dixon" wrote in message
...
Doctor Drivel wrote:

The external pipe should be 32mm to prevent freezing. And external
insulation where necessary. All in regs. It should also be in the makers
instructions.

Any suggestions on the most suitable insulation to use?

Chris
--
Chris J Dixon Nottingham UK


Have dancing shoes, will ceilidh.

Well I have the 32 mm pipe and is about 9 inches from where it exits outside
to the trap so I will get something for way of insulation.

In article ,
Chris J Dixon writes:
Any suggestions on the most suitable insulation to use?

Externally, you need to use a waterproof insulation so it can't
become waterlogged, also known as closed-cell. This is most commonly
used on chilled aircon pipework. Armaflex is best known make.

Internally, it doesn't much matter.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

"Andrew Gabriel" wrote in message
...
In article ,
Chris J Dixon writes:
Any suggestions on the most suitable insulation to use?

Externally, you need to use a waterproof insulation so it can't
become waterlogged, also known as closed-cell. This is most commonly
used on chilled aircon pipework. Armaflex is best known make.

Remember insulation only makes it less likely to freeze up and a prolonged
cold spell could still see the pipes freezing.
Make sure you can remove and refit it in case you have to thaw it.
IIRC in ~1970 there were about 22 days where it was below freezing day and
night.
I was recording weather stuff for a school project and the wet bulb never
defrosted over that period.
That was in west bromwich not the Scottish highlands.

Armaflex is closed cell (which means it can't absorb moisture and
itself freeze worsening the problem).

However if used outdoor it needs to be painted.
I am not sure if that is re UV or Fire Retardancy although it meets BR
"O" rating.

On Mon, 11 Jan 2010 08:53:03 -0000, SS wrote:

"Chris J Dixon" wrote in message
...
Doctor Drivel wrote:

The external pipe should be 32mm to prevent freezing. And external
insulation where necessary. All in regs. It should also be in the makers
instructions.

Any suggestions on the most suitable insulation to use?

Chris
--
Chris J Dixon Nottingham UK


Have dancing shoes, will ceilidh.

Well I have the 32 mm pipe and is about 9 inches from where it exits outside
to the trap so I will get something for way of insulation.

Mine drain pipe comes through the wall a course or so above dpc, then drops
to outside slabs level using 2 x 45 elbows, then on to a gully about a
metre or so sway. I've not had any trouble with freezing, even though the
drain pipe has had a covering of snow at times.


--
The Wanderer

When you hear the toilet flush and your child says 'Uh oh'
It's already too late!

"Andrew Gabriel" wrote in message
...
In article ,
Chris J Dixon writes:
Any suggestions on the most suitable insulation to use?

Externally, you need to use a waterproof insulation so it can't
become waterlogged, also known as closed-cell. This is most commonly
used on chilled aircon pipework. Armaflex is best known make.

Internally, it doesn't much matter.

Unless it is in a vented loft.

On 11/01/10 10:28, js.b1 wrote:

Armaflex is closed cell (which means it can't absorb moisture and
itself freeze worsening the problem).
However if used outdoor it needs to be painted.

For computer room aircon drains I often see it foil wrapped instead.

On Mon, 11 Jan 2010 01:58:46 -0000, "Doctor Drivel"
wrote:


The external pipe should be 32mm to prevent freezing. And external
insulation where necessary. All in regs. It should also be in the makers
instructions.

A number of Worcester Bosch models require 21mm* plastic pipe for the
condenser drain, there is nothing in the installations instructions
about terminating it to 32mm (are such adaptors even available?)

Yes 21mm, bloody funny size but available from the sheds, but not from
BES.


--

"Mike" wrote in message
...
On Mon, 11 Jan 2010 01:58:46 -0000, "Doctor Drivel"
wrote:


The external pipe should be 32mm to prevent freezing. And external
insulation where necessary. All in regs. It should also be in the makers
instructions.

A number of Worcester Bosch models require 21mm plastic pipe for the
condenser drain, there is nothing in the installations instructions
about terminating it to 32mm (are such adaptors even available?)

Yes 21mm, bloody funny size but available from the sheds, but not from
BES.

21mm is overflow pipe size. When running it externally it should be 32mm.
21.5mm to 32mm:
BES Nos: 11939 or
11940 for the 40mm

A soakaway can be made by using a larger pipe with holes in one side to
divert water away from the house. Cheaper than buying one.