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Default Boiler flue & rain ingress

Hello,

I think that when it rains hard in a certain direction the flue on my
condenser boiler lets in rain water. This then runs through the boiler and
drips out from the bottom front corner. Does this sound possible? It is
definitely rain water as it never happens when it is not raining.

Any ideas on how I can prevent this?


Thanks,

Graham

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Default Boiler flue & rain ingress


"Graham Jones" wrote in message
...
Hello,

I think that when it rains hard in a certain direction the flue on my
condenser boiler lets in rain water. This then runs through the boiler and
drips out from the bottom front corner. Does this sound possible? It is
definitely rain water as it never happens when it is not raining.

Any ideas on how I can prevent this?


Thanks,

Graham


When you consider that the boiler itself should be completely sealed, then
the water dripping from the corner of the casing is most likely coming
through a gap between the flue pipe and the brickwork of the wall. Is there
a collar around the outside of the flue? If not, then some sealant, in the
form of some sand and cement mortar, might be a good idea.



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Default Boiler flue & rain ingress

In article ,
Graham Jones wrote:
I think that when it rains hard in a certain direction the flue on my
condenser boiler lets in rain water. This then runs through the boiler
and drips out from the bottom front corner. Does this sound possible?
It is definitely rain water as it never happens when it is not raining.


If this is happening you have a serious problem which should be
investigated immediately. The flue is connected (obviously) to the
combustion chamber and that combination should be totally sealed to the
room. It could be water is leaking round the outside of the flue and
finding its way into the room from there. But that too should be sealed.
Or, of course, the condensate drain if it's a condensing boiler.

--
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Default Boiler flue & rain ingress

Dave Plowman (News) wrote:
In article ,
Graham Jones wrote:
I think that when it rains hard in a certain direction the flue on my
condenser boiler lets in rain water. This then runs through the boiler
and drips out from the bottom front corner. Does this sound possible?
It is definitely rain water as it never happens when it is not raining.


If this is happening you have a serious problem which should be
investigated immediately. The flue is connected (obviously) to the
combustion chamber and that combination should be totally sealed to the
room. It could be water is leaking round the outside of the flue and
finding its way into the room from there. But that too should be sealed.
Or, of course, the condensate drain if it's a condensing boiler.


Yes I've experienced similar myself, where I've had a leak at the bottom
of the boiler which I've traced back to condensate running back along
the (near-horizontal) flue and emerging from the outer sheath of the
flue, above the boiler due to a failed 0-ring there. No big safety
issue there. I imagine that incoming rain would/could follow the same
route.

Also, I've been whinged at by CORGISs about my boiler flue not being far
enough away from a facing wall (it's about 0.6 m away) - I've been told
that this is close enough for steam/condensate to be pushed back down
the flue. If that's plausible, then I'm sure incoming rain is too!

David
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Default Boiler flue & rain ingress

Thanks for all your replies. Luckily the boiler is in the garage and not in
the house, but I will put a CO detector in there. The outside of the flue
does have a collar and is also sealed with brown silicon. No rain today and
no leaks, so definitely rain water.

The water is coming from the front right corner of what the installation
manual calls the air box, where the fan and condensate trap are located.
Does this provide any clues?

Also on a side note, why do boilers and fires require flues but not gas
ovens? I have always wondered about this.


Thanks,

Graham




"Graham Jones" wrote in message
...
Hello,

I think that when it rains hard in a certain direction the flue on my
condenser boiler lets in rain water. This then runs through the boiler and
drips out from the bottom front corner. Does this sound possible? It is
definitely rain water as it never happens when it is not raining.

Any ideas on how I can prevent this?


Thanks,

Graham




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Default Boiler flue & rain ingress



"Graham Jones" wrote in message
...
Thanks for all your replies. Luckily the boiler is in the garage and not
in the house, but I will put a CO detector in there. The outside of the
flue does have a collar and is also sealed with brown silicon. No rain
today and no leaks, so definitely rain water.

The water is coming from the front right corner of what the installation
manual calls the air box, where the fan and condensate trap are located.
Does this provide any clues?

Also on a side note, why do boilers and fires require flues but not gas
ovens? I have always wondered about this.


They are regarded as small intermittent use devices and they rely on
adequate ventilation.
There is nothing dangerous given off when you burn gas properly with plenty
of fresh air.

It does give off a huge amount of water vapour which will make everything
mould if you use it for heating without throwing most of the heat away with
ventilation.



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Default Boiler flue & rain ingress


"Graham Jones" wrote in message
...
Thanks for all your replies. Luckily the boiler is in the garage and not

in
the house, but I will put a CO detector in there. The outside of the flue
does have a collar and is also sealed with brown silicon. No rain today

and
no leaks, so definitely rain water.

The water is coming from the front right corner of what the installation
manual calls the air box, where the fan and condensate trap are located.
Does this provide any clues?

Also on a side note, why do boilers and fires require flues but not gas
ovens? I have always wondered about this.


Thanks,

Graham


Boilers are usually sealed units. Where the air is drawn in from outside
and expelled back outside through the flue. Not all boilers are like that,
but most today are. This reduces the need to have permanently open vents in
the same room as the boiler, so keep draughts out when you want it warm
inside.

Gas fires and stoves need a permanently open vent from outside, into the
room where they are installed. If you haven't go one on an outside facing
wall, then provision has to be made for a forced air intake and outlet
system into the room where the gas appliance is installed. A gas fire must
also have a flue to the outside, with other safety regulations that go along
with it.

Did you think it was as simple as fitting a stove in a cupboard under the
stairs, and that's it? There is a lot more to gas safety regulations than
that. :-)

I'm sure more knowledgeable others will go into more details for you.
Telling of how the extraction does this, while the Bunsen effect makes it do
that. But I'll leave it there. :-)


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Default Boiler flue & rain ingress

I was wrong, it is leaking from the boiler but intermittently. Maybe
condensate then?

"Graham Jones" wrote in message
...
Thanks for all your replies. Luckily the boiler is in the garage and not
in the house, but I will put a CO detector in there. The outside of the
flue does have a collar and is also sealed with brown silicon. No rain
today and no leaks, so definitely rain water.

The water is coming from the front right corner of what the installation
manual calls the air box, where the fan and condensate trap are located.
Does this provide any clues?

Also on a side note, why do boilers and fires require flues but not gas
ovens? I have always wondered about this.


Thanks,

Graham




"Graham Jones" wrote in message
...
Hello,

I think that when it rains hard in a certain direction the flue on my
condenser boiler lets in rain water. This then runs through the boiler
and drips out from the bottom front corner. Does this sound possible? It
is definitely rain water as it never happens when it is not raining.

Any ideas on how I can prevent this?


Thanks,

Graham



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Default Boiler flue & rain ingress


"Graham Jones" wrote in message
...
I was wrong, it is leaking from the boiler but intermittently. Maybe
condensate then?


Is the condensate not removed with pipework to the outside? If not, then
get a pipe installed to remove it safely to a drain point.

If you have pipework for this purpose, then make sure rain is not
overflowing into it and back into the boiler. That may be why you are
noticing this problem more when it rains.


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Default Boiler flue & rain ingress

In article ,
"Graham Jones" writes:
I was wrong, it is leaking from the boiler but intermittently. Maybe
condensate then?


Could be condensate or water from the heating system.

Condensate is relatively corrosive, so steel metalwork it
comes in contact with rusts quickly. In time, it can corrode
through sealed casings, rendering them unservicable.

With my Keston, I check for leaking condensate by leaving the
hosepipe trickling slowly into the end of the flue outlet. The
water should pass through and away down the condensate drain.
Make sure it is (don't let it fill up the heat exchanger or it
will likely damage the ignitor and gas parts). Make sure you don't
run water into the boiler air intake instead of the flue outlet.

I don't know how suitable this test is with other condensing
boilers. Boilers which pump out the condensate might not do so
when the burner isn't firing or the power is off for servicing.
At your own risk, as they say.

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


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Default Boiler flue & rain ingress

On Nov 10, 12:40*pm, "Graham Jones" wrote:
I was wrong, it is leaking from the boiler but intermittently. Maybe
condensate then?

"Graham Jones" wrote in message

...



Thanks for all your replies. Luckily the boiler is in the garage and not
in the house, but I will put a CO detector in there. The outside of the
flue does have a collar and is also sealed with brown silicon. No rain
today and no leaks, so definitely rain water.


The water is coming from the front right corner of what the installation
manual calls the air box, where the fan and condensate trap are located..
Does this provide any clues?


Also on a side note, why do boilers and fires require flues but not gas
ovens? I have always wondered about this.


Thanks,


Graham


"Graham Jones" wrote in message
.. .
Hello,


I think that when it rains hard in a certain direction the flue on my
condenser boiler lets in rain water. This then runs through the boiler
and drips out from the bottom front corner. Does this sound possible? It
is definitely rain water as it never happens when it is not raining.


Any ideas on how I can prevent this?


Thanks,


Graham- Hide quoted text -


- Show quoted text -


I asked recently about rain ingress as my new boiler has been fitted
with a flue that points upwards, about 5 degress from horizontal,
which to my mind is bound to see some rain come in.

It was pointed out (helpfully by most!) that that is the right way to
fit the flue for the boiler that I have (of course, others may be
different). And the same point about condensate was made.

Hope that helps!

Matt
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Default Boiler flue & rain ingress

Thanks for the reply, it begs the question, which part of the flue is the
outlet and which is the air intake?

"Andrew Gabriel" wrote in message
...
In article ,
"Graham Jones" writes:
I was wrong, it is leaking from the boiler but intermittently. Maybe
condensate then?


Could be condensate or water from the heating system.

Condensate is relatively corrosive, so steel metalwork it
comes in contact with rusts quickly. In time, it can corrode
through sealed casings, rendering them unservicable.

With my Keston, I check for leaking condensate by leaving the
hosepipe trickling slowly into the end of the flue outlet. The
water should pass through and away down the condensate drain.
Make sure it is (don't let it fill up the heat exchanger or it
will likely damage the ignitor and gas parts). Make sure you don't
run water into the boiler air intake instead of the flue outlet.

I don't know how suitable this test is with other condensing
boilers. Boilers which pump out the condensate might not do so
when the burner isn't firing or the power is off for servicing.
At your own risk, as they say.

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


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Default Boiler flue & rain ingress

"Graham Jones" wrote in message
...
Hello,

I think that when it rains hard in a certain direction the flue on my
condenser boiler lets in rain water. This then runs through the boiler and
drips out from the bottom front corner. Does this sound possible? It is
definitely rain water as it never happens when it is not raining.

Any ideas on how I can prevent this?


Thanks,

Graham


Today I tried to find the source of the leak, I stripped the boiler down as
far as I dared. It seems to be coming down the righthand side of the inside
of the air box, between the air box and the combustion box.

So I reckon it is either from the flow or return into the heat exchanger or
something to do with condensate from the flue at the top. The condensate
trap seems to be filling and emptying correctly and is clear of debris.

The next stage I reckon would be to remove the heat exchanger assembly, but
for this I would need to drain down. The wife wants to call someone in, I am
near to agreeing with her.

One question, as the water in the system is under pressure then wouldn't the
leak drip all the time rather than just when the boiler is operating? If so
then it must be condensate, mustn't it?

Graham

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"Graham Jones" wrote in message
...
Thanks for the reply, it begs the question, which part of the flue is the
outlet and which is the air intake?

Inner pipe out. Outer pipe in.

A bit like "righty tighty, lefty loosey" to remember the way a screw, nut or
bolt turns.



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"Graham Jones" wrote in message
...
snipped

Today I tried to find the source of the leak, I stripped the boiler down

as
far as I dared. It seems to be coming down the righthand side of the

inside
of the air box, between the air box and the combustion box.

So I reckon it is either from the flow or return into the heat exchanger

or
something to do with condensate from the flue at the top. The condensate
trap seems to be filling and emptying correctly and is clear of debris.

The next stage I reckon would be to remove the heat exchanger assembly,

but
for this I would need to drain down. The wife wants to call someone in, I

am
near to agreeing with her.

One question, as the water in the system is under pressure then wouldn't

the
leak drip all the time rather than just when the boiler is operating? If

so
then it must be condensate, mustn't it?

Graham

Or rain running along the inside of the outer pipe on the flue. Is there
any water mark along the inside bottom of the pipe? Or any water marking at
all along the flue pipes? If it's condensate, you should see where it has
been dripping or running along the metal, as it leaves a bit of a mess
behind because of what contains.




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Default Boiler flue & rain ingress

replying to BigWallop, Phillip Ellis wrote:
We have had water coming down inside of flue that damages gas valve, replaced
twice. Now waiting for the next occurrence! Is there a flue that would prevent
it happening?

--
for full context, visit https://www.homeownershub.com/uk-diy...ss-519194-.htm


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Default Boiler flue & rain ingress

On 13/11/2018 12:44, Phillip Ellis wrote:
replying to BigWallop, Phillip Ellis wrote:
We have had water coming down inside of flue that damages gas valve,
replaced
twice. Now waiting for the next occurrence! Is there a flue that would
prevent
it happening?


Golly. Only 10 years old post.

What ever happened to Big Wallop?


--
€œI know that most men, including those at ease with problems of the
greatest complexity, can seldom accept even the simplest and most
obvious truth if it be such as would oblige them to admit the falsity of
conclusions which they have delighted in explaining to colleagues, which
they have proudly taught to others, and which they have woven, thread by
thread, into the fabric of their lives.€

ۥ Leo Tolstoy
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Default Boiler flue & rain ingress

On 13/11/2018 12:44, Phillip Ellis wrote:
replying to BigWallop, Phillip Ellis wrote:
We have had water coming down inside of flue that damages gas valve,
replaced
twice. Now waiting for the next occurrence! Is there a flue that would
prevent
it happening?


Start a new thread, and post details of your boiler make and flue type...


--
Cheers,

John.

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