At some stage I am going to need a replacement heat exchanger for an elderly
but otherwise in GWO Baxi Bermuda 45/4E BBU.

Baxi have confirmed that neither the original part (Baxi part no. 233910, GC
no. 193156) or its replacement (Baxi part no. 248436, GC no. 193156, now
classified as 'obsolete') are available.

I have checked with many UK heating parts suppliers who stock genuine Baxi
parts. None have this part or can get hold of it.

My question is: Are there any third party manufacturers/suppliers, in the UK
or abroad, who can supply a compatible part? In the past I'm sure I read
that there were Chinese manufacturers of Baxi compatible parts but I have
not managed find any references for this particular part.

Many thanks
Tom

Ps. Before anyone comments, I know that BBUs are less efficient than modern
wall mounted condensing boilers.
Pps. The email address in the header is just a spam-trap.
--
Tom Crane, Dept. Physics, Royal Holloway, University of London, Egham Hill,
Egham, Surrey, TW20 0EX, England.
Email: T dot Crane at rhul dot ac dot uk

<Use-Author-Supplied-Address-Header@[127.1]> wrote:
> At some stage I am going to need a replacement heat exchanger for an elderly
> but otherwise in GWO Baxi Bermuda 45/4E BBU.
>
> Baxi have confirmed that neither the original part (Baxi part no. 233910, GC
> no. 193156) or its replacement (Baxi part no. 248436, GC no. 193156, now
> classified as 'obsolete') are available.
>
> I have checked with many UK heating parts suppliers who stock genuine Baxi
> parts. None have this part or can get hold of it.
>
> My question is: Are there any third party manufacturers/suppliers, in the UK
> or abroad, who can supply a compatible part? In the past I'm sure I read
> that there were Chinese manufacturers of Baxi compatible parts but I have
> not managed find any references for this particular part.
>
> Many thanks
> Tom
>
> Ps. Before anyone comments, I know that BBUs are less efficient than modern
> wall mounted condensing boilers.
> Pps. The email address in the header is just a spam-trap.

Whilst I can empathise with keeping an old any trusty appliance going, when
it comes to the Baxi Bermuda I really do think it’s time to thank it for
its long years of service and sling it in a skip (when it dies). That or
turn it into an “installation” in Tate Modern.

Do you plan to replace the heat exchanger yourself? Even if you do manage
to find a Chinese heat exchanger you might well find it difficult to find a
fitter who will fit a heat exchanger to such an obsolete boiler.

Tim

--
Please don't feed the trolls

On Sunday, December 10, 2023 at 9:17:40 PM UTC, Use-Author-Suppli....@127.1 wrote:
> At some stage I am going to need a replacement heat exchanger for an elderly
> but otherwise in GWO Baxi Bermuda 45/4E BBU.
>
> Baxi have confirmed that neither the original part (Baxi part no. 233910, GC
> no. 193156) or its replacement (Baxi part no. 248436, GC no. 193156, now
> classified as 'obsolete') are available.
>
> I have checked with many UK heating parts suppliers who stock genuine Baxi
> parts. None have this part or can get hold of it.
>
> My question is: Are there any third party manufacturers/suppliers, in the UK
> or abroad, who can supply a compatible part? In the past I'm sure I read
> that there were Chinese manufacturers of Baxi compatible parts but I have
> not managed find any references for this particular part.
>
> Many thanks
> Tom
>
> Ps. Before anyone comments, I know that BBUs are less efficient than modern
> wall mounted condensing boilers.
> Pps. The email address in the header is just a spam-trap.
> --
> Tom Crane, Dept. Physics, Royal Holloway, University of London, Egham Hill,
> Egham, Surrey, TW20 0EX, England.
> Email: T dot Crane at rhul dot ac dot uk

Wow - I think this is the same Baxi Bermuda back boiler that we have...

I am not looking forward to it giving up the ghost, but I am *definitely* not
planning to replace it like-for-like...

J^n

On Sunday 10 December 2023 at 21:17:40 UTC, Use-Author-Suppli...@127.1 wrote:
> At some stage I am going to need a replacement heat exchanger for an elderly
> but otherwise in GWO Baxi Bermuda 45/4E BBU.
>
> Baxi have confirmed that neither the original part (Baxi part no. 233910, GC
> no. 193156) or its replacement (Baxi part no. 248436, GC no. 193156, now
> classified as 'obsolete') are available.
>
> I have checked with many UK heating parts suppliers who stock genuine Baxi
> parts. None have this part or can get hold of it.
>
> My question is: Are there any third party manufacturers/suppliers, in the UK
> or abroad, who can supply a compatible part? In the past I'm sure I read
> that there were Chinese manufacturers of Baxi compatible parts but I have
> not managed find any references for this particular part.
>
> Many thanks
> Tom
>
> Ps. Before anyone comments, I know that BBUs are less efficient than modern
> wall mounted condensing boilers.
> Pps. The email address in the header is just a spam-trap.

There are companies that make HXes & could copy yours. I doubt any uk company would do it, someone in shenzhen surely would. Indeed mfr of some types of HX is not difficult. The legal ramifications are beyond me, that's for you to find out about.

On 10/12/2023 21:00, Use-Author-Supplied-Address-Header@[127.1] wrote:
> At some stage I am going to need a replacement heat exchanger for an elderly
> but otherwise in GWO Baxi Bermuda 45/4E BBU.
>
> Baxi have confirmed that neither the original part (Baxi part no. 233910, GC
> no. 193156) or its replacement (Baxi part no. 248436, GC no. 193156, now
> classified as 'obsolete') are available.
>
> I have checked with many UK heating parts suppliers who stock genuine Baxi
> parts. None have this part or can get hold of it.

Can be worth checking with these folks - they seem to have a reasonably
regular flow of recon parts:

https://boilerrecycling.co.uk/product-category/heat-exchangers?filter_brand=baxi

--
Cheers,

John.

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

On 10/12/2023 21:00, Use-Author-Supplied-Address-Header@[127.1] wrote:
> At some stage I am going to need a replacement heat exchanger for an elderly
> but otherwise in GWO Baxi Bermuda 45/4E BBU.
>
> Baxi have confirmed that neither the original part (Baxi part no. 233910, GC
> no. 193156) or its replacement (Baxi part no. 248436, GC no. 193156, now
> classified as 'obsolete') are available.
>
> I have checked with many UK heating parts suppliers who stock genuine Baxi
> parts. None have this part or can get hold of it.
>
> My question is: Are there any third party manufacturers/suppliers, in the UK
> or abroad, who can supply a compatible part? In the past I'm sure I read
> that there were Chinese manufacturers of Baxi compatible parts but I have
> not managed find any references for this particular part.
>
> Many thanks
> Tom
>
> Ps. Before anyone comments, I know that BBUs are less efficient than modern
> wall mounted condensing boilers.
> Pps. The email address in the header is just a spam-trap.

By way of example the 248436 is a 26 fin heat exchanger and new will
cost £5-600.

While it is admirable to effect a repair, the economics of running an
old boiler, plus the cost of this part assuming you can get it, makes it
a no-brainer to upgrade to a more modern boiler.

On 11 Dec 2023 at 00:59:27 GMT, Fredxx wrote:

> On 10/12/2023 21:00, Use-Author-Supplied-Address-Header@[127.1] wrote:
>> At some stage I am going to need a replacement heat exchanger for an elderly
>> but otherwise in GWO Baxi Bermuda 45/4E BBU.
>>
>> Baxi have confirmed that neither the original part (Baxi part no. 233910, GC
>> no. 193156) or its replacement (Baxi part no. 248436, GC no. 193156, now
>> classified as 'obsolete') are available.
>>
>> I have checked with many UK heating parts suppliers who stock genuine Baxi
>> parts. None have this part or can get hold of it.
>>
>> My question is: Are there any third party manufacturers/suppliers, in the UK
>> or abroad, who can supply a compatible part? In the past I'm sure I read
>> that there were Chinese manufacturers of Baxi compatible parts but I have
>> not managed find any references for this particular part.
>>
>> Many thanks
>> Tom
>>
>> Ps. Before anyone comments, I know that BBUs are less efficient than modern
>> wall mounted condensing boilers.
>> Pps. The email address in the header is just a spam-trap.
>
> By way of example the 248436 is a 26 fin heat exchanger and new will
> cost £5-600.
>

Ratther less than that? -

https://www.warmsafeplumbingandheating.co.uk/product/baxi-bermuda-248436-20-fin-heat-exchanger-spares/

And I had a measure (in sense I was given an instant refund when a part didn't
work) of success with pulls on ebay.

> While it is admirable to effect a repair, the economics of running an
> old boiler, plus the cost of this part assuming you can get it, makes it
> a no-brainer to upgrade to a more modern boiler.

Maybe. After the logic board I'd have thought the heat exchanger was the only
£100 plus component?
--
Cheers, Rob, Sheffield UK

Fredxx <fredxx@spam.invalid> wrote:
> By way of example the 248436 is a 26 fin heat exchanger and new will
> cost £5-600.
>
> While it is admirable to effect a repair, the economics of running an
> old boiler, plus the cost of this part assuming you can get it, makes it
> a no-brainer to upgrade to a more modern boiler.

I would agree, although the one we had was located in the chimney breast in
the living room. Installing a regular boiler would have meant moving it (to
an outside wall, likely in the kitchen), re-piping the heating and gas to
get there, and then doing something with the gaping hole in the fireplace.
(potentially adding a gas fire if you used that function)

That's a lot more work than just replacing a heat exchanger.

Another thought would be, if you're going to have to relocate the boiler
anyway, it might be worth looking at a heat pump. It might be say 2x
disruption compared to moving the boiler, but the unit can go outside which
might give you more options compared with a boiler that needs to be inside.

I agree with not throwing good money after bad though. If I were the OP,
since the boiler is still working, I'd probably be planning my next move -
which would likely mean something more substantial than trying to source a
heat exchanger to keep the old girl staggering along.

Theo

On 11/12/2023 11:29, Theo wrote:
> Fredxx <fredxx@spam.invalid> wrote:
>> By way of example the 248436 is a 26 fin heat exchanger and new will
>> cost £5-600.
>>
>> While it is admirable to effect a repair, the economics of running an
>> old boiler, plus the cost of this part assuming you can get it, makes it
>> a no-brainer to upgrade to a more modern boiler.
>
> I would agree, although the one we had was located in the chimney breast in
> the living room. Installing a regular boiler would have meant moving it (to
> an outside wall, likely in the kitchen), re-piping the heating and gas to
> get there, and then doing something with the gaping hole in the fireplace.
> (potentially adding a gas fire if you used that function)
>
> That's a lot more work than just replacing a heat exchanger.
>
> Another thought would be, if you're going to have to relocate the boiler
> anyway, it might be worth looking at a heat pump. It might be say 2x
> disruption compared to moving the boiler, but the unit can go outside which
> might give you more options compared with a boiler that needs to be inside.

There are boilers designed for external installation as well...

--
Cheers,

John.

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

Theo <theom+news@chiark.greenend.org.uk> wrote:
: Fredxx <fredxx@spam.invalid> wrote:
: > By way of example the 248436 is a 26 fin heat exchanger and new will
: > cost ?5-600.
: >
: > While it is admirable to effect a repair, the economics of running an
: > old boiler, plus the cost of this part assuming you can get it, makes it
: > a no-brainer to upgrade to a more modern boiler.

: I would agree, although the one we had was located in the chimney breast in
: the living room. Installing a regular boiler would have meant moving it (to
: an outside wall, likely in the kitchen), re-piping the heating and gas to
: get there, and then doing something with the gaping hole in the fireplace.
: (potentially adding a gas fire if you used that function)

: That's a lot more work than just replacing a heat exchanger.

: Another thought would be, if you're going to have to relocate the boiler
: anyway, it might be worth looking at a heat pump. It might be say 2x
: disruption compared to moving the boiler, but the unit can go outside which
: might give you more options compared with a boiler that needs to be inside.

: I agree with not throwing good money after bad though. If I were the OP,
: since the boiler is still working, I'd probably be planning my next move -
: which would likely mean something more substantial than trying to source a
: heat exchanger to keep the old girl staggering along.

My thanks to everyone who followed-up. There were some useful pointers.

I'll check out
https://boilerrecycling.co.uk/product-category/heat-exchangers?filter_brand=baxi
soon.

My main problem with a wall mounted condensing boiler is that there is
nowhere it could be installed without significantly spoiling the room it
would have to go in, probably the kitchen. As you suggest there is a lot
more work, plumbing involved. The built-in obsolescence of modern boilers
also irritates me. Our current one must be about 50 years old. No modern
condensing one is going to even get close to that!

It is pity that Baxi discontinued their 'HE' BBU which would have been
something at least worth considering.

The BG engineer who serviced it said the heat exchanger had a tiny leak and
that at some stage it will fail. The trouble is I don't have any idea when.
Unfortunately I was out at work when he came (due to BG's admin mistake) so
did not get a chance to see where the leak was myself and ask him about it.

I am not even very sure of the construction of this particular HE, from
photos on suppliers websites and the engineering drawings on Baxi's website.
It appears to consist of two (upper and lower) cast iron sections held
together with bolts. I read elsewhere that some kind of gaskets may be
involved in sealing the two sections together, and that any leaks would be
more likely in/around the gaskets (which presumably can be replaced?) rather
than in the the cast iron sections. I've really no idea though. I would be
interested to know if anyone has taken one of these apart or has seen one
close up.

Cheers
Tom

: Theo

Ps. The email address in the header is just a spam-trap.
--
Tom Crane, Dept. Physics, Royal Holloway, University of London, Egham Hill,
Egham, Surrey, TW20 0EX, England.
Email: T dot Crane at rhul dot ac dot uk

On 11/12/2023 20:29, John Rumm wrote:
> On 11/12/2023 11:29, Theo wrote:
>> Fredxx <fredxx@spam.invalid> wrote:
>>> By way of example the 248436 is a 26 fin heat exchanger and new will
>>> cost £5-600.
>>>
>>> While it is admirable to effect a repair, the economics of running an
>>> old boiler, plus the cost of this part assuming you can get it, makes it
>>> a no-brainer to upgrade to a more modern boiler.
>>
>> I would agree, although the one we had was located in the chimney
>> breast in
>> the living room.  Installing a regular boiler would have meant moving
>> it (to
>> an outside wall, likely in the kitchen), re-piping the heating and gas to
>> get there, and then doing something with the gaping hole in the
>> fireplace.
>> (potentially adding a gas fire if you used that function)
>>
>> That's a lot more work than just replacing a heat exchanger.
>>
>> Another thought would be, if you're going to have to relocate the boiler
>> anyway, it might be worth looking at a heat pump.  It might be say 2x
>> disruption compared to moving the boiler, but the unit can go outside
>> which
>> might give you more options compared with a boiler that needs to be
>> inside.
>
> There are boilers designed for external installation as well...
>
>

Yes, I have seen people have external oil fueleld boilers..

How do they prevent these from freezing & springing a leak during cold
snaps when not running?

On 12/12/2023 08:50, SH wrote:
> On 11/12/2023 20:29, John Rumm wrote:
>> On 11/12/2023 11:29, Theo wrote:
>>> Fredxx <fredxx@spam.invalid> wrote:
>>>> By way of example the 248436 is a 26 fin heat exchanger and new will
>>>> cost £5-600.
>>>>
>>>> While it is admirable to effect a repair, the economics of running an
>>>> old boiler, plus the cost of this part assuming you can get it,
>>>> makes it
>>>> a no-brainer to upgrade to a more modern boiler.
>>>
>>> I would agree, although the one we had was located in the chimney
>>> breast in
>>> the living room.  Installing a regular boiler would have meant moving
>>> it (to
>>> an outside wall, likely in the kitchen), re-piping the heating and
>>> gas to
>>> get there, and then doing something with the gaping hole in the
>>> fireplace.
>>> (potentially adding a gas fire if you used that function)
>>>
>>> That's a lot more work than just replacing a heat exchanger.
>>>
>>> Another thought would be, if you're going to have to relocate the boiler
>>> anyway, it might be worth looking at a heat pump.  It might be say 2x
>>> disruption compared to moving the boiler, but the unit can go outside
>>> which
>>> might give you more options compared with a boiler that needs to be
>>> inside.
>>
>> There are boilers designed for external installation as well...
>>
>>
>
>
> Yes, I have seen people have external oil fueleld boilers..
>
> How do they prevent these from freezing & springing a leak during cold
> snaps when not running?

In general in cold snaps they *are* running. I believe its something to
to with 'Fizzix'.

And they are in insulated housings...and have quite a lot of thermal mass.

How do you stop your house, which is after all outside, from freezing in
a 'cold snap'?

Oh, and of course they have frost stats and will fire up very
occasionally ...

--
"Nature does not give up the winter because people dislike the cold."

― Confucius

<Use-Author-Supplied-Address-Header@[127.1]> wrote:
> Theo <theom+news@chiark.greenend.org.uk> wrote:
>> Fredxx <fredxx@spam.invalid> wrote:
>>> By way of example the 248436 is a 26 fin heat exchanger and new will
>>> cost ?5-600.
>>>
>>> While it is admirable to effect a repair, the economics of running an
>>> old boiler, plus the cost of this part assuming you can get it, makes it
>>> a no-brainer to upgrade to a more modern boiler.
>
>> I would agree, although the one we had was located in the chimney breast in
>> the living room. Installing a regular boiler would have meant moving it (to
>> an outside wall, likely in the kitchen), re-piping the heating and gas to
>> get there, and then doing something with the gaping hole in the fireplace.
>> (potentially adding a gas fire if you used that function)
>
>> That's a lot more work than just replacing a heat exchanger.
>
>> Another thought would be, if you're going to have to relocate the boiler
>> anyway, it might be worth looking at a heat pump. It might be say 2x
>> disruption compared to moving the boiler, but the unit can go outside which
>> might give you more options compared with a boiler that needs to be inside.
>
>> I agree with not throwing good money after bad though. If I were the OP,
>> since the boiler is still working, I'd probably be planning my next move -
>> which would likely mean something more substantial than trying to source a
>> heat exchanger to keep the old girl staggering along.
>
> My thanks to everyone who followed-up. There were some useful pointers.
>
> I'll check out
> https://boilerrecycling.co.uk/product-category/heat-exchangers?filter_brand=baxi
> soon.
>
> My main problem with a wall mounted condensing boiler is that there is
> nowhere it could be installed without significantly spoiling the room it
> would have to go in, probably the kitchen. As you suggest there is a lot
> more work, plumbing involved. The built-in obsolescence of modern boilers
> also irritates me. Our current one must be about 50 years old. No modern
> condensing one is going to even get close to that!

Maybe outside mounting is worth considering? Relatively rare for gas
boilers here but it seemed to be he normally in New Zealand.

https://www.flexiheatuk.com/product/external-gas-boiler/

>
> It is pity that Baxi discontinued their 'HE' BBU which would have been
> something at least worth considering.
>
> The BG engineer who serviced it said the heat exchanger had a tiny leak and
> that at some stage it will fail. The trouble is I don't have any idea when.
> Unfortunately I was out at work when he came (due to BG's admin mistake) so
> did not get a chance to see where the leak was myself and ask him about it.
>
> I am not even very sure of the construction of this particular HE, from
> photos on suppliers websites and the engineering drawings on Baxi's website.
> It appears to consist of two (upper and lower) cast iron sections held
> together with bolts. I read elsewhere that some kind of gaskets may be
> involved in sealing the two sections together, and that any leaks would be
> more likely in/around the gaskets (which presumably can be replaced?) rather
> than in the the cast iron sections. I've really no idea though. I would be
> interested to know if anyone has taken one of these apart or has seen one
> close up.
>

I think the chances of it being “just a leaking gasket” are slim. You also
have the problem of extracting it, stripping it down and then potentially
finding it unrepairable and impossible to return to service leaving you
with no heating.

Tim

--
Please don't feed the trolls

Use-Author-Supplied-Address-Header@[127.1] wrote:
> I am not even very sure of the construction of this particular HE, from
> photos on suppliers websites and the engineering drawings on Baxi's website.
> It appears to consist of two (upper and lower) cast iron sections held
> together with bolts. I read elsewhere that some kind of gaskets may be
> involved in sealing the two sections together, and that any leaks would be
> more likely in/around the gaskets (which presumably can be replaced?) rather
> than in the the cast iron sections. I've really no idea though. I would be
> interested to know if anyone has taken one of these apart or has seen one
> close up.

I don't really want to encourage throwing good money after bad, but I do
note that, before it was condemned due to corrosion, our old (circa 2000)
oil boiler had seen prior welding to the flue baffles (which are I think a
crude heat exchanger). It seems it is possible to weld cast iron:

https://www.twi-global.com/technical-knowledge/faqs/can-you-weld-cast-iron

and perhaps that would be a route to repair the heat exchanger. The oil
boiler engineer who serviced didn't seem to think this kind of welding
repair was out of the ordinary, so perhaps people who maintain oil boilers
know how to do it.

Although if it's corroded then you may find the current leak is the tip of
the iceberg...

Theo

On Tuesday 12 December 2023 at 03:17:40 UTC, Use-Author-Suppli...@127.1 wrote:
> Theo <theom...@chiark.greenend.org.uk> wrote:
> : Fredxx <fre...@spam.invalid> wrote:
> : > By way of example the 248436 is a 26 fin heat exchanger and new will
> : > cost ?5-600.
> : >
> : > While it is admirable to effect a repair, the economics of running an
> : > old boiler, plus the cost of this part assuming you can get it, makes it
> : > a no-brainer to upgrade to a more modern boiler.
>
> : I would agree, although the one we had was located in the chimney breast in
> : the living room. Installing a regular boiler would have meant moving it (to
> : an outside wall, likely in the kitchen), re-piping the heating and gas to
> : get there, and then doing something with the gaping hole in the fireplace.
> : (potentially adding a gas fire if you used that function)
>
> : That's a lot more work than just replacing a heat exchanger.
>
> : Another thought would be, if you're going to have to relocate the boiler
> : anyway, it might be worth looking at a heat pump. It might be say 2x
> : disruption compared to moving the boiler, but the unit can go outside which
> : might give you more options compared with a boiler that needs to be inside.
>
> : I agree with not throwing good money after bad though. If I were the OP,
> : since the boiler is still working, I'd probably be planning my next move -
> : which would likely mean something more substantial than trying to source a
> : heat exchanger to keep the old girl staggering along.
> My thanks to everyone who followed-up. There were some useful pointers.
>
> I'll check out
> https://boilerrecycling.co.uk/product-category/heat-exchangers?filter_brand=baxi
> soon.
>
> My main problem with a wall mounted condensing boiler is that there is
> nowhere it could be installed without significantly spoiling the room it
> would have to go in, probably the kitchen. As you suggest there is a lot
> more work, plumbing involved. The built-in obsolescence of modern boilers
> also irritates me. Our current one must be about 50 years old. No modern
> condensing one is going to even get close to that!
>
> It is pity that Baxi discontinued their 'HE' BBU which would have been
> something at least worth considering.
>
> The BG engineer who serviced it said the heat exchanger had a tiny leak and
> that at some stage it will fail. The trouble is I don't have any idea when.
> Unfortunately I was out at work when he came (due to BG's admin mistake) so
> did not get a chance to see where the leak was myself and ask him about it.
>
> I am not even very sure of the construction of this particular HE, from
> photos on suppliers websites and the engineering drawings on Baxi's website.
> It appears to consist of two (upper and lower) cast iron sections held
> together with bolts. I read elsewhere that some kind of gaskets may be
> involved in sealing the two sections together, and that any leaks would be
> more likely in/around the gaskets (which presumably can be replaced?) rather
> than in the the cast iron sections. I've really no idea though. I would be
> interested to know if anyone has taken one of these apart or has seen one
> close up.
>
> Cheers
> Tom
>
> : Theo

So in summary you've no idea whether you need a new HX. Find out if it leaks, and if it does tell us its construction. Leaks are fixable many ways.

On Monday 11 December 2023 at 11:29:41 UTC, Theo wrote:
> > ...a no-brainer to upgrade to a more modern boiler.
> I would agree, although the one we had was located in the chimney breast in
> the living room. Installing a regular boiler would have meant moving it (to
> an outside wall, likely in the kitchen), re-piping the heating and gas to
> get there, and then doing something with the gaping hole in the fireplace.
> (potentially adding a gas fire if you used that function)
> That's a lot more work than just replacing a heat exchanger.

My mum had hers in the airing cupboard, flue up through the roof, and condensate drain under the floorboards to ourside.

A lot of chimneybreasts are also on the outside walls too.

Owain

On 12/12/2023 22:03, Animal wrote:
> On Tuesday 12 December 2023 at 03:17:40 UTC, Use-Author-Suppli...@127.1 wrote:
>> Theo <theom...@chiark.greenend.org.uk> wrote:
>> : Fredxx <fre...@spam.invalid> wrote:
>> : > By way of example the 248436 is a 26 fin heat exchanger and new will
>> : > cost ?5-600.
>> : >
>> : > While it is admirable to effect a repair, the economics of running an
>> : > old boiler, plus the cost of this part assuming you can get it, makes it
>> : > a no-brainer to upgrade to a more modern boiler.
>>
>> : I would agree, although the one we had was located in the chimney breast in
>> : the living room. Installing a regular boiler would have meant moving it (to
>> : an outside wall, likely in the kitchen), re-piping the heating and gas to
>> : get there, and then doing something with the gaping hole in the fireplace.
>> : (potentially adding a gas fire if you used that function)
>>
>> : That's a lot more work than just replacing a heat exchanger.
>>
>> : Another thought would be, if you're going to have to relocate the boiler
>> : anyway, it might be worth looking at a heat pump. It might be say 2x
>> : disruption compared to moving the boiler, but the unit can go outside which
>> : might give you more options compared with a boiler that needs to be inside.
>>
>> : I agree with not throwing good money after bad though. If I were the OP,
>> : since the boiler is still working, I'd probably be planning my next move -
>> : which would likely mean something more substantial than trying to source a
>> : heat exchanger to keep the old girl staggering along.
>> My thanks to everyone who followed-up. There were some useful pointers.
>>
>> I'll check out
>> https://boilerrecycling.co.uk/product-category/heat-exchangers?filter_brand=baxi
>> soon.
>>
>> My main problem with a wall mounted condensing boiler is that there is
>> nowhere it could be installed without significantly spoiling the room it
>> would have to go in, probably the kitchen. As you suggest there is a lot
>> more work, plumbing involved. The built-in obsolescence of modern boilers
>> also irritates me. Our current one must be about 50 years old. No modern
>> condensing one is going to even get close to that!
>>
>> It is pity that Baxi discontinued their 'HE' BBU which would have been
>> something at least worth considering.
>>
>> The BG engineer who serviced it said the heat exchanger had a tiny leak and
>> that at some stage it will fail. The trouble is I don't have any idea when.
>> Unfortunately I was out at work when he came (due to BG's admin mistake) so
>> did not get a chance to see where the leak was myself and ask him about it.
>>
>> I am not even very sure of the construction of this particular HE, from
>> photos on suppliers websites and the engineering drawings on Baxi's website.
>> It appears to consist of two (upper and lower) cast iron sections held
>> together with bolts. I read elsewhere that some kind of gaskets may be
>> involved in sealing the two sections together, and that any leaks would be
>> more likely in/around the gaskets (which presumably can be replaced?) rather
>> than in the the cast iron sections. I've really no idea though. I would be
>> interested to know if anyone has taken one of these apart or has seen one
>> close up.
>>
>> Cheers
>> Tom
>>
>> : Theo
>
> So in summary you've no idea whether you need a new HX. Find out if it leaks, and if it does tell us its construction. Leaks are fixable many ways.

You are going to struggle with this. You say its in good condition, yet
if its deteriorated enough for a leak in the heat exchanger, it isn't.

Whilst these things can be repaired, won't you need to find a GasSafe
registered fitter to do the work? I am not sure any one would want to do
this and certify it as "safe" ...

Dave

Theo wrote:

> I don't really want to encourage throwing good money after bad, but I do
> note that, before it was condemned due to corrosion, our old (circa 2000)
> oil boiler had seen prior welding to the flue baffles (which are I think a
> crude heat exchanger). It seems it is possible to weld cast iron:

Brazing more common?

On 13/12/2023 00:10, Andy Burns wrote:
> Theo wrote:
>
>> I don't really want to encourage throwing good money after bad, but I do
>> note that, before it was condemned due to corrosion, our old (circa 2000)
>> oil boiler had seen prior welding to the flue baffles (which are I
>> think a
>> crude heat exchanger).  It seems it is possible to weld cast iron:
>
> Brazing more common?
>
depends on strength and temperatures required. Brazing's ok for boiling
water, but hot flue gases? Not so sure.

--
"Anyone who believes that the laws of physics are mere social
conventions is invited to try transgressing those conventions from the
windows of my apartment. (I live on the twenty-first floor.) "

Alan Sokal

The Natural Philosopher wrote:

> Andy Burns wrote:
>
>> Theo wrote:
>>
>>> It seems it is possible to weld cast iron:
>>
>> Brazing more common?
>
> depends on strength and temperatures required. Brazing's ok for boiling
> water, but hot flue gases? Not so sure.

Maybe not, seems to require cherry red heat to do the brazing, I doubt a
back boiler gets that hot unless it's boiled dry? The old coke-burning
pot-belly stoves at school did.

The other technique I've seen is stitch-welding, probably good for
repairing mechanical strength, but maybe also unsuitable if it needs to
be gas tight?

On Tuesday, December 12, 2023 at 9:45:52 AM UTC, Tim+ wrote:
> <Use-Author-Supplied-Address-Header@[127.1]> wrote:
> > Theo <theom...@chiark.greenend.org.uk> wrote:
> >> Fredxx <fre...@spam.invalid> wrote:
> >>> By way of example the 248436 is a 26 fin heat exchanger and new will
> >>> cost ?5-600.
> >>>
> >>> While it is admirable to effect a repair, the economics of running an
> >>> old boiler, plus the cost of this part assuming you can get it, makes it
> >>> a no-brainer to upgrade to a more modern boiler.
> >
> >> I would agree, although the one we had was located in the chimney breast in
> >> the living room. Installing a regular boiler would have meant moving it (to
> >> an outside wall, likely in the kitchen), re-piping the heating and gas to
> >> get there, and then doing something with the gaping hole in the fireplace.
> >> (potentially adding a gas fire if you used that function)
> >
> >> That's a lot more work than just replacing a heat exchanger.
> >
> >> Another thought would be, if you're going to have to relocate the boiler
> >> anyway, it might be worth looking at a heat pump. It might be say 2x
> >> disruption compared to moving the boiler, but the unit can go outside which
> >> might give you more options compared with a boiler that needs to be inside.
> >
> >> I agree with not throwing good money after bad though. If I were the OP,
> >> since the boiler is still working, I'd probably be planning my next move -
> >> which would likely mean something more substantial than trying to source a
> >> heat exchanger to keep the old girl staggering along.
> >
> > My thanks to everyone who followed-up. There were some useful pointers.
> >
> > I'll check out
> > https://boilerrecycling.co.uk/product-category/heat-exchangers?filter_brand=baxi
> > soon.
> >
> > My main problem with a wall mounted condensing boiler is that there is
> > nowhere it could be installed without significantly spoiling the room it
> > would have to go in, probably the kitchen. As you suggest there is a lot
> > more work, plumbing involved. The built-in obsolescence of modern boilers
> > also irritates me. Our current one must be about 50 years old. No modern
> > condensing one is going to even get close to that!
> Maybe outside mounting is worth considering? Relatively rare for gas
> boilers here but it seemed to be he normally in New Zealand.
>
> https://www.flexiheatuk.com/product/external-gas-boiler/

Interesting ... I am in a similar position to the OP, and am wondering about the
route to take when our back boiler dies. Has anyone here experience of
fitting/using an outside-mounted boiler? (I am thinking of a system boiler rather
than a combi, FWIW)

Thanks, J^n

On 13/12/2023 09:06, jkn wrote:
> Interesting ... I am in a similar position to the OP, and am wondering about the
> route to take when our back boiler dies. Has anyone here experience of
> fitting/using an outside-mounted boiler? (I am thinking of a system boiler rather
> than a combi, FWIW)

One house I was in had an externally mounted (system) oil boiler. It
was green and Irish. :-)(

I think it was a Grant boiler.. Worked bloody well to be honest.

A friend has a standard system boiler in what amounts to an outside
cupboard, with a frost stat, that works OK too.

Personally if you have the space, its probably a good idea,.

--
Renewable energy: Expensive solutions that don't work to a problem that
doesn't exist instituted by self legalising protection rackets that
don't protect, masquerading as public servants who don't serve the public.

On 12 Dec 2023 at 09:45:47 GMT, Tim+ wrote:

> Maybe outside mounting is worth considering? Relatively rare for gas
> boilers here but it seemed to be he normally in New Zealand.
>
> https://www.flexiheatuk.com/product/external-gas-boiler/

Or a heat pump - £7500 grant available right now . . .
--
Cheers, Rob, Sheffield UK

On 13/12/2023 15:35, RJH wrote:
> On 12 Dec 2023 at 09:45:47 GMT, Tim+ wrote:
>
>> Maybe outside mounting is worth considering? Relatively rare for gas
>> boilers here but it seemed to be he normally in New Zealand.
>>
>> https://www.flexiheatuk.com/product/external-gas-boiler/
>
> Or a heat pump - £7500 grant available right now . . .

Doan make me larf..

--
“But what a weak barrier is truth when it stands in the way of an
hypothesis!”

Mary Wollstonecraft

On 13/12/2023 15:35, RJH wrote:
> On 12 Dec 2023 at 09:45:47 GMT, Tim+ wrote:
>
>> Maybe outside mounting is worth considering? Relatively rare for gas
>> boilers here but it seemed to be he normally in New Zealand.
>>
>> https://www.flexiheatuk.com/product/external-gas-boiler/
>
> Or a heat pump - £7500 grant available right now . . .

If the system is that old the CH is probably designed for a very high
flow temperature. £7500 may not make too much of a dent in the cost of
modifying the rest of the system:)

--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk