On Wednesday 20 December 2023 at 17:18:39 UTC, Max Demian wrote:
> On 20/12/2023 12:38, nib wrote:
> > On Wed, 20 Dec 2023 12:16:48 +0000, Max Demian wrote:
> >
> >> On 20/12/2023 09:04, David Wade wrote:
> >>> On 20/12/2023 06:32, Animal wrote:
> >>
> >>>> Compared to gas, ASHP costs much more upfront, more per therm output,
> >>>> is noisy, takes up more space, and efficiency takes a dump when it
> >>>> gets near freezing. The increased cost per output is being hidden by
> >>>> insisting on adding insulation when installing. So yeah, it makes as
> >>>> much sense as many green measures.
> >>>>
> >>>>
> >>> I think we are wedded to the past with water in radiators to heat the
> >>> house.
> >>
> >> It's a convenient way to distribute heat around a house. An alternative
> >> would be ducted air, but this required bulky ducts and may be noisy.
> >>
> >>> I love my split AC units but I do have enough space outside for a
> >>> couple of outside units.
> >>
> >> If you have a lot of rooms it's inconvenient to have separate
> >> heating/cooling appliances unless they are resistive electric heaters
> >> which are expensive to run (as you are converting "high grade" energy
> >> (electricity) directly into "low grade" energy (heat).)
> >>
> >>> The only thing that keeps the gas cheaper is the stupid pricing for
> >>> electricity,
> >>
> >> More a matter of the Second Law of Thermodynamics and its relation to
> >> the efficiency of Heat Engines (which most power stations are).
> >
> > Partly that. Currently, my electricity per kWh is nearly 5 times gas, and
> > I'm sure power stations are more than 20% efficient!
> A factor of three is more common. (Mine is 3.6 ATM.) I think gas power
> stations are about 40% efficient; and then there are the losses in the
> power lines.

and the small matter of the costs of power stations.

On 20/12/2023 17:18, Max Demian wrote:
> A factor of three is more common. (Mine is 3.6 ATM.) I think gas power
> stations are about 40% efficient; and then there are the losses in the
> power lines.

Combined cycle gas power stations are over 60% efficient
Open cycle gas turbines scratch at 37%.
]

--
"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

On 19/12/2023 03:16, Use-Author-Supplied-Address-Header@[127.1] wrote:
> Andrew <Andrew97d@btinternet.com> wrote:
> : On 10/12/2023 21:38, Tim+ wrote:
> : > <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.
> : >
> : I slung mine in the local amenity tip metal skip 20 years ago.
> : 'Sling' needs to be qualified by 'struggled on my own' on account
> : of its significant weight.
>
> : These cast iron heat exchangers are bullet proof but what fails is
> : the bolts that hold the two halves together.
>
> : Chap across the road still has his and a few years back was also
> : looking for a possible new heat exchanger.
>
> : If the property uses class 2 flue blocks then they are more efficient
> : than believed because the wall of the bedroom above gets the extra
> : heat from these flue blocks. The houses on my estate had much smaller
> : radiators in this bedroom compared to the other bedrooms for this reason.
>
> : > 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
> : >
> : >
> : The galvanised metal casing also tends to rot away.
>
> I am curious about the internal plumbing of the HE, not having seen mine
> for reasons explained above.
>

There isnt any. I dont think it has any, apart from baffles
that are part of the original casting process. There are simply
three threaded tappings on each side so that the 28mm gravity feeds
and the 22mm pumped tapping for CH can be on either side.

Essentially it is just a cast iron box with fins on the outside
and tappings on either side for water connections, which sits
on top of the gas burners.

On 20/12/2023 17:18, Max Demian wrote:
> On 20/12/2023 12:38, nib wrote:
>> On Wed, 20 Dec 2023 12:16:48 +0000, Max Demian wrote:
>>
>>> On 20/12/2023 09:04, David Wade wrote:
>>>> On 20/12/2023 06:32, Animal wrote:
>>>
>>>>> Compared to gas, ASHP costs much more upfront, more per therm output,
>>>>> is noisy, takes up more space, and efficiency takes a dump when it
>>>>> gets near freezing. The increased cost per output is being hidden by
>>>>> insisting on adding insulation when installing. So yeah, it makes as
>>>>> much sense as many green measures.
>>>>>
>>>>>
>>>> I think we are wedded to the past with water in radiators to heat the
>>>> house.
>>>
>>> It's a convenient way to distribute heat around a house. An alternative
>>> would be ducted air, but this required bulky ducts and may be noisy.
>>>
>>>> I love my split AC units but I do have enough space outside for a
>>>> couple of outside units.
>>>
>>> If you have a lot of rooms it's inconvenient to have separate
>>> heating/cooling appliances unless they are resistive electric heaters
>>> which are expensive to run (as you are converting "high grade" energy
>>> (electricity) directly into "low grade" energy (heat).)
>>>
>>>> The only thing that keeps the gas cheaper is the stupid pricing for
>>>> electricity,
>>>
>>> More a matter of the Second Law of Thermodynamics and its relation to
>>> the efficiency of Heat Engines (which most power stations are).
>>
>> Partly that. Currently, my electricity per kWh is nearly 5 times gas, and
>> I'm sure power stations are more than 20% efficient!
>
> A factor of three is more common. (Mine is 3.6 ATM.) I think gas power
> stations are about 40% efficient; and then there are the losses in the
> power lines.
>

Which are more than most people realise. If the gas network leaked
the same proportion of gas transported there would be major problem
with fires and explosions.

On Friday 22 December 2023 at 13:54:55 UTC, Andrew wrote:
> On 19/12/2023 03:16, Use-Author-Supplied-Address-Header@[127.1] wrote:
> > Andrew <Andr...@btinternet.com> wrote:
> > : On 10/12/2023 21:38, Tim+ wrote:
> > : > <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.
> > : >
> > : I slung mine in the local amenity tip metal skip 20 years ago.
> > : 'Sling' needs to be qualified by 'struggled on my own' on account
> > : of its significant weight.
> >
> > : These cast iron heat exchangers are bullet proof but what fails is
> > : the bolts that hold the two halves together.
> >
> > : Chap across the road still has his and a few years back was also
> > : looking for a possible new heat exchanger.
> >
> > : If the property uses class 2 flue blocks then they are more efficient
> > : than believed because the wall of the bedroom above gets the extra
> > : heat from these flue blocks. The houses on my estate had much smaller
> > : radiators in this bedroom compared to the other bedrooms for this reason.
> >
> > : > 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
> > : >
> > : >
> > : The galvanised metal casing also tends to rot away.
> >
> > I am curious about the internal plumbing of the HE, not having seen mine
> > for reasons explained above.
> >
> There isnt any. I dont think it has any, apart from baffles
> that are part of the original casting process. There are simply
> three threaded tappings on each side so that the 28mm gravity feeds
> and the 22mm pumped tapping for CH can be on either side.
>
> Essentially it is just a cast iron box with fins on the outside
> and tappings on either side for water connections, which sits
> on top of the gas burners.

shouldn't be too hard to copy, either in welded steel sheet or re-cast using the original as the posiitive