back boiler combined with oil boiler minus the hot water cylinder?

tom1ie

Can you combine a stove back boiler system with an oil boiler system to heat radiators only? The hot water is on a seperate solar system. Just wondering can the back boiler on the stove be combined with an oil condensing boiler also. (have my doubts, cause i think the condensing oil boiler would be pressurized, is this correct?) Any help appreciated!

heinbloed

There are different oil condensing boilers available, some pressurised, others 'vented', operating on low pressure.

In principle you can have as many thermal sources in one line as you want. As long as the critical parameters are met (pressure, temperature, flow rate and corrosion protection) there is no problem with this.

If combining differing pressures (open and vented systems) you can use heat exchangers between them.

Contact a heating engineer or similar to prepare a thermal demand calculation. Otherwise the system might become oversized and uneconomical.

tom1ie

heinbloed wrote: »

There are different oil condensing boilers available, some pressurised, others 'vented', operating on low pressure.

In principle you can have as many thermal sources in one line as you want. As long as the critical parameters are met (pressure, temperature, flow rate and corrosion protection) there is no problem with this.

If combining differing pressures (open and vented systems) you can use heat exchangers between them.

Contact a heating engineer or similar to prepare a thermal demand calculation. Otherwise the system might become oversized and uneconomical.

Thanks for the quick reply heinbloed. Can you recomend a good heating contractor or even point me in the right direction for contacting one?

heinbloed

No, check the yellow/golden pages.
Ask for a written calculation on the project's thermal energy demand according to EN12831. If they can't provide you with it (signed and sealed) then they are not good.

tom1ie

heinbloed wrote: »

No, check the yellow/golden pages.
Ask for a written calculation on the project's thermal energy demand according to EN12831. If they can't provide you with it (signed and sealed) then they are not good.

Great! will do thanks.:)

xocal

For what it's worth, I combined an oil fired system with a Parkray back boiler back in the late 60's and have never had a problem and it's still going strong.
However I was advised at the time by experts that it couldn't be done.
Mind you I have a hot water cylinder in the system, and have the circulating pump regulated by a thermostat attached to the return pipe high up in the system, and not by the boiler thermostat!
This means that the pump keeps circulating until the water drops to a preset temperature, unlike the modern tendancy to have it switch off when the burner stops!
I find that this allows me to have better control and use of the heated water, as I use a time switch to switch the burner on and off.

heinbloed

Xocal wrote:

Mind you I have a hot water cylinder in the system, and have the circulating pump regulated by a thermostat attached to the return pipe high up in the system, and not by the boiler thermostat!
This means that the pump keeps circulating until the water drops to a preset temperature, unlike the modern tendancy to have it switch off when the burner stops!

There are nowadays intelligent pumps available, these sense the temperature and increase or decrease the flow rate. They are modulating according to the temperature. Some of these intelligent pumps are modulating according to the pressure, some modulate to both parameters, temperature and pressure. This does away with a seperate temperature or pressure sensor.
Just in case you need a new pump, check out if these new types of pumps might be suitable. They are electric energy saving as well, 'A' - rated or 'A+' - rated.

andy2die4

xocal wrote: »

I have a hot water cylinder in the system, and have the circulating pump regulated by a thermostat attached to the return pipe high up in the system, and not by the boiler thermostat!
This means that the pump keeps circulating until the water drops to a preset temperature, unlike the modern tendancy to have it switch off when the burner stops!

There's no school like old school. There were no fancy gismos, interweb or qualpex in the 60's only plumbers who were taught how a system really worked.

sullzz

andy2die4 wrote: »

There's no school like old school. There were no fancy gismos, interweb or qualpex in the 60's only plumbers who were taught how a system really worked.

Yes but why does new technology sell , because its more efficient , why is qualpex used, because there is no need to notch joists , preventing pipes being burst in the future when lifting boards or causing noises when copper fitted poorly , fair enough the tradesmen were good but we have to move with the times

gifted

sullzz wrote: »

Yes but why does new technology sell , because its more efficient , why is qualpex used, because there is no need to notch joists , preventing pipes being burst in the future when lifting boards or causing noises when copper fitted poorly , fair enough the tradesmen were good but we have to move with the times

Qualpex has decaffenated the trade of plumbing, there is an awful lot of apprentices coming out of their "apprenticeship" with just experience of qualpex, no copper bending, no brazing, no gas welding, no pipe fitting experience with Gun Barrel.(apart from their time in FAS) I taught in FAS as a plumbing instructor for a few years and the amount of times that an apprentice told me that they only work on "plastic" was sad. Qualpex wasn't invented so joists could be drilled, it was invented for the same reason as everything else..it's faster to work with! Any monkey can drill a hole in a joist and pull some qualpex through it... I hate the stuff.

sullzz

gifted wrote: »

Qualpex has decaffenated the trade of plumbing, there is an awful lot of apprentices coming out of their "apprenticeship" with just experience of qualpex, no copper bending, no brazing, no gas welding, no pipe fitting experience with Gun Barrel.(apart from their time in FAS) I taught in FAS as a plumbing instructor for a few years and the amount of times that an apprentice told me that they only work on "plastic" was sad. Qualpex wasn't invented so joists could be drilled, it was invented for the same reason as everything else..it's faster to work with! Any monkey can drill a hole in a joist and pull some qualpex through it... I hate the stuff.

Qualpex is great when used correctly in the right situation , i hate seeing qualpex on surface , your right when you say any monkey can drill a joist and pull it through , but it makes a better job . Not every apprentice can have the opportunity to work on jobs where he/she can gas weld or braze or even cut and thread pipe , its unfortunate but its how it is , some companys just stick to domestic . A lot of bad apprentices got through the system in the last few years either from" house bashing sites" or from being on the larger industrial sites just hanging brackets or unistrut , they never had a chance and its not only the employers fault its also down to fas for letting them through the system, i know one lad personally who has his papers and i wouldnt put him to the standards if a first year apprentice , i think fas should have inspectors visiting apprentices on the job to inspect their on the job training standards

Lex Luthor

sorry for jumping in here, but I am interested in the possibility of a back boiler.

Currently have an solid fuel open fire and oil central heating. Is it possible to get a back boiler installed to heat the rads and/or hot water cylinder when the fire is lit and use the oil c/h when I wish?

There is a rad not too far away from the fireplace so if it was required to tap into the nearest rad, I wouldnt see it as a massive run of pipework (maybe 6ft from fireplace)

Would it mean replacing my cast iron fireplace for something suited to the back boiler aswell?

Any opinions welcome.

gifted

sullzz wrote: »

Qualpex is great when used correctly in the right situation , i hate seeing qualpex on surface , your right when you say any monkey can drill a joist and pull it through , but it makes a better job . Not every apprentice can have the opportunity to work on jobs where he/she can gas weld or braze or even cut and thread pipe , its unfortunate but its how it is , some companys just stick to domestic . A lot of bad apprentices got through the system in the last few years either from" house bashing sites" or from being on the larger industrial sites just hanging brackets or unistrut , they never had a chance and its not only the employers fault its also down to fas for letting them through the system, i know one lad personally who has his papers and i wouldnt put him to the standards if a first year apprentice , i think fas should have inspectors visiting apprentices on the job to inspect their on the job training standards

Completely agree with you, I worked with a 3rd year apprentice for a large mech contractor and he did not know the difference between a 310 and a 311...While out in FAS i used get phone calls off apprentices employers asking me to pass their apprentices who I failed, had one second year apprentice who didn't know how to pipe up a hot water cylinder, 3 times he attempted his exam and 3 times he failed, his boss rang me pleading with me to change his result even though he could probably blow up a house with the way he wanted to pipe it.

DoneDL

Any solid fuel appliance with a back boiler should be connected to a cylinder with its own coil. In theory you can pipe a solid fuel appliance any way you like but you will be going against building regs and most certainly against the manufacturers instructions. It can be done as a DIY project because you will bear the consequences if it goes wrong but no professional would do it.

heinbloed

DoneDL wrote:

Any solid fuel appliance with a back boiler should be connected to a cylinder with its own coil. In theory you can pipe a solid fuel appliance any way you like but you will be going against building regs .......

It is simply not true that such an installation is against building regulations. I have the Irish building regulations in front and nothing the like is mentioned there.

Most EU continental solid fuel boilers ( and Irish solid fuel boilers as well) do work directly, not via a secondary heat exchanger (

connected to a cylinder with its own coil

).
Some of these boilers are listed in the SEAI list for subsidies. The manufacturers of these solid fuel boilers do NOT recommend the installation of secondary heat exchangers.
Be it pellet boilers, log boilers, gasification boilers or coal or wood chip boilers.

What DoneL has stated in his post is bare of any thruth.

@ DoneDL: publish a link to these obscure building regulations please.

DoneDL

Heating and Domestic Hot Water Systems for dwellings – Achieving compliance with Part L 2008, knock yourself out, then have a look at the relevant BS documents. Then wander over to HETAS and then show a gravity solid fuel boiler manufacturer that has ever given a blessing that allows connecting directly to a heating system with no thought about the use of a heat leak or cylinder.

esox28

heinbloed wrote: »

No, check the yellow/golden pages.
Ask for a written calculation on the project's thermal energy demand according to EN12831. If they can't provide you with it (signed and sealed) then they are not good.

yea the golden pages will have a very short list of solid fuel installers that could or even want to 'sign and seal' such a doc.

I'm not sure why the irish regs arent detailing the correct installation of solid fuel stove's and ranges.

of course you dont have to install a gravity piped circuit connected to a suitable hot water storage cylinder if you want to, but has any one here ever seen it go wrong, the whole system relies on electrical and mechanical means of disapating the heat generated.

bare in mind a general solid fuel fire burns a approx 500 * c water boils @ 100* c and steam expands @ 1600 x the volume of water

because I for one wouldent want to be even living next door to a system heinbloed says is common place in the Eu.

kscobie

The simple answer to the first question is no.

heinbloed

There is nothing like it in the Irish building regulations, DonDL.
Nothing.

You better read them.


@the OP:

Check the SEAI list for the registered solid fuel boilers and then contact these manufacturers via their home pages, they have the technical details and installer manuals published. What you have in mind is the recommended practice.

Some self-stiled plumbers here in the forum frequently come up with terms like " it's against building regulations " but obviously have never read these building regulations.

heinbloed

Esox woders:

I'm not sure why the irish regs arent detailing the correct installation of solid fuel stove's and ranges.

Maybe the authorities can't imagine how stupid some in the trade are?

No one on the EU continent would install a household solid fuel boiler with a secondary heatexchanger. That would then be against min. efficiency legislations, each heatexchanger involved in thermal transmissions costs at least (!!) 5% of fuel efficiency.

tom1ie

ok, glad we got this argument going cause this is what i really need to find out:D.
The whole idea is to be able to walk into the house on a cold day, start the heating with the touch of a button via the oil or gas boiler (without heating the hot water tank as ive 100% hot water via solar), whilst its getting hot, light a fire in the stove, let the stove take over heating the rads after ten twenty mins or so and then turn off the oil/gas boiler saving me €!!
Incidentally, what boiler would you guys recomend, as i dont want to heat the water in the hot tank just in the rads? combi? I have oil at the moment as i think ive already stated. Any help welcome:p

DoneDL

heinbloed,

Heating and Domestic Hot Water Systems for dwellings – Achieving compliance with Part L 2008

Part L of the Building Regulations is concerned with the conservation of fuel and energy in dwellings. Part L for dwellings, is supported by a Technical Guidance Document (TGD) L Dwellings 2008 which gives guidance on how to satisfy the energy performance provisions of the Building Regulations for new and existing dwellings.
The TGD quotes the regulatory requirements where relevant for the sake of completeness. These provisions are distinguished in the text by a grey background. In cases of doubt, however, it may be necessary to refer directly to the Building Regulations as amended.
The TGD was published in 2008 in support of the amendments to the Building Regulations, Statutory Instruments No. 854 of 2007. The amendment came into force on 1 July 2008.

Why would you think this document was not part of the building regulations.

heinbloed

DoneDL asks:

" Heating and Domestic Hot Water Systems for dwellings – Achieving compliance with Part L 2008

Part L of the Building Regulations is concerned with the conservation of fuel and energy in dwellings. Part L for dwellings, is supported by a Technical Guidance Document (TGD) L Dwellings 2008 which gives guidance on how to satisfy the energy performance provisions of the Building Regulations for new and existing dwellings.
The TGD quotes the regulatory requirements where relevant for the sake of completeness. These provisions are distinguished in the text by a grey background. In cases of doubt, however, it may be necessary to refer directly to the Building Regulations as amended.
The TGD was published in 2008 in support of the amendments to the Building Regulations, Statutory Instruments No. 854 of 2007. The amendment came into force on 1 July 2008.

Why would you think this document was not part of the building regulations.

" Question mark .....

Because a guideline is a guideline. A guideline is not a building regulation.
In case you have the guidelines in their written form together with the technical guideline : the grey part (the part with the grey background) is the building regulation.

The guidelines are for the blind, for the those who do not understand the building regulations.


Now a question from me:
Why do you think the Irish building regulations would tell the installer anything about how to install a safe and efficient CH system?
It says specially in your quote:

These provisions are distinguished in the text by a grey background. In cases of doubt, however, it may be necessary to refer directly to the Building Regulations as amended.

So please refer to the building regulations when telling us or the OP where it says that he or his competent installer is not allowed to install a solid fuel boiler directly integrated into a CH system - as it is usus with the very fast majority of all installed CH solid fuel boilers.

There is nothing the like in the building regulations. As you can see.

heinbloed

@ tom1ie:

Contact a heating engineer. There are several things to be looked at when deciding on a new boiler, first of all the building regulations.
These demand for example a boiler efficiency of over 90%.
And a boiler should not be oversized, so an energy demand calculation is necessary.

DoneDL

heinbloed, I don`t think you have spent much time with any regulation. The SI or act will have definitions and scope, it will be supported by documents that are statutory and do not require the support documents to be passed by the Dail. The regulations are supported by the act and state minimum requirements.

So please refer to the building regulations when telling us or the OP where it says that he or his competent installer is not allowed to install a solid fuel boiler directly integrated into a CH system - as it is usus with the very fast majority of all installed CH solid fuel boilers.

Table 18 Minimum provisions for system circulation, fuel storage, hot water storage, system preparation and commissioning of solid fuel central heating
Minimum provision for new systems
Minimum provision for replacement systems
Supplementary information
a. System circulation
a. Where boiler interlock is available, fully pumped circulation should be chosen
b. The manufacturer’s instructions on the sizing and positioning of heat leak radiators should be followed
c. Solid-fuel appliances should not be fitted to sealed heating systems with expansion vessels, except where specifically permitted by the manufacturer

esox28

each heatexchanger involved in thermal transmissions costs at least (!!) 5% of fuel efficiency.

of course is does...!

the ch solid fuel stove can be installed in such a way as to by-pass the hotwater cylinder when the circulating pump is operating from a pipe stat thus delivering nearly all ch heated water gerenated by the stove.

But make no mistake you do need to create a heat leak by non-mechanical means, a gravity piped circuit connected to a hotwater cylinder is the preferred method, but a suitably large ch radiator can be used instead of cylinder coil.

esox28

heinbloed wrote: »

@ tom1ie:

Contact a heating engineer. There are several things to be looked at when deciding on a new boiler, first of all the building regulations.
These demand for example a boiler efficiency of over 90%.
And a boiler should not be oversized, so an energy demand calculation is necessary.

there are no solid fuel stoves burning wood, peat and coal running at < 90% efficiency, or have stanley come up with a condencing soild fuel eirn stove:rolleyes::rolleyes:

Micky Dolenz

gifted wrote: »

Qualpex has decaffenated the trade of plumbing, there is an awful lot of apprentices coming out of their "apprenticeship" with just experience of qualpex, no copper bending, no brazing, no gas welding, no pipe fitting experience with Gun Barrel.(apart from their time in FAS) I taught in FAS as a plumbing instructor for a few years and the amount of times that an apprentice told me that they only work on "plastic" was sad. Qualpex wasn't invented so joists could be drilled, it was invented for the same reason as everything else..it's faster to work with! Any monkey can drill a hole in a joist and pull some qualpex through it... I hate the stuff.

Just like any monkey can pull a cable through a joist, it takes a special kind of monkey to tie it all together though :P

How could you possibly hate qualpex?. Faster to work with, cheaper and more durable then copper, it will never corrode, stands up to extreme cold better then a metal pipe. I could go on.

I'm not exactly old school, or new for that matter. But polyethylene pipe has a welcome place in the industry today.

DoneDL

Micky Dolenz wrote: »

I'm not exactly old school, or new for that matter. But polyethylene pipe has a welcome place in the industry today.

You wouldn`t be taking the proverbial out of those of us who are?

Micky Dolenz

DoneDL wrote: »

You wouldn`t be taking the proverbial out of those of us who are?

Nope. Served my time under a guy who insisted we drag big oxyacetylene bottles after us. Bending copper in attics and piping houses on a sub floor, cross over's, cross unders, all copper and all brazed.

Did more then my share of gas welding when we were working on GB systems.And Stood many a long day at a pipe bench threading glav pipe by hand.

More then once having to drain down an entire system because a brazed joint weeped.

I can't fault polyethylene pipe if used in the right manner. My apprentices won't learn the things I did when I served my time, just like I didn't learn the things they learn now.

Embrace change or be left behind.

DoneDL

Just kidding Micky, nothing wrong with either school in truth.

heinbloed

Esox28 wrote:

Quote:
Originally Posted by heinbloed
@ tom1ie:

Contact a heating engineer. There are several things to be looked at when deciding on a new boiler, first of all the building regulations.
These demand for example a boiler efficiency of over 90%.
And a boiler should not be oversized, so an energy demand calculation is necessary.

there are no solid fuel stoves burning wood, peat and coal running at < 90% efficiency, or have stanley come up with a condencing soild fuel eirn stove

If quoting quote correct, Esox28. A text as mine which you have quoted relates to a context, the question of tom1ie.
No one has said that there is a solid fuel boiler with an efficiency of over 90% to be connected.
Read.

heinbloed

DoneDL wrote a post which doesn't make any sense to the discussion nor to the Ops question. No quoting marks, no text sources, no plausible references, no grammar etc..:

heinbloed, I don`t think you have spent much time with any regulation. The SI or act will have definitions and scope, it will be supported by documents that are statutory and do not require the support documents to be passed by the Dail. The regulations are supported by the act and state minimum requirements.

So please refer to the building regulations when telling us or the OP where it says that he or his competent installer is not allowed to install a solid fuel boiler directly integrated into a CH system - as it is usus with the very fast majority of all installed CH solid fuel boilers.

Table 18 Minimum provisions for system circulation, fuel storage, hot water storage, system preparation and commissioning of solid fuel central heating
Minimum provision for new systems
Minimum provision for replacement systems
Supplementary information
a. System circulation
a. Where boiler interlock is available, fully pumped circulation should be chosen
b. The manufacturer’s instructions on the sizing and positioning of heat leak radiators should be followed
c. Solid-fuel appliances should not be fitted to sealed heating systems with expansion vessels, except where specifically permitted by the manufacturer

It is beyond my intellectual capacity to understand the meaning of this posting.

gifted

Micky Dolenz wrote: »

Nope. Served my time under a guy who insisted we drag big oxyacetylene bottles after us. Bending copper in attics and piping houses on a sub floor, cross over's, cross unders, all copper and all brazed.

Did more then my share of gas welding when we were working on GB systems.And Stood many a long day at a pipe bench threading glav pipe by hand.

More then once having to drain down an entire system because a brazed joint weeped.

I can't fault polyethylene pipe if used in the right manner. My apprentices won't learn the things I did when I served my time, just like I didn't learn the things they learn now.

Embrace change or be left behind.

Each to their own , I wasted too many hours and long evenings trying to repair qualpex pipe that slipped out of compression fittings . Heard too many apprentices tell me that all they worked on was "plastic" Qualpex pipe may have its uses in domestic situations but I have yet to hear anyone say "nice qualpex" when commenting on someones work but have heard many times "nice copper bending"