Is it possible to fit a back boiler to an existing fire back?

babygirlz

We already have a solid fuel fire but I want to fit a back boiler as I'd like to get a stove fitted and I'd like it to heat the rads.
Is it possible to fit a bb? The house is 8 years old, 2 storey and timber frame.
Thanks.

demanufactured

If your fitting a stove then you need to get a boiler stove.
They have the back boiler in them already

babygirlz

demanufactured wrote: »

If your fitting a stove then you need to get a boiler stove.
They have the back boiler in them already

Yes I know that.


How difficult is it to connect it to the existing rads if there hasn't been a boiler already ?

heinbloed

How difficult is it to connect it to the existing rads if there hasn't been a boiler already

?

How are the radiators supplied with thermal energy so far - without a boiler?
Are these electric radiators, oil-filled ones?

babygirlz

heinbloed wrote: »

?

How are the radiators supplied with thermal energy so far - without a boiler?
Are these electric radiators, oil-filled ones?

Oil rads.

heinbloed

"

Quote:
Originally Posted by heinbloed
?

How are the radiators supplied with thermal energy so far - without a boiler?
Are these electric radiators, oil-filled ones?


Oil rads.

"



That's funny!

babygirlz

heinbloed wrote: »

"

Quote:
Originally Posted by heinbloed
?

How are the radiators supplied with thermal energy so far - without a boiler?
Are these electric radiators, oil-filled ones?


Oil rads.

"



That's funny!

Really?? Enlighten me as to the humorous part of my post please.

Are you an expert on heating and plumbing? If not please do not supply irrelevant information and for god sake grow up!

JohnnieK

If you are getting a boiler stove then pipes from this will have to get from this to your existing pipe work. How easy it is will depend on the setup and for that reason you should get some contractors in survey the job. It is very possible to do this project but it must be done right because if not you could end up with a very dangerous installation.

There is a stove sticky at the top of the forum and perhaps you should post in that or maybe one of the mods could move it there.

You need to be talking to stove fan or some one like him on this.

shane0007

An unrestricted rising flow will also be required to the hw cylinder and the cylinder will have to changed to a dual/twin coil cylinder.

anthonyos

heinbloed wrote: »

?

How are the radiators supplied with thermal energy so far - without a boiler?
Are these electric radiators, oil-filled ones?

heinbloed your full of crap can you not keep it simple for the op:o

demanufactured

anthonyos wrote: »

heinbloed your full of crap can you not keep it simple for the op:o

Meow

gifted

shane0007 wrote: »

An unrestricted rising flow will also be required to the hw cylinder and the cylinder will have to changed to a dual/twin coil cylinder.

Hiya,

Hope you don't mind me for asking but why would you change the cylinder to a dual coil?

shane0007

gifted wrote: »

shane0007 wrote: »

An unrestricted rising flow will also be required to the hw cylinder and the cylinder will have to changed to a dual/twin coil cylinder.

Hiya,

Hope you don't mind me for asking but why would you change the cylinder to a dual coil?

If not, the back boiler will heat the oil boiler and the oil boiler will heat the stove thus losing a lot kw from the rads. The 2 must have separate circuits only sharing the radiator circuit. Non-return valves can only be fitted to the secondary circuit of the solid fuel circuit.

gifted

shane0007 wrote: »

If not, the back boiler will heat the oil boiler and the oil boiler will heat the stove thus losing a lot kw from the rads. The 2 must have separate circuits only sharing the radiator circuit. Non-return valves can only be fitted to the secondary circuit of the solid fuel circuit.

I joined up an oil boiler and a solid fuel back boiler a few years ago, put a check valve after the pump on the oil boiler and put a check valve after the pump on the solid fuel side, both on the flow pipe. Each check valve prevented the heat from the other boiler from entering thus no heat loss.I put a safety valve on the solid fuel back boiler before the pump and connected the flow and return into the oil boiler circuit. Never changed the cylinder, changed the oil sytem from pressurised to open system because of the solid fuel back boiler. Got a spark to wire up the pumps so that when the pump on the solid fuel was working it prevented the oil boiler from working so the 2 systems never ran together. Took the vent pipe up to the F & E tank from the hot water cylinder. If I wanted to be even more safe I could have put an extra expansion pipe up to the F & E tank from the spot where I put the safety valve. System works perfect still today

Plombier

I joined up an oil boiler and a solid fuel back boiler a few years ago, put a check valve after the pump on the oil boiler and put a check valve after the pump on the solid fuel side, both on the flow pipe. Each check valve prevented the heat from the other boiler from entering thus no heat loss.I put a safety valve on the solid fuel back boiler before the pump and connected the flow and return into the oil boiler circuit. Never changed the cylinder, changed the oil sytem from pressurised to open system because of the solid fuel back boiler. Got a spark to wire up the pumps so that when the pump on the solid fuel was working it prevented the oil boiler from working so the 2 systems never ran together. Took the vent pipe up to the F & E tank from the hot water cylinder. If I wanted to be even more safe I could have put an extra expansion pipe up to the F & E tank from the spot where I put the safety valve. System works perfect still today

This does not mean you did it correctly, it just means you didn't know what you were doing.

gifted

What did I do wrong?

shane0007

gifted wrote: »

What did I do wrong?

Everything!
What happens if you have a fire lit to heat the parish and there is a power cut or pump failure?
You must have no restrictions on the primary circuit of solid fuel and that includes a circulating pump and most of all a non-return valve!
Your oil boiler will still heat your back boiler and vice versa as it will follow the same route. It is flowing the same direction for each source through the coil so a non-return valve is useless.

gifted

shane0007 wrote: »

Everything!
What happens if you have a fire lit to heat the parish and there is a power cut or pump failure?
You must have no restrictions on the primary circuit of solid fuel and that includes a circulating pump and most of all a non-return valve!
Your oil boiler will still heat your back boiler and vice versa as it will follow the same route. It is flowing the same direction for each source through the coil so a non-return valve is useless.

Nearly every house in Ireland had a solid fuel back boiler for central heating with circulating pumps fitted..long before gas and oil boilers became readily available.

What happens if you just have a solid fuel back boiler and there is a power cut? ...pump fails...water expands up through Flow pipe, through the pump (restriction)...Oftec regs state that if a valve must be used of a Feed and Expansion pipe then it must be the type that cannot be interfered with,so I used a flap type non return valve hence the reason why we fit a lockshied valve on the return pipe going into an expansion vessel on a heating system, I also said that I fitted a safety valve before the pump and check valve...

The water flowing from the oil boiler through the flow pipe cannot go through the back boiler as the check valve will stop it, it will go through the coil in the DHW cylinder and return through the return pipe to the oil boiler and vica versa with the solid fuel...

Draw out a schematic and you will see...back boiler to one side...take flow and return straight off and into the coil in the cylinder..draw in the pump and the check valve on the solid fuel...now draw oil boiler on the other side ...take flow and return from oil boiler and connect into solid fuel flow and return..draw in pump and check valve on flow pipe next to oil boiler.. now draw in a few rads on both circuits,....now follow the flow of water as, it leaves the oil boiler, it goes through the pump and nrv, up through the flow valve of the rads, continues up through the flow in the DHW cylinder coil and returns through the return back to the oil burner, it cannot get past the nrv before the solid fuel pump.

I would have attached a sketch but it took me nearly 30 mins to type out this ffs..:)..sorry if the reply drags on a bit and is a bit confusing.

gifted

gifted wrote: »

Nearly every house in Ireland had a solid fuel back boiler for central heating with circulating pumps fitted..long before gas and oil boilers became readily available.

What happens if you just have a solid fuel back boiler and there is a power cut? ...pump fails...water expands up through Flow pipe, through the pump (restriction)...Oftec regs state that if a valve must be used of a Feed and Expansion pipe then it must be the type that cannot be interfered with,so I used a flap type non return valve hence the reason why we fit a lockshied valve on the return pipe going into an expansion vessel on a heating system, I also said that I fitted a safety valve before the pump and check valve...

The water flowing from the oil boiler through the flow pipe cannot go through the back boiler as the check valve will stop it, it will go through the coil in the DHW cylinder and return through the return pipe to the oil boiler and vica versa with the solid fuel...

Draw out a schematic and you will see...back boiler to one side...take flow and return straight off and into the coil in the cylinder..draw in the pump and the check valve on the solid fuel...now draw oil boiler on the other side ...take flow and return from oil boiler and connect into solid fuel flow and return..draw in pump and check valve on flow pipe next to oil boiler.. now draw in a few rads on both circuits,....now follow the flow of water as, it leaves the oil boiler, it goes through the pump and nrv, up through the flow valve of the rads, continues up through the flow in the DHW cylinder coil and returns through the return back to the oil burner, it cannot get past the nrv before the solid fuel pump.

I would have attached a sketch but it took me nearly 30 mins to type out this ffs..:)..sorry if the reply drags on a bit and is a bit confusing.

Personally for safety reasons i don't think it should be the norm with system design to put any valve between a boiler of any fuel type and a tank feeding the boilers cold feed.

Out of interest is the safety valve on this type of system a temperture/pressure valve and does it have the same requirements as a D2 pipe on a unvented cylinder i.e... tundish and copper pipe sized to deal with volume of water/steam if safety valve opens in a worse case situation:eek:

gifted

As far as I remember it was a 3 bar safety valve. i put this system in about 15 years ago, Same size safety valve is common on heating systems today....Out of curiosty Gary, could you follow the schematic details I posted, Just looking at them myself there and it's a little bit confusing

Yep, i can follow it but i'm not clever enough to say if your right or wrong, you can't fit a back boiler like this to a gas installation any that I came across had to replumbed, the only thing I would go by is:http://www.solidfuel.co.uk/pdfs/link_up.pdf

I am a unvented cylinder expert and as your installation is a sealed system it might be worth looking at how a cylinder deals with it's safety, it does have a 6 bar and you have a 3 bar but there is a tundish to warn if there's a pressure issues, a wax capsule to deal with temperture issues and the discharge pipe is sized to deal with the volume of water/steam god forbid if it went pear shaped.

Micky Dolenz

Threads like this always make me feel uncomfortable.

Back boilers should not be fitted by DIY'ers.

shane0007

gifted wrote: »

shane0007 wrote: »

Everything!
What happens if you have a fire lit to heat the parish and there is a power cut or pump failure?
You must have no restrictions on the primary circuit of solid fuel and that includes a circulating pump and most of all a non-return valve!
Your oil boiler will still heat your back boiler and vice versa as it will follow the same route. It is flowing the same direction for each source through the coil so a non-return valve is useless.

Nearly every house in Ireland had a solid fuel back boiler for central heating with circulating pumps fitted..long before gas and oil boilers became readily available.

What happens if you just have a solid fuel back boiler and there is a power cut? ...pump fails...water expands up through Flow pipe, through the pump (restriction)...Oftec regs state that if a valve must be used of a Feed and Expansion pipe then it must be the type that cannot be interfered with,so I used a flap type non return valve hence the reason why we fit a lockshied valve on the return pipe going into an expansion vessel on a heating system, I also said that I fitted a safety valve before the pump and check valve...

The water flowing from the oil boiler through the flow pipe cannot go through the back boiler as the check valve will stop it, it will go through the coil in the DHW cylinder and return through the return pipe to the oil boiler and vica versa with the solid fuel...

Draw out a schematic and you will see...back boiler to one side...take flow and return straight off and into the coil in the cylinder..draw in the pump and the check valve on the solid fuel...now draw oil boiler on the other side ...take flow and return from oil boiler and connect into solid fuel flow and return..draw in pump and check valve on flow pipe next to oil boiler.. now draw in a few rads on both circuits,....now follow the flow of water as, it leaves the oil boiler, it goes through the pump and nrv, up through the flow valve of the rads, continues up through the flow in the DHW cylinder coil and returns through the return back to the oil burner, it cannot get past the nrv before the solid fuel pump.

I would have attached a sketch but it took me nearly 30 mins to type out this ffs..:)..sorry if the reply drags on a bit and is a bit confusing.

That is not true! Firstly, the pumps are on the secondary circuit and not the primary. No non-return valves are on the primary also as non-return valves can stick. In January of this year I was called to a solid fuel system plumbed in your way that blew a hole in a concrete floor!
OFTEC does NOT allow any valves on a f & e pipe. I am my jollies at the moment so I cannot quite the reference number but will do next week. They do allow a valve on a pipe to an expansion vessel so that the vessel pressure can be checked without draining the whole heating system.
By the sounds of it, you have fitted a solid fuel system to a pressurised system as you said you fitted a lock shield valve leading to the expansion vessel.
Finally, if both systems are sharing the flow pipe passing through the cylinder then both will share the returns. The returns will both lead back to each boiler in the direction of the non-return valves thus rendering the void. Non-return valves will only work if the flow is against them!

shane0007

Micky Dolenz wrote: »

Threads like this always make me feel uncomfortable.

Back boilers should not be fitted by DIY'ers.

+1

Micky Dolenz

No valves or restricters on expansion pipe. Back boiler must always have an unrestricted flow and return (primary circuit) to cylinder or buffer tank. Back boiler must always be vented unrestricted. Safety valves are always fitted to any heat producing appliance. They are not to be used to side step any other safety features inc expansion vent pipe.

gifted

Gary,

the system was changed over to an open system as i mentioned the F & E tank in my post.

Shane,
Read my post again Shane and you will see that it is an open system...
the water will take the easiest route so it will not go through the boiler as the pump will keep the check valve closed, draw out the schematic as i suggested and you will see that..

Mickey,

You called me a DIY'r. you do not know me yet you labelled me . I am a qualified plumber for the last 22 years, half of them a a foreman. I have qualifications in solar, biomass, geothermal, GID,GIS, OFTEC. I was a member of RGII but found them useless.

Micky Dolenz

gifted wrote: »

Gary,

the system was changed over to an open system as i mentioned the F & E tank in my post.

Shane,
Read my post again Shane and you will see that it is an open system...
the water will take the easiest route so it will not go through the boiler as the pump will keep the check valve closed, draw out the schematic as i suggested and you will see that..

Mickey,

You called me a DIY'r. you do not know me yet you labelled me . I am a qualified plumber for the last 22 years, half of them a a foreman. I have qualifications in solar, biomass, geothermal, GID,GIS, OFTEC. I was a member of RGII but found them useless.

I wasn't having a go, I was more speaking in general.

However as you are a professional, why did you not fit a dual coil cylinder with a gravity primary circuit?

shane0007

gifted wrote:

OFTEC regs state that if a valve must be used of a Feed and Expansion pipe then it must be the type that cannot be interfered with,so I used a flap type non return valve hence the reason why we fit a lockshied valve on the return pipe going into an expansion vessel on a heating system, I also said that I fitted a safety valve before the pump and check .

OFTEC does not state this.
I am only quoting from your statement.
The non-return valve will not stop the boiler heating if the heat is returning to the other boiler in the direction of the flow of the non-return valve. As the share the coil this will now eliminate the effectiveness of a non-return valve.
A dual heating system should always be plumbed so that both system can be on at the same time and is easily achieved if designed and installed correctly. This is basic stuff here and I am surprised to hear a person with your experience and training speaking in this manner. It is condusive of a DIY'er.

gifted

gifted wrote: »

Gary,

the system was changed over to an open system as i mentioned the F & E tank in my post.

Sorry I thought you had a check valve on the cold feed which would obviously make it a closed system:)

gifted

Hi Gary,
No bother

Hi Mickey,
The reason I did not fit a dual coil was because of money, the people i was doing the job for were stuck for money. The solid fuel central heating was already installed and they wanted the oil boiler connected to the heating system. In an earlier post I said that the system was changed from pressurised to open, I was wrong, it was always an open system, apologies for any confusion there.

Hi Shane,
I'm inside in work at the moment but when I get home I will get the OFTEC book that I took that statement out of. In the meantime can I ask you to try something...draw a solid fuel boiler (square box) and draw an oil boiler on the same page ..link flow and return connections by drawing 2 lines from each boiler..put pump on flow pipe by each boiler and check valve as well..now just draw in a bypass on the solid fuel side...turn on the pump at the oil boiler..the water will travel right across to the check valve on the solid fuel side but will not get through..it will go down the bypass instead..this water will travel back to the oil boiler via the return pipe..it Cannot go through the solid fuel boiler by the return pipe as the pressure from the oil boiler pump will keep the flap closed..the water is feeling restriction at this point so it will take the easiest route back to the oil boiler...going mad here that I can't sketch it out..:)

The people i was doing the job for told me that the oil was for the morning and solid fuel would do the work in the evening..

Micky Dolenz

I can picture how you did it.

However you've done something I would never do. You put two valves on a primary circuit (pump valves) and 2 restricters, pump and nrv. If by chance a valve is turned off, it could end badly. I know chances are slim but there is a chance.

I'd always think worse case scenario and design the system to avoid it at all cost.

As a side point, do OFTEC give advice on solid fuel appliances or was it for an oil applaince.

shane0007

gifted wrote: »

Hi Gary,
No bother

Hi Mickey,
The reason I did not fit a dual coil was because of money, the people i was doing the job for were stuck for money. The solid fuel central heating was already installed and they wanted the oil boiler connected to the heating system. In an earlier post I said that the system was changed from pressurised to open, I was wrong, it was always an open system, apologies for any confusion there.

Hi Shane,
I'm inside in work at the moment but when I get home I will get the OFTEC book that I took that statement out of. In the meantime can I ask you to try something...draw a solid fuel boiler (square box) and draw an oil boiler on the same page ..link flow and return connections by drawing 2 lines from each boiler..put pump on flow pipe by each boiler and check valve as well..now just draw in a bypass on the solid fuel side...turn on the pump at the oil boiler..the water will travel right across to the check valve on the solid fuel side but will not get through..it will go down the bypass instead..this water will travel back to the oil boiler via the return pipe..it Cannot go through the solid fuel boiler by the return pipe as the pressure from the oil boiler pump will keep the flap closed..the water is feeling restriction at this point so it will take the easiest route back to the oil boiler...going mad here that I can't sketch it out..:)

The people i was doing the job for told me that the oil was for the morning and solid fuel would do the work in the evening..

I understand you are trying but you are still wrong. You cannot install a system to suit a particular client. It must be installed so that a child can operate it. What happens if they sell the house or rent it out? Regs are there for the protection of the occupant and does not allow financial reasons to dictate the core of the install. If the occupant cannot afford to have it installed correctly then it is not installed until they can.
Once you check your books, you will find that no valves whatsoever are allowed on an osvp or on a f & e pipe.

gifted

Micky Dolenz wrote: »

I can picture how you did it.

However you've done something I would never do. You put two valves on a primary circuit (pump valves) and 2 restricters, pump and nrv. If by chance a valve is turned off, it could end badly. I know chances are slim but there is a chance.

I'd always think worse case scenario and design the system to avoid it at all cost.

As a side point, do OFTEC give advice on solid fuel appliances or was it for an oil applaince.

Hi mickey,

(1) The only thing I put on the flow pipe was the NRV and the safety valve, as I said in an earlier post, the solid fuel system was already installed,pump included. As I,ve stated before as well, nearly every house in Ireland in the 80's had a pump fitted to either the Flow or the Return pipework where it entered the boiler and the open vent was taken off the flow pipe at the entry to the cylnder and brought to the F & E tank in the attic, would you agree on that?
(2) Where I put the safety valve on the solid fuel system ie: between the boiler and the pump, if I was to put the open vent pipe there then it would be right?...but I couldn't cos the system was already installed and the people said floors or walls were not to be damaged.
(3) In relation to your question, the only place where I could find solid fuel boiler in the OFTEC book was in a sketch for a dual system..the sketch showed the 2 systems not linked together at all, oil boiler done a certain amount of rads and the solid fuel done the rest of the rads, both done the DHW cylinder.
(4) The people I done the job for were my Aunt and Uncle so no arguing with them on anything. Thats how I know the system is still working perfect..I also done it in the evening for them as a favour..no money

gifted

shane0007 wrote: »

I understand you are trying but you are still wrong. You cannot install a system to suit a particular client. It must be installed so that a child can operate it. What happens if they sell the house or rent it out? Regs are there for the protection of the occupant and does not allow financial reasons to dictate the core of the install. If the occupant cannot afford to have it installed correctly then it is not installed until they can.
Once you check your books, you will find that no valves whatsoever are allowed on an osvp or on a f & e pipe.

Hi Shane,

First of all do you agree that the solid ful boiler cannot get hot through the return pipe with the NRV on the flow and the pressure of the oil burner pump keeping the flap closed?

The particular client was me Aunt and Uncle and no money changed hands, I done it in the evening as a favour to them.thats how I know that the house would never be sold or rented out

The job was done over 15 years ago, don't even know if there was regs even out then...none of the older plumbers I worked at the time with ever mentioned regs, situation is completly different today.

In OFTEC book Technical Book 4 1st Edition 2006 on page 2(4) it states " If any valves are fitted in pipework used as a route for the feed and expansion pipe, they must be of a type, which cannot be easily adjusted by unathorisedpersons."
I fitted flap type NRV..non adjustable

gifted

The op asked the question can a back boiler be connected into the existing heating system..in my opinion yes it can, I also believe that you do not have to fit a dual cylinder as well....The one change I would make to the system I installed would be to change the safety valve by the solid fule boiler for an open vent to the F & E tank..

Now, my little fingers are beat from typing..any more comments ye can skype me..:D:D

shane0007

gifted wrote: »

shane0007 wrote: »

I understand you are trying but you are still wrong. You cannot install a system to suit a particular client. It must be installed so that a child can operate it. What happens if they sell the house or rent it out? Regs are there for the protection of the occupant and does not allow financial reasons to dictate the core of the install. If the occupant cannot afford to have it installed correctly then it is not installed until they can.
Once you check your books, you will find that no valves whatsoever are allowed on an osvp or on a f & e pipe.

Hi Shane,

First of all do you agree that the solid ful boiler cannot get hot through the return pipe with the NRV on the flow and the pressure of the oil burner pump keeping the flap closed?

The particular client was me Aunt and Uncle and no money changed hands, I done it in the evening as a favour to them.thats how I know that the house would never be sold or rented out

The job was done over 15 years ago, don't even know if there was regs even out then...none of the older plumbers I worked at the time with ever mentioned regs, situation is completly different today.

In OFTEC book Technical Book 4 1st Edition 2006 on page 2(4) it states " If any valves are fitted in pipework used as a route for the feed and expansion pipe, they must be of a type, which cannot be easily adjusted by unathorisedpersons."
I fitted flap type NRV..non adjustable

Sorry no I do not agree for reasons I previously outlined.
Money changing hands or not is irrelevant as you deemed yourself to be a competent person by agreeing to undertake the works in hand and therefore must install as per the regulations of that time period and yes of course there was regulations 15 years ago. Again, if you deemed yourself competent to carry out the works then that means as per the regs.
Upon my return next week I will quote the relevant OFTEC section reference.

gifted

shane0007 wrote: »

Sorry no I do not agree for reasons I previously outlined.
Money changing hands or not is irrelevant as you deemed yourself to be a competent person by agreeing to undertake the works in hand and therefore must install as per the regulations of that time period and yes of course there was regulations 15 years ago. Again, if you deemed yourself competent to carry out the works then that means as per the regs.
Upon my return next week I will quote the relevant OFTEC section reference.

Grat stuff,I look forward to continuing this discussion, can you also get me the regulations that were available 15+ years ago as well?

You also stated in a previous quote "A dual heating system should always be plumbed so that both system can be on at the same time and is easily achieved if designed and installed correctly"..Why would you have the 2 boilers working at the same time?..The main reason people get the dual system is to have either one or the other system working..would you not agree?

Talk to you soon

shane0007

gifted wrote: »

Grat stuff,I look forward to continuing this discussion, can you also get me the regulations that were available 15+ years ago as well?

You also stated in a previous quote "A dual heating system should always be plumbed so that both system can be on at the same time and is easily achieved if designed and installed correctly"..Why would you have the 2 boilers working at the same time?..The main reason people get the dual system is to have either one or the other system working..would you not agree?

Talk to you soon

For the regs you can check www.environ.ie archives.
Regarding your comment on the two systems on together, again I would disagree. Solid fuel systems can never achieve continuous outputs as high as an oil boiler and therefore the two systems will be required to be on together to achieve all radiators with overall similar high temperatures. The oil boiler will go out on temperature quicker and for longer time periods thus saving on oil usage.

gifted

shane0007 wrote: »

For the regs you can check www.environ.ie archives.
Regarding your comment on the two systems on together, again I would disagree. Solid fuel systems can never achieve continuous outputs as high as an oil boiler and therefore the two systems will be required to be on together to achieve all radiators with overall similar high temperatures. The oil boiler will go out on temperature quicker and for longer time periods thus saving on oil usage.

So you would link the oil flow pipe into the solid fuel flow pipe?...would the pump on the oil boiler flow pipe not push the flow water back through the solid fuel boiler and in turn back out the return of the solid fuel boiler?

Do you tell the client that when they have the fire lighting that the oil boiler will be working as well?...I would imagine that most peoples reaction would be that of surprise?..I presume the reason they got the solid fuel was not to be using the oil boiler ?

What drives the heat around the house when the oil boiler goes off?..I presume the pump will go off as well?..If it's a gravity system then fair enough..what happens if it's not though?

Are you saying that soild fuel back boilers not up to the job of heating a house even though they have been around for god knows how long?..I have yet to go into a suppliers premises of solid fuel back boilers and see a notice next to them telling people that they must have another boiler to top up the temp of the system as the solid fuel boiler will not...:)

Thank you for the link. I'll check it out.

shane0007

gifted wrote: »

So you would link the oil flow pipe into the solid fuel flow pipe?...would the pump on the oil boiler flow pipe not push the flow water back through the solid fuel boiler and in turn back out the return of the solid fuel

No they are connected through the secondary circuit. Do I really need to explain these basics to a 22 year experienced plumber? If you search my previous posts I have posted a PDF drawing that I drew up previously of how the two systems should be connected.

gifted wrote: »

Do you tell the client that when they have the fire lighting that the oil boiler will be working as well?...I would imagine that most peoples reaction would be that of surprise?..I presume the reason they got the solid fuel was not to be using the oil boiler ?

Yes and no they do not look surprised unless they have had experience before of a poorly installed system.

gifted wrote: »

What drives the heat around the house when the oil boiler goes off?..I presume the pump will go off as well?..If it's a gravity system then fair enough..what happens if it's not

The pump will drive the heat around as it will still have power. The burner will not fire as it will be turned off by the boiler stat. The solid fuel pump will be on as it will receive its power from a pipe stat located on the flow from the back boiler.

gifted wrote: »

Are you saying that soild fuel back boilers not up to the job of heating a house even though they have been around for god knows how long?..I have yet to go into a suppliers premises of solid fuel back boilers and see a notice next to them telling people that they must have another boiler to top up the temp of the system as the solid fuel boiler will

Yes solid fuel will never give a continuous output like gas or oil. It has approx 50% kwh of output compared to oil or gas and then it has to deal with its own moisture content. For example, drive ash will have approx 25% moisture content and a kg of ash has approx 5khw of energy. Much of this kwh will be used in burning off the moisture content first. This is why undried timber gives off little or no heat. All of its energy is used to burn off the moisture within it.

Now back to the pool :-)

gifted

shane0007 wrote: »

No they are connected through the secondary circuit. Do I really need to explain these basics to a 22 year experienced plumber? If you search my previous posts I have posted a PDF drawing that I drew up previously of how the two systems should be connected. Can't find that PDF, please repost it


Yes and no they do not look surprised unless they have had experience before of a poorly installed system. Very vague answer


The pump will drive the heat around as it will still have power. The burner will not fire as it will be turned off by the boiler stat. The solid fuel pump will be on as it will receive its power from a pipe stat located on the flow from the back boiler. ok



Yes solid fuel will never give a continuous output like gas or oil. It has approx 50% kwh of output compared to oil or gas and then it has to deal with its own moisture content. For example, drive ash will have approx 25% moisture content and a kg of ash has approx 5khw of energy. Much of this kwh will be used in burning off the moisture content first. This is why undried timber gives off little or no heat. All of its energy is used to burn off the moisture within it. When I talk of solid fuel back boiler, it is coal that I presume that is being used

Now back to the pool :-)

.lucky bas**rd lol

shane0007

I will repost it next week.
Nothing vague about that. It makes sense to always install a safe and working system and therefore it is expected by the client.
Coal if I can remember is about 7kwh per kg. Solid fuel open fires with back boilers are about 40% efficient so in order to keep up with a standard efficiency of approx 80% 25kw oil or gas boiler, you will have to keep shovelling approx 7kg of coal every hour into it. If you don't keep it up, the kwh will drop and the radiators will become cooler.
At least with dual the system can be automatically topped up when needed or turned off when the solid fuel is meeting its obligation.

JohnnieK

shane, put the phone down and enjoy your holiday you lucky F**k. The best I can do is two nights in the Killiney Castle. Wait! there's a pool there too!!:D:D;)

gifted

shane0007 wrote: »

I will repost it next week.
Nothing vague about that. It makes sense to always install a safe and working system and therefore it is expected by the client.
Coal if I can remember is about 7kwh per kg. Solid fuel open fires with back boilers are about 40% efficient so in order to keep up with a standard efficiency of approx 80% 25kw oil or gas boiler, you will have to keep shovelling approx 7kg of coal every hour into it. If you don't keep it up, the kwh will drop and the radiators will become cooler.
At least with dual the system can be automatically topped up when needed or turned off when the solid fuel is meeting its obligation.

The system I fitted over 15 years ago is still working perfect today, only change I would have made would be to install the open vent next to the safety valve on the solid fuel boiler but aunt and uncle wouldn't let any dirty work proceed, They came to me asking me to do it for them and I came up with the system that suited them and the solid fuel boiler that was there already, they were very happy with it and to be honest I would do the same again today.

I look forward to seeing the sketch

Go on and enjoy your pool

gifted

Ay last I have managed to upload a sketch.

shane0007

Back in the land of nod :-(

Here's the diagram...

Had a look at your sketch. In truth, it may or may not work, as equally the return through the solid fuel could keep the non-return valve open. Whether it works or not, it would certainly not be an install I would undertake in that manner. Too many "what if's" when pump failure or power cuts occur.

gifted

shane0007 wrote: »

Back in the land of nod :-(

Here's the diagram...

Had a look at your sketch. In truth, it may or may not work, as equally the return through the solid fuel could keep the non-return valve open. Whether it works or not, it would certainly not be an install I would undertake in that manner. Too many "what if's" when pump failure or power cuts occur.

It works perfect even though you might find it hard to admit it

As I keep having to remind you it's a job that I done over 15 years ago and the solid fuel was already installed by someone else..I just connected in the oil

The return water will always take the the path of least resistance so it will not keep the NRV flap open.

"what if's"....On my sketch there is a 2nd open vent fitted and a safety valve If there was a power failure.

I had a look at your sketch, very nice,..have one query though, when the oil boiler is running and the flow pump circulates the water around, what stops it from pumping through the pump on the secondary circuit on the solid fuel sytem and circulating through the return on the solid fuel boiler?

Also, I have been doing a bit of research on this topic for the last few days and any schematic I have come across shows the two heating circuits NOT combined...solid fuel does a certain amount of rads, usually in the centre of the house and the oil does the rest of the rads around the house...OFTEC and Domestic Design Guide 2008 are two books which show that.

gifted

gifted wrote: »

It works perfect even though you might find it hard to admit it

As I keep having to remind you it's a job that I done over 15 years ago and the solid fuel was already installed by someone else..I just connected in the oil

The return water will always take the the path of least resistance so it will not keep the NRV flap open.

"what if's"....On my sketch there is a 2nd open vent fitted and a safety valve If there was a power failure.

I had a look at your sketch, very nice,..have one query though, when the oil boiler is running and the flow pump circulates the water around, what stops it from pumping through the pump on the secondary circuit on the solid fuel sytem and circulating through the return on the solid fuel boiler?

Also, I have been doing a bit of research on this topic for the last few days and any schematic I have come across shows the two heating circuits NOT combined...solid fuel does a certain amount of rads, usually in the centre of the house and the oil does the rest of the rads around the house...OFTEC and Domestic Design Guide 2008 are two books which show that.

Hiya,

I'm still waiting for an answer to the above..

also still waiting for... "Upon my return next week I will quote the relevant OFTEC section reference."

shane0007

gifted wrote: »

Hiya,

I'm still waiting for an answer to the above..

also still waiting for... "Upon my return next week I will quote the relevant OFTEC section reference."

Apologies. Still in holiday mode ... I wish....

In answer to your question there is no circulation in that part of the system when the oil boiler only is on, but of course when both system are on, there will be acceptable circulation in both circuits.

OFTEC reference: Book 4 (3.3.1) General Paragraph 2

"The feed and expansion pipe must be able to keep the boiler full of water no matter what happens to any valves or controls fitted to the system. Therefore, no valves are permitted to be fitted within the feed and expansion pipework."

I hope this now answers your questions and I think we have flogged this one enough. This is basic stuff and should be common knowledge for trained competent persons. Good design will always result in a reliable and trouble-free system. It is not my place to warrant or condone a practice that is due to another installer, another time, another etc, etc. but I can only comment on what is best practice and what should be done when found. I am sure if a poorly installed system is pointed out to client and the issues that could potentially arise from that, then most clients will most likely opt for the better installation. It will most definitely result in further referral work and duly so.

gifted

shane0007 wrote: »

Apologies. Still in holiday mode ... I wish....

In answer to your question there is no circulation in that part of the system when the oil boiler only is on, but of course when both system are on, there will be acceptable circulation in both circuits.

OFTEC reference: Book 4 (3.3.1) General Paragraph 2

"The feed and expansion pipe must be able to keep the boiler full of water no matter what happens to any valves or controls fitted to the system. Therefore, no valves are permitted to be fitted within the feed and expansion pipework."

I hope this now answers your questions and I think we have flogged this one enough. This is basic stuff and should be common knowledge for trained competent persons. Good design will always result in a reliable and trouble-free system. It is not my place to warrant or condone a practice that is due to another installer, another time, another etc, etc. but I can only comment on what is best practice and what should be done when found. I am sure if a poorly installed system is pointed out to client and the issues that could potentially arise from that, then most clients will most likely opt for the better installation. It will most definitely result in further referral work and duly so.

What stops it from circulating?...

shane0007

gifted wrote: »

What stops it from circulating?...

I am getting bored with this one. Final answer! Follow with your finger from the circulating pump at the boiler along the circuit to radiators and back to the return to the oil boiler. As the pump is now pulling in negative pressure from the return this will enduce circulation from that return. When there is no pump on in the solid fuel circuit, there will be no enducement to reverse circulate. As I said, this will not circulate whilst any one system is on and the other is off. It will, of course, circulate through both circuits whilst both pumps are on, but this is intended.