dual system..for the expert!!

[buffy27]

existing heating is a firebird heat pack.primaries then come through the wall directly into cylinder ..[it s t'd off to the heating zone before the coil..]
there is a 6 m head pump at bolier which is doing the house perfect.the heating loop goes up to the attick of this bungalow and down to the individual rads in turn ..all works grand [pressurised/sealed system]
now,there is a new 14kw solid fuel stove in place around 7 meter away from hot press..i will have to go up with both pipes in 1 inch copper..my plan is to then vent the flow from the boiler to my new f and e tank[doing away with auto fill.new system will be open vented obviously] after this i am dropping down to my dual cylinder and t- ing into heating zone ...i will put non returns on both boiler returns to prevent them heating when the other is on. .. now my two questions are 1.will there be a serious issie with air locks [can i place the f and e as high as i can and will use air vents in attick to purge the system ] 2 .will there be an issue with the pumps ...one on flow of bolier and other on flow from solid fuel stove .. any idea s on better pump locations ..the oil boiler one will have to stay on flow .. cheers buf.

come on boys..where are all the clever boys gone on me!!! help ..help

 

[migoplumber]

i did try and draw meself a picture of what your trying to do, but didnt quite manage it. forget the head pressures, forget the non return valves for now, can you not just use 1 pump, 2 heat sources to a header and send the pipework off from there.

i may totally of misunderstood your question, post a pic yourself and we can hack it to bits from there !!

 

[buffy27]

i was waiting on reply from one of 3 fella s and u were one of them!!
firstly answer me this question ..have u installed a stove with both flow and return going up the wall into attick ,across the attick for 5 meters and then down into cylinder.[up ,across and down] i will have a pump on the return pipe next to stove [pipe stat on flow] the pump will be pulling from coil and heating zone. thats the stove part!!!!!!

any idea s ..anyone ,,anyone ?????

whats the craic ....any idea s on this one ...
the oil boiler is next to the cylinder [boiler just outside on gable end].the rad pipes go up to the attic[bungalow] from the hot press in 22m and are dropped down to the rads through the stud in 15mm. this system is pressurised and working fine . now , what i want to do is turn the system into an open vented system with an f&e tank in the attick.the reason why i have to make it openvented is because i want to install a solid fuel stove and make it a dual heating system .the cylinder is 300l dual coil and is as i said on the ground flour next to oil boiler[which is a firebird heatpac]
the new stove will be 14kw and will be positioned around 5 meters away from hot press.i cannot chase the flour for the return so have to run both flow and return up to the attic [house is a bungalow] i want to use the stove for heating and hot water aswell as the oil.i have done similar jobs with dual systems ..but never under these circumstance where all the pipe work has to go up to the attic to come back down to hot press and then back up again to go to and from rads.!!!!

any idea s

 

[migoplumber]

soz buffy, dont live here!!

q1 yes. there is no problem whatsoever with up and down pipework on any system so long as flow restrictions are taken into account (in this case neglible) and air is removed (easily done with aav's on both pipes at both high points)

still slightly squiffy over your idea, but from your 2nd paragraph here might be a bit nearer.

the problem with your stove up and over pipe work is that you could have high enough temperatures to turn the water to steam, (air) and your steam will come out your aav's.

i think you need to control the stove primary temps before you send the pipework anywhere.

i am still guessing a bit.

 

[buffy27]

thanks dude.panic on me cos i am startin in the mornin... no one else replied except u ..is it a very difficult question ????...
i think as long as the pipe stat is working then the hot water is drawn away and will not over heat?? i agree with the idea of the air vents [could i close them once system commissioned??].. i will put the expansion on my flow from stove with pump on return next to stove...could i tie into existing 22mm going to and from rads and then continue across to then drop down for the cylinder for coil..
u are a star mate ...kinda dissapointed with some of the other guys on here ..who are generally helpful when i come on with confusing questions!!!! regards buffy //

 

[Renewable M]

Crikey.

this breaches building regs in every way imaginable.

Solid fuel tapped into an existing system is a good one at the best of times.

No gravity heat dump? look that one up.


Not being funny mate but dont touch it, you have no idea. It'll breach building regs in every way.

What happens to your nice shiny circulation pump when there is a power cut???? It doesnt work. Then you have a non controllable heat source with no means of circulation or heat dissipation.

Heat rises, by the way.

Dont do it, please.

btw, this isnt a confusing question, this is stuff that EVERY heating engineer should know off the top of his head. Its simple.

I assume that you are not qualified and dont have any tickets? Not a prob, but beware the dangers. Its not worth the sleepless nights.

 

[buffy27]

no no no no...read the entire posts i made ..i know plumbin dude and do not take chances on safety..the whole thing will be openvented ..the flow from stove going to gradually rise and into f& e !!!!!! i generally also add a bypass and 3bar blow of to solid fuel work .. i have done lots of this type of work and its to the book ..but i cannot find reference to what i am doing in any of my college books or notes !!! read the post again and u may be able to help me..... crossed wires ..no hard feelings

 

[Renewable M]

have replied to your other post, hope I have made more sense!

 

[stevetheplumber]

didnt answer earlier as when i see oil and solid fuel mentioned im sure theres better qualified than me
going up and over isnt a problem best if you can make the fe tank and vents on the highest point rather than troublesome aavs
do a google on an item called a neutralliser wich takes two boilers but basicly is just a header as mig mentioned
pump on each circuit into a header then one pump and controlls to cyl and heating?but not sure if that would be sufficent heat dump for solid fuel
probably been easier if it was some type of heatstore rather than a twin coil cylinder
im rambling a bit just throwing ideas around as not my area
thinking logically the solid is the uncontrolable sytem so start with how that needs to be run and then work out how to incorperate the oil

 

[buffy27]

ya ,,thanks steve.. renewable m stated that the system may work from day one and down hill there after????? if it is open vented and no obstruction to stop it venting then what is the worst thing can happen ..???

 

[stevetheplumber]

ya ,,thanks steve.. renewable m stated that the system may work from day one and down hill there after????? if it is open vented and no obstruction to stop it venting then what is the worst thing can happen ..???

i was under the impression that solid fuel had to have gravity primaries but i may be wrong

 

[Puddle]

Without seeing this job it is hard to comment on proposed instalation
But maybe if I had to do a pipe run like discribed
Would think about linking stove to a heat transfer unit/exchanger unit located above stove and from other side of unit run pipework back across roof and down to link into oil side of system

 

[buffy27]

thanks puddle..my main concern is the idea of going up with both flow and return to attic and then back down to cylinder.there will be no obstruction between stove and expansion tank..so if power fails etc . it can expand ..this is safe !!!!

 

[migoplumber]

i think you have your main concern confused.
main concern is losing heat from solid stove if need be. pipework will be fine. no point in installing aav's if your going to shut them afterwards!!

 

[buffy27]

what would be worst case scenario .. should i leave in aav 's??

 

[bobpape]

What will happen and I have witnessed many times is that on occasion the solid fuel boiler will boil the water which in this case will vent into the loft space but shake the
whole house as it bangs and cracks, all you can do then is draw the fire or try to put it out.

It can not possible to block the primaries, the boiler would blow up.

In the early days of central heating most boilers were solid fuel, it was common for them to overheat

I would be interested in solving this problem as I am considering installing a solar collector on the roof and conecting the flow and return into the existing primaries.

 

[stevetheplumber]

is there room to put cylinder and tank above in loft so you could have gravity primaries to the cylinder

 

[buffy27]

not too sure what u mean about connecting in the solar?? lets leave that one for now.
if i have a continuous open loop between stove and f&e tank what can go wrong..water boiles/ expands ..and is replaced by cooler water as it will circulate back through feed which is tied into return .

steve my problem would be non existent if this were the case ..can u visualise the set up ...flow leaving boiler up the wall and return coming back down wall to boiler..i will vent the flow to f&e tank and tee in feed on return which will provide a convectional heat circuit should the pump fail... keep the idea s coming guys please... not as easy as answering about toilet seats or tap washers !!!!!!we all like a challenge

 

[bobpape]

Buffy
What we have to consider here is the possibility of somthing happening, plumbing is supposed to be designed to be fail safe.

You are right when you say the heat will continue to be transfered into the domestic
but what do you do with the heat when the domestic is satisfied,

You are right when you suggest that you could divert the heat into the radiators but
what do you do with the heat when the radiators are satisfied,

May I suggest that if you want to make use of two boilers using different fuels,
that you use one boiler for heating and the other for domestic (preferably the
controlable boiler for domestic).

 

[buffy27]

the oil cannot come on when the pump on the stove is running ...

 

[Renewable M]

didnt answer earlier as when i see oil and solid fuel mentioned im sure theres better qualified than me
going up and over isnt a problem best if you can make the fe tank and vents on the highest point rather than troublesome aavs
do a google on an item called a neutralliser wich takes two boilers but basicly is just a header as mig mentioned
pump on each circuit into a header then one pump and controlls to cyl and heating?but not sure if that would be sufficent heat dump for solid fuel
probably been easier if it was some type of heatstore rather than a twin coil cylinder
im rambling a bit just throwing ideas around as not my area
thinking logically the solid is the uncontrolable sytem so start with how that needs to be run and then work out how to incorperate the oil

yes but you cannot have the neutraliser as the highest point in the gravity circuit. heat rises. it doesnt then 'fall' and you CANNOT PUMP IT BECAUSE IT CONTRAVENES BUILDING REGS.

 

[peteheat]

Hi Buffy,

14 Kw stove has a lot of heating power in fact some rated at 14 can go to 20 Kw depending on the fuel and how the customer uses the air intake but that's for another day.

The first problem I see is the stove circuit will be "tipping" into the F&E tank because the hot water (flow) will take the line of least resistance.

What may work is an accumulator tank in the attic (similar to a buffer) that could in theory store the heat to be dissipated by a pump to the existing heating system, the header tank is still needed for safety.

You are asking a pressurised system (that is zoned ?) to work as an open vent system, the fact that all the pipe work drops down from the attic means it was designed to be pumped.

The main safety the present system has is no heat can be generated in the event of a power cut, you do not have that luxury with a solid fuel stove.

Most of the older houses started out with old style solid fuel systems, bungalows often had the flow and return running through the middle of the house under the floor in 3/4" with the rads taken off in 1/2" the cylinder would have been beside the stove, cooker / back boiler with short runs in 1" copper.

The advantage in an emergency was the flow would circulate through the cylinder losing heat and even if the cylinder did get very hot it would expand off into the storage tank being replaced by cold so between the cylinder and the F&E tank exploding back boilers were avoided.

Reading your description you want the flow to travel up about 2m (no problem), horizontal 5m and drop approx 1.5 > 2m to the cylinder with the F&E tank somewhere along the way ?

I know that some stove manufacturers used to have a max of 15 feet from the stove / back boiler to the cylinder and if you can find an installer manual on line you will see the cylinder is usually over the the stove with the primary flow and return in 1" copper pipe.

You might get some help with designing the system from System Link I can assure you that without a definite plan in place I would not start working on that job in the morning.

Renewable M and others have given you some very good advice, I suggest that you take the day to find an alternative instead of digging a hole for yourself.

 

[buffy27]

peteheat ..thanks a million.....i am finding it difficult to under stand how the stove can blowup !!!one guy said that the pressure build up will cause this and i mentioned installing a 3 bar blow off and no obstruction between stove and f& e .. some guys gave it real smart to me..which was of no benefit what so ever ,only satisfying there own ego[look at this guy ,,ha ha ,creating bombs ,,ha ha cowboy!!!] i have met a person who seem s to know it all and the rest are playing catch up to his advanced knowledge and thinking ,oh that is a terrible mind set to have !!!

Crikey.

this breaches building regs in every way imaginable.

Solid fuel tapped into an existing system is a good one at the best of times.

No gravity heat dump? look that one up.


Not being funny mate but dont touch it, you have no idea. It'll breach building regs in every way.

What happens to your nice shiny circulation pump when there is a power cut???? It doesnt work. Then you have a non controllable heat source with no means of circulation or heat dissipation.

Heat rises, by the way.

Dont do it, please.

btw, this isnt a confusing question, this is stuff that EVERY heating engineer should know off the top of his head. Its simple.

I assume that you are not qualified and dont have any tickets? Not a prob, but beware the dangers. Its not worth the sleepless nights.

just like to make reference to this post on the basis of its negative ,very unhelpful tone. i have been on this forum a good length of time and have yet to come across this type of smart /know all persona.this guy has not given me a factual answer to the question i pose .just looked down on my lesser intelligence.. the reason i posted on here was to find out information on a specific installation that has popped up..now remember the fact that i have not installed anything ,,nothing ,,and COWBOYS don t go researching pre-installation...the job is off for the moment . why, because obviously i am not comfortable with my plan of action... any more factual information would be very much appreciated !!! thanks for all the helpful replies non -the less,regards ,a young plumber willing to learn always ..

 

[peteheat]

Hi Buffy,

I am not going to answer for Renewable M I have no doubt he well capable of that himself.

Do not be surprised if you see similar replies from me on occasion, this is an open forum not a training academy or a private chat between the apprentice and his foreman.

I accept you are trying your best but sometimes the best way to learn is to read the building regs (as suggested) the man suggests you look up gravity heat dump again I have no problem with that reply because the reader will learn.

It can be very difficult to condense a lifetime of learning into a short post, also take care to remember Joe Public may read one of the posts and thinks he knows enough to undertake that task himself although it is missing a lot of what we see as simple details not worth mentioning and he could blow himself up !

Also worth noting there are a lot of Guys who visit this site who have never had to work with Solid Fuel, the UK has had an excellent natural gas supply for a very long time.

I bet there are tips and tricks many of them know that I certainly have not seen because I operate in an area that until recently was well outside our natural gas network.

I would not expect them to share such information on an open forum with a total stranger maybe you would do well to read between the lines sometimes

All the best.

 

[stevetheplumber]

condensing whats been said it looks like the cylider is going to have to be above the solid fuel to allow it to act as a heat dump can the oil boier do gravity as well?is so use gravity to cylinder from both and join heating f and r through one pump