elp choosing a system, microbore?

[that bloke.]

i live in a very old house, timber framed with wattle and daub walls.
i cant chase pipes into the walls nor can they go under the floor boards. So ive been thinking a micro bore system might be least intrusive? underfloor heating is also a no.
So can anybody give me a run down on how a microbore system works? does it use a central manifold for instance? or is it just the run from a main flow and return to the rads that is micro bore?

[fabio]

I would try stay clear of micro-bore heating systems....i know if there installed right they can be ok...but later on they can cause a few blockages if not treat correct!iam not a big fan of them.you do have 2 manifolds one for the flow and one for the return.......have you considerd surface mounting the pipes and maybe some sort of boxing on the top?you can buy white boxing which clips over the pipe clips from any decent plumb department.....and you can wall paper over them even! just a though?

[that bloke.]

cheers Fabio, boxing them in isnt an option im afraid, the house is 500 years old and there isnt a straight edge or right angle in the place.
if i ran a 22 mil flow and return the lenth of the house (3 bay/2 floors) and T'd off in 10 mil for each rad what is the longest 10mil run i can hope to achieve? is it 5 meters? or would i need to reduce down from 15mil?

[fabio]

How many radiators are you having on the system?what are the size of the rads? make sure you get a boiler with enough kw for what you want.

[plumbster3456]

if it is a pressurised system micro bore is good I know some on here will say no but trust me I have fitted thousands (or maybe hundreds lol) of heating systems some micro bore some half inch and never had a problem but in saying that this has always been full new systems from scratch so dont have info on wether you are tying into existing pipework for your new rads as existing stuff may be full of sludge (could power flush though).
I f system is pressurised go with the microbore 10mm.

[Blackcatgas]

if it is a pressurised system micro bore is good I know some on here will say no but trust me I have fitted thousands (or maybe hundreds lol) of heating systems some micro bore some half inch and never had a problem but in saying that this has always been full new systems from scratch so dont have info on wether you are tying into existing pipework for your new rads as existing stuff may be full of sludge (could power flush though).
I f system is pressurised go with the microbore 10mm.

I agree with plumbstar, Ive put in loads of the stuff, as long as its on a sealed system ie combi and kept topped up with loads of x100 inhibiter or similiar itl be ok, Ive done 5m+ runs of 10mm pipe and the rads have worked lovely, 1000mmx600mm doubles etc.
Its never my first choice but can be made to work satisfactory.

[gas man]

nothing wrong with minibore all i have ever used is 10mm never had a problem its all down to correct installation

[that bloke.]

thanks guys, ive heard some horror stories about small bore systems but when i was plumbing up barratt houses we used 10mm pipe taken off 22mm flow and return and it all seemed to work fine.

i will be using a mix of 15 mm copper and plastic downstairs as i can conceal some pipework and any surface mount will be 15mm copper purely for aesthetics, its the upstairs that i need to use a smaller bore pipe so i can tuck it away out of sight.

so if i were to use 22mil flow and return from the boiler and take each rad off it the mix of 15mm and 10mm shouldnt be a problem? There will be 9 rads feeding off a single 22mil 10 meter f+r run, three of which need to be 10mm.

its a new system , 30kw combi boiler and sealed system.

[GrahamM]

If you are using plastic for your heating runs make sure you use a decent barrier pipe.
Run it 15/22mm as far as you can before reducing to the 10mm. Give a good few hot & cold flushes and as Blackcatgas mentioned, plenty inhibitor and you should have a good system.

[Redvanman]

I would not choose microbore and to be honest, I don't know why any would anyway. It is best left for a 10mm oil supply than running the stuff through your house. I would stick to using 22mm copper on your flow and return and branch down to 15mm for the rad feeds.
Microbore comes in coils and it is very difficult to get clean straight lines for your plumbing work. You can get blockages with small bits of stubborn solder that won't flush out before commissioning. Don't use push fit plastic either, vermin just love to chew that stuff..!

[gas man]

Microbore comes in coils and it is very difficult to get clean straight lines for your plumbing work.
depends how skilled you are

[plumbster3456]

microbore comes in coils and it is very difficult to get clean straight lines for your plumbing work.
Depends how skilled you are

exactly

[fuzzy]

i live in a very old house, timber framed with wattle and daub walls.
i cant chase pipes into the walls nor can they go under the floor boards. So ive been thinking a micro bore system might be least intrusive? underfloor heating is also a no.
So can anybody give me a run down on how a microbore system works? does it use a central manifold for instance? or is it just the run from a main flow and return to the rads that is micro bore?

yes it works do you know your heat losses?

[that bloke.]

dont know the heat losses yet, i can try to calculate it but it wont be anywhere near close. the house is timber framed with wattle and daub infill's, thatched roof vaulted inside so only the thatch as insulating , the upper floor has no ceiling below , just beams with wide oak floor boards nailed ontop , single glazing, no sealed doors just ill fitting ledge doors, 3 walls are external,exterior rendered in daub, the list goes on so how do you calculate heat loss on an old tea bag like this?

[gas man]

dont know the heat losses yet, i can try to calculate it but it wont be anywhere near close. The house is timber framed with wattle and daub infill's, thatched roof vaulted inside so only the thatch as insulating , the upper floor has no ceiling below , just beams with wide oak floor boards nailed ontop , single glazing, no sealed doors just ill fitting ledge doors, 3 walls are external,exterior rendered in daub, the list goes on so how do you calculate heat loss on an old tea bag like this?

heatloss about a million btus lol