Tiny CH Pipes.

[WaterTight]

Not sure what size they are. Seen them once or twice. Friend's house has them feeding all rads. A decorator put a rad back on and the pipe bent double. What's the point/benefit of them?

 

[PlumbBobBob]

they will be either 8mm or 10mm the point of them is that they were easy to install.

 

[fuzzy]

normally 10mm..

 

[Billy Bob Bob]

have seen a lot of 8mm used cant take a knock

 

[Dotty]

Daren't look at 'em and they start leaking!

 

[WaterTight]

So if you came across a rad where two 10mm pipes pop straight out of solid floor and tiled floor that they don't want digging up... and one pipe is bent too badly for anything to pass through it, there's no pipe to play with and the nearest rad to tee off is f'ing miles away and they say the rad doesn't work since it was bent...what would you suggest?

Give up I'm guessing. Can you squeeze the pipes back into shape with grips or something?

 

[Billy Bob Bob]

i would suggest they start looking for tiles cant you get a drop to it? is it all under floor?

 

[dontknowitall]

I'd be careful how you go. If you remove the radiator and something goes wrong, they might get you to replace everything at your expense. Bending the pipes back into shape probably won't work and might end you in more trouble, e.g. a hole in the pipe if you touch it. Only way, in my opinion, is digging the appropriate floor tile(s) up.

 

[Plumbstar Tom]

unless you can carefully cut the pipe and pop a coupler on like this for example

Conex Push Fit 270 Straight Coupler 10mm - NoLinkingToThis, Where the Trade Buys

But again if it goes wrong you are digging up the floor

They use 10mm copper as its cheaper, lighter and can be bent easily and accuratley with simple hand benders rather thab the big jobbies for 15mm and 22mm copper

 

[kay-jay]

is the rad on a stud wall? can you maybe get access from the adjoining room from beneath the floor boards. if possible this will prevent the need to rip up tiling.

KJ

 

[Bernie2]

Hmm!

10-8mm is easier to install and can be threaded through joists like the lady job "Sparks" do with their cable .

I also think that at one time they thought the less water in a system the less fuel you used to heat it so they where more economic and cheaper to run.
The practical side though, they seemed to block up with the likes of magnetite, you have probably seen how thick it can get in a 15mm system imagine it in a 8 -10mm system.

Also air locks where hard to remove.

The actual installation also allowed for manifolds to be fitted with local control, although you can do the same with 15mm.

Another problem is that with small pipes you need a high head pump to push it through the added resistance and so increasing water speed and erosion.

Incidentally mini bore is the same as micro bore.

Its just that one company, I think it was Yorkshire who made 8 - 10mm fittings and pipe referred to the sizes as micro bore and another company called it mini bore.

 

[charliejamesuk]

A newish housing development near me has all the basins done in 8 or 10mm plastic (hot & cold). The fittings they use for elbows, couplings, etc appear to be a white/grey push fit fitting.

Anyone know what I'm on about? I'll try and take a snap next time..

 

[Plumbstar Tom]

as in the domestic water is in 8 - 10 mm plastic pipe work?

If so thats not the norm

 

[ferret]

as in the domestic water is in 8 - 10 mm plastic pipe work?

If so thats not the norm

Not the norm but much better if they are installing combi,s its about time we started installing as the rest of europe , it will work a lot better , I did this in a 5 bed house I built back in 1990 and it was excellant , mind you it was copper not plastic.

 

[Toddyplumb]

Agree with ferret there we should be looking at this for mains pressure systems . Ive done it a few times on basins and WC,s.
Think of the water you would save if you ran 10mm pipes from a central point at the cylinder or combi to basins . And maybe 15mm for bath.

 

[moony]

if its on a combi thgen i'll run basin and w.c in 10mm. dont see any problems with that

 

[Billy Bob Bob]

i always use 10mm on basins and bogs if a combi or high pressure system been doing this for years

 

[pauls]

ive used 10mm on a basin before but that was only because it was on a pressurised unvented system

 

[Bernie2]

As said, some people don't like 8-10mm because of the noise associated with having to use extra force to get the water to circulate. Its not new stuff its been out for donkeys years.

Speaking for myself I prefer 15mm, but have installed mini bore as well. I prefer 15mm because I don't like to strain the system by having water whizzing around it at break neck speed to try and overcome pipework resistance.

Lets be honest which would you prefer, getting a swipe off a bus going past at 60mph or one going at 20mph?

Well that is how a pipe wall must feel.

We used 8mm plastic on a job and following manufacturers instructions clipped it every 250mm or so. It just simply went into skipping ropes in between each clip. So you have got to fiddle about using lay boards. By the time you fit layboards you could have the job done with copper. Granted the plastic makes the system quieter.

 

[fuzzy]

i always use 10mm on basins and bogs if a combi or high pressure system been doing this for years

and is it better?

 

[Billy Bob Bob]

its a lot neater and works as well as 15mm

 

[Billy Bob Bob]

cant say i agree bernie 2 i have never found mini bore to be noisy after all it is the norm to pressurise systems nowadays so minibore works particularly well and if you can work it its very neat

 

[moony]

i find it crazy that some people dont come across this size pipe - nearly every system we instal or work on is 10mm, 8 mm less so but still come across it on a weekly basis.

i would never run piepwork to a rad higher than ten mm on a standard install. I dont use manifolds much but i always come down in ten mm on new installs.

agree with gas man get a decent ratchet hand bender and you can do a really tidy job with this size pipe

 

[WHPES]

You can sometimes pop bends out by pushing a piece of bar down which is slightly narrower than the pipe bore.

 

[tackleburger]

Yes, get your grips and squeeze carefully, you don't need much for it to pass if it is a small rad you'll be fine. I have succeded with the same thing several times. Loads of 8mm where I am.

 

[Phil]

I would drain the entire system (something I only do if nessessery) and cut the pipe a few cms above the floor, then 'form' the pipe back into shape with a makeshift swaging tool and solder a 10mm end feed coupler on it. Or if you don't carry 10mm pipe (I don't !) then use 10mm x 15mm couplers on both tails.

When finished it will look better than the pushfit and with solder the pipe can be out of round slightly.

Any chance of a picture?

 

[Bernie2]

Funnily enough, it may be a regional thing, but in the North West small bore 15mm - 22mm seems to be the norm rather than mini bore 10 - 8mm.

My opinon comes not so much from the ease of installation, they can be easy to fit, but on the difficulty of manitaince and what these systems look like after a few years.

Lets be honest, you can't usually see under floor boards, so there is no way you would know an unsupported 8mm plastic pipe was not forming a whole series of low points in a system each of which could be a potential air lock or sediment trap.

And regardless of any noise you still have to wack the pump up to get the water to flow through them. More speed more wear.

 

[WaterTight]

I've only been plumbing a couple of years but have worked with two guys on new builds, refurbs and lots of jobbing work and done about 100 private jobs myself and i've seen pipes smaller than 15mm feeding rads twice. I've either not been observant or they're not all that common where I am (south east coast.)