IS my Under Floor Heating installation ruined ?

[doitall]

I have tried it.

Which has the most energy 10 bar water or 10bar air.

Which is most likely to kill you when it falls on your head.

A tonne of Lead or a tonne of feathers.

 

[SimonH2]

I have tried it.

Which has the most energy 10 bar water or 10bar air.

And what was the actual question asked ? You stated categorically that air makes the pipes and joints expand more than water. So to use your figures, which stretches the pipes and fittings most - 10 bar or air or 10 bar of water ?

Which is most likely to kill you when it falls on your head.

A tonne of Lead or a tonne of feathers.

Depends on the format. A ton of feathers may or may not cause injury - if bundled up it will, if loose then it might not. Ditto for the lead - in one lump it certainly would cause injury, but if loose in small pieces it might not. I've probably had a few tons of water fall on me during my life - I'm still here.


But back to your proposition. I'd suggest that the energy in a single UFH pipe, at 3 or 4 bar (why would you use more ?) of air pressure, is not likely to be a serious safety issue - provided you apply some common sense. If the pipe splits or a coupling blows out, then the rate of release of air will be limited by the pipe it has to pass through - in just the same way that when I release an airline with 10 bar in it, as long as I keep hold of the end then the air releases in a safe manner.
Keep the control valves on the manifold almost closed, and you can only release one pipe's worth of pressure rapidly - the rest will release at a slow rate limited by the valve opening.

 

[MJN]

I have tried it.

No you haven't.

Which has the most energy 10 bar water or 10bar air.

Expansion of the pipe is not due to 'energy', but force. Change the units if it helps demonstrate the point. 10 bar = 145 psi. 145 pounds per square inch. That's how much force is being exerted on the wall of the pipe.

Which is most likely to kill you when it falls on your head.

A tonne of Lead or a tonne of feathers.

You are joking, right?

Mathew

 

[doitall]

Can assure you we did, as well as testing with the water at 90c.

You can dream on, I'll not waste my time.

 

[DeltaT2]

I am not for one moment disputing how much more dangerous performing a dry/air test compared with one using water, however to claim that there will be more pipe/joint expansion when using air at the same pressure as when using water is ridiculous.

Just what I was thinking.

The biggest advantage I can think of for wet testing is that the weight of the water will make the pipe less buoyant, and so it will be easier to keep it properly down while the screed is poured. But once the screed has set then that's not a consideration. Common sense suggests that if there's a risk of frost then you either need to empty the pipes (blow them out with air) or put antifreeze in. Blowing them out isn't guaranteed not to leave a low spot that the water will run to and still leave you with a section of pipe that's completely filled and liable to freeze damage.

It can't be an uncommon problem in winter - at least in some areas.

It's clear DIA that none of these 'experts' have ever water pressure tested Underground Water Mains Services & seen it snake out the ground, lifting tons of backfill & moving thrust blocks...........

Air testing is not safe if done by some dafty with a compressor. But in a controlled enviroment & limited joints, it's the only way to do it in a Scottish Mid Winter period. I'm amazed the Builder & Plumber carried out this work in freezing conditions. I mean any Builder worth his salt knows about frost & concrete. Concrete has been about since Roman times, but hey there's not much Roman concrete here in Scotland, not that it was too cold here, we just kept the f.ckers out...........FREEDOM!!!!..........

 

[DeltaT2]

I have tried it.

Which has the most energy 10 bar water or 10bar air.

Which is most likely to kill you when it falls on your head.

A tonne of Lead or a tonne of feathers.

A ton of Lead, trying to get it to the Scrappy before the P.keys get it??!!

 

[MJN]

I'll not waste my time.

That's a relief.

 

[doitall]

I'll not waste my time.

That's a relief.

Don't see you putting a £1000 quid on the table.

Perhaps a £1.00 if thats all you can spare.

 

[Norcon]

I don't see a table.