How to calculate radiator volumes?

Whole system would have drained I think.

 

If you work on the basis of gravity. Everything upstairs would empty, everything downstairs, but above the level of where they drilled the pipe would be empty, anything below where they drilled the hole would still have water in it.

If you start with the pipes alone, every 1m of 22mm pipe = 1.5L and 0.7L for 15mm

As a VERY rough guide, the flow areas in the rad's won't be far off 15mm values, so count the number of ribs x height x 0.7

 

Me White, on what floor was this pipe?

And how large was the hole drilled?

Was the drill bit left in place, or some attempt made to plug it - even with a sprig of timber?

There is a very good chance that your system has not 'drained' at all, but only released its pressure - which would have been around 1 bar and probably related to - I dunno - 2 or 3 litres of water?

Yours is a sealed system, so for water to drain oot air has to get in. Chances are all the rads upstairs are still full of water (don't try 'bleeding' them 'cos that will chust draw in air...), and likely that most of the rest of your system - certainly the rads - will still be filled too.

When you drill into a pipe on a sealed & pressurised system, it'll be dramatic for a few minutes as the water sprays oot under pressure, but once the pressure has equalised, the chances are it'll stop. Or chust drip.

 

Empty rads ring "hollow" when tapped. Using data from Stelrad, the rads hold abut 50 litres At a rough guess the total system volume will be about 80 litres.

 

Or, when you undo the rad valves, empty rads don't make such a mess.

But I prefer Sam's method...

 

Cheers, DWhite.

How silly for the first guy to chust leave that pipe as it was - had he even wrapped a piece of tape around it it would have stopped leaking - no air getting in = no water getting oot.

As you say, the splurts of water coming out were following glugs of air being drawn in.

Having said that, chust because another guy announced "The system has drained" does not make it so - it sounds to me like a general comment, pure assumption.

Did he check that each rad was empty? Has anyone checked this?

And, being a sealed system, turning off the cold mains stopcock wouldn't have made any difference.


Having said all that, the engineering company had the easy opportunity at the time to prevent this becoming a significant issue. Ie:they wouldn't have been able to stop the initial pressurised 'fountain', but that would only have comprised a few litres of water and presumably lasted only a minute-ish?

The water that came out under pressure would have been the difference between the actual system volume, and the extra bit that's forced in under pressure to fill the expansion vessel and raise the pressure to ~1 bar. I'm guessing this will be about 4 litres?

Had he - or especially the 5-hour late plumber they sent - simply wrapped binding over that hole, the issue (literally...) would have stopped there.

So - yep - get them for all you can .