Why is the plumbing system the way it is here?

[EddieM]

Unvented cylinder with system boiler, and a house approx 20m below a reservoir if you insist on 60ft head (= 2bar)

60ft head no that's for *****'s I want 90 ft head 2 showers simultaneously no pumps. Surely it depends upon the flow ??

 

[dextrous]

So now you want 3 bar? As you've no doubt worked out by now 1 bar is approx 10m of head. It does depend on both pressure and flow rate.

To get an understanding of this, think of a common hose with an adjustable spray head. You could get a varying flow rate regardless of the fixed incoming pressure by adjusting the spray. And if you used a wider bore hose, then the same applies. It is entirely possible to have exactly the same flow rate using a narrow hose with high pressure as a wide hose with a low pressure. So both flow rate and pressure come into the calculation for a powerful shower.

 

[mickyg]

http://cgi.ebay.co.uk/300Ltr-Unvented-Hot-Water-Cylinder-Direct-Brand-New_W0QQitemZ280381485607QQcmdZViewItemQQptZUK_Home_Garden_Hearing_Cooling_Air?hash=item414809f227&_trksid=p3286.c0.m14

isnt it illegal to sell an unvented cylinder now without the water set and EV??

 

[EddieM]

nope it's not about BAR, my jet wash wallops out 110 BAR, but would make a ****e shower.

 

[Agile]

I expect its only illegal to INSTALL them!

 

[mickyg]

I expect its only illegal to INSTALL them!

no im fairly sure its illegal to supply as well.

 

[ajstoneservices]

yes you can sell em, but cant legally install them.

 

[mickyg]

to comply with Building Regulation G3 they must be supplied with a complete package of controls - either factory fitted, or supplied as an unvented kit

Any unvented hot water storage system should be in
the form of a proprietary unit or package

 

[ajstoneservices]

Mick that doesn't prevent them being sold legally but it should prevent them being installed, and yet it doesn't.

 

[mickyg]

I must be misinterpreting the regulations then. I would thought if someones selling something they're supplying it, but then I guess when you stick it in the van and take it to missus you now become the supplier as well....just another unenforcable regulation i guess

 

[dextrous]

nope it's not about BAR, my jet wash wallops out 110 BAR, but would make a s***te shower.

But it would get you clean
Anyway, you brought up the subject of bar when you specced 60 then 90 foot of head. Nar na na nar na

A good shower would probably need about 10 to 15 lpm, so for 2 to be run simultaneously you'd need about double this incoming mains supply.

 

[dextrous]

I must be misinterpreting the regulations then. I would thought if someones selling something they're supplying it, but then I guess when you stick it in the van and take it to missus you now become the supplier as well....just another unenforcable regulation i guess

There is also the case for replacement parts - it is entirely possible to buy one bit without being forced to have to buy the whole package.

 

[dextrous]

I expect its only illegal to INSTALL them!

Is there a haziness anywhere in this - a bit like (I hate to mention it) installing or repairing your own gas appliances?

 

[ajstoneservices]

I think the regulation is pretty clear, anything over 15l and you must have a G3 ticket to install or service an unvented cylinder.

 

[LeeUK]

In our places in France

150 - 200 litre unvented hot water tanks
shower run off bath taps, one of which the hot water tank was about 15-20metres of 14mm copper pipe away