big flush, massive cistern

[breezer]

saw something interesting today, just wondered has anyone else seen / heard of it?

a big (5 x4x3 feet aprox) tank constantly fills with water (a tap drips) when nearly full it syphons out to............... the main drain.

yes i know its just like how a urinal works, but this one is there because aparently the main drain (in the road) is close to the surface, so the distance form this to building although far, doesnt allow enough "drop"

so to make sure the pipes are flushed they have this big "cistern"

it was in a commercial premises

 

[kevplumb]

apparently not on a water meter then

 

[shaggy]

....and it's ok until someone fixes that dripping tap.

 

[kevplumb]

breezer what size was the outgoing pipework ?
are you sure it wasnt a high level bath

 

[ChrisR]

It's common as muck. Ie that's what you'd use on a farm to either flush your slurry, or irrigate fields without having to pump.
Imagine a big flattish tray like a capital E on its back, pivoted under the centre line so it can rock to and fro. As it moves say to the left, the central divider moves left under the tap so then the half on the right starts filling. Am I making sense?
The siphon is a rather more controlled mechanism, which we see of course on "byelaw" kits on cold water cistern overflows

 

[breezer]

breezer what size was the outgoing pipework ?
are you sure it wasnt a high level bath

i didnt actually look in it, i asked what it was for, the bloke also said it empties very fast, so i guess it must be at least a 4 inch pipe

 

[kevplumb]

can understand the principle
never seen it