Pressure vessels and leaking overflow

[Dan Robinson]

It's 3 bar above atmospheric.

You also need to pressurise the vessel against atmospheric pressure. Not 170 litres of water.

 

[John D v2.0]

It's 3 bar above atmospheric.

You also need to pressurise the vessel against atmospheric pressure. Not 170 litres of water.

See what you mean, but that's why I said open a tap and leave it open. That vessel has a diaphragm so it won't get bigger than 18l.
Maybe you mean the tap opened should be below the unit so the weight of the water is off the vessel, but even if it's in the ground floor and you open a tap upstairs that's only going to add about 0.3 bar at the most.

 

[Dan Robinson]

No... think where the tap is in relation to the vessel.

 

[John D v2.0]

No... think where the tap is in relation to the vessel.

Tap is after the vessel topologically, and physically above. If it's 3m above but open then that leaves 3m head or 0.3 bar. If it was a boiler that would be significant but for an unvented I thought not, are you saying it is?

I suppose your point is really that there's a way to drain the wet side of the tank easily then it's all standard.

I'm still not sure the issue about charging to 3 bar, isI say that's ok?