Cylinder Discharge Problems

[sturharv]

Got a mains pressure cylinder to be positioned under the stairs centrally on the ground floor, the nearest outside wall is 6 or 7 metres away and nearest SVP is 5 metres away.

Can the discharge pipe run in the ground floor screed or insulation? either to outside wall or to an SVP through a waste valve. I assume trying to get the safety discharge out is a common problem.

 

[manortim]

stick a 40mm waste pipe in the ground heading to the SVP. then use a inline trap out of ground next to cylinder to run relief pipe into. the waste pipe MUST have a fall on it.

Being 40mm it'll be oversized so not risk of back pressure so long has there is a fall + the D1 and D2 measurements from the relief valve pipework install kit are followed.

 

[sturharv]

Thanks manortim

 

[sturharv]

Would the waste valve be within the slab i.e. under the insulation, or in the screed above the insulation?

 

[sturharv]

The D2 waste pipe will be after the waste valve, why would it not be acceptable to run in plastic?

Hepworth HepvO valves can be installed that way I think??

 

[sturharv]

failing that, don't bother with a PRV and cap them off

No way should you cap a PRV or the discharge pipes from unvented cylinder. D2 pipe should be run in copper not plastic and should not discharge into a plastic pipe.

should be fitted by a suitably qualified engineer

Have you any other ideas on how this is normally done?

 

[twgas]

d1 will connect to top of tundish, D2 will be ran in metal pipe at least one size larger than D1, it must fall for its entire length and terminate safely, outside.

 

[sturharv]

d1 will connect to top of tundish, D2 will be ran in metal pipe at least one size larger than D1, it must fall for its entire length and terminate safely, outside.

Thanks. Can the metal pipe run within the floor screed? or does it require a duct?