Just looking at the regs for discharge pipework, it seems that terminating the D2 pipework into a gully is preferable to leaving pipe open, but aimed back towards an exterior wall above ground like on a unvented CH system.
What other options are there?
Ta
Steve
I am sure it's not kosher but ours terminates under the floor. Mind you it is not the only thing not kosher despite the installation having a Gas Safe certificate, the boiler had been replaced a matter of a few months before we bought the house two years ago. Since then a service engineer pointed ou t several aspects of the installation not meeting the requirements of the r egs. that applied then and had not changed since. Likewise I always underst ood that the condensate pipe should terminate in a gully yet at my daughter s new build most of them spew out on the drives and hers onto what will be a public walkway. It seems that the regs. are free to be interpreted at wil l and I have little faith in Gas Safe as a regulatory authority.
Richard
I don't know but I have seen tundishes used internally to vent the pressure relief valve into a 28mm copper piped to a drain.
AJH
In my holiday (first floor) flat there is a built-in cupboard which houses the boiler and the unvented cylinder and the primary and DHW expansion vessels.
The cylinder's over pressure/temperature valve and the PRVs from both expansion vessels *all* discharge into a tundish - whose outlet pipe goes out through the wall and into the hopper which serves the kitchen sink and other waste pipes.
I've taken mine straight through the wall and tee'd into gutter downpipe on then onto the surface water soakaway. Not seen this done but as far as I can see it is compliant with the regs, works and can't freeze up (the boiler condensate is done the same way) and is neat and tidy.
The main requirement is to make sure that the discharge can't cause injury... should it open in anger on a "hot" discharge, then you could be dumping several gallons of near boiling water. So it needs to be somewhere it can't spray someone standing in the wrong place.
On my system it comes through a wall at low level (about 8" off the ground) and discharges straight down onto soil / grass.
It can go to a drain or a soakaway. Dropping onto a path however is not adequate, although alas not uncommon.
That is acceptable. The guide lines are here:
If the roof covering can take it, you can discharge onto a roof.
Owain
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