Hi,

I'm currently preparing to have my current domestic heating/plumbing
system replaced and will be using a combi boiler. I have almost
everything sorted out, but I can't find any info on what to do with
the relief valve pipework.

Can I use the existing hot water tank vent pipework for this relief,
or do I have to run new pipework direct into a drain and if so, can I
use the existing bathroom drainage system to vent into?

Many thanks in advance for your advice.
--
Andy