how do I drain down a combi boiler All aspects of plumbing questions and answers, help, tips and information

[mrg]

I've got a leak on a rad valve and need to replace it but I obviously need to drain down the system first. I had a quick look before I left for work this morning but couldn't see anything that looked like it might be a drain down tap or similar on the boiler - what do they look like? - its a brittony / chaffateaux boiler I think