draining my CH system - combi boiler

[mickyk]

please help?

I want to (bravely) try to relocate a few CH pipes in my bathroom. Obviously I need to drain the CH system first and this is where i am stuck. At my old house there was a pipe outside the property and i simply unscrewed a brass plug and this drained the system. I can't find an equivalent in this new place. The combi is on the second floor of my property and serves the second and third floor. A separate combi serves the ground floor. I would expect to find a drain somewhere on the second floor but can find nothing and i can't see any pipes on the outside of the property. The nearest thing i can see is a pipe in the bathroom that is tapped of the CH pipes. It is 15m and just has a brass screw plug on the end and does nothing / goes nowhere. It doesn't look like the logical place to have the drain pipe but then again I am a complete novice so wouldn't know any better. Could this be the drain and if so, how do i ensure i don't flood downstairs as i unscrew?

Any advice welcomed

thnx

 

[ChrisR]

PIck a convenient rad, turn its valves off and drain it by undoing a union a bit. You need a flattish bowl. Then remove the rad and you 'll be able to put a hose on the union. That will only get water levels down to that level of course, so a water-capable vac is handy thereafter to suck thewater out (£35, wickes, or hire/borrow one).

If you don't know the system assume it has no inhibitor until you see evidence to the contrary, so drain all the rads and add some when refilling.

 

[brumylad]

if you are going to replace those pipes in the bathroom you could drain the system by cuting into them using one of those awful self tapping DIY washing machine taps. Insert a propper drain off valve when you re pipe.

 

[ChrisR]

Sure you can use them, but the little disc they cut out can go round the system and cause havoc. If you stop screwing them in as soon as water starts to come out, the disc doesn't get cut free.

You can do that on a rad tail anywhere, as long as you replace it when you've done all you need, with a tee and proper drain cock.

 

[brumylad]

Good tip Chris, I stand corrected

 

[mickyk]

ok thnx -I'll give it a go! fingers crossed.