"Vass" wrote in message
...
prob stupid Q, but if you dont know, you don't know
The drain plug I'm putting into my CH system is Brass
its 15mm diameter, can I solder to it?

s'ok
just read Andy's comment from earlier

"Taking out the centre component with the seal is a good idea. a) there
is less to heat and b) it avoids melting the seal.
Buying a good quality one and cleaning it well is good.
Apply flux and then heat starting at the outer end of the drain cock brass
component and moving towards the copper fitting. This reduces conduction of
heat away and boiling off of all the flux."

Ta anyway
--
Vass