The picture should be rotated 9o degrees to the right!
The elbow with the isolator on has a threaded union at the one end and the other seems to have a pressed in pipe which then has a union on the far end of the bit of pipe.
It looks to me to be a specific part made for that boiler (ravenheat crap)
Could I just get an isolator elbow with threaded unions on both ends and make up the bit of pipe to suit in an attempt to replace it?
Or just a plain elbow and pipework with a normal straight isolator below the original one may be easier?
If it makes and difference the pipe in question has the filler loop attached to it just out of the shot.
My next question is going to have to be on how to drain down and re pressurise the boiler when working on it!!!
isolator
[Edited on 28/3/13 by locoboy]