Pretty sure now that there is nothing connected on the inside of the burner entry pipe after what you said. I undid the tee nut and cleaned out the pipe as best I could. I found the washer which is copper coloured and its difficult to see its there unless you crouch right down and shine a torch on it.Hi again
Thanks. I'm beginning to conclude that the handbook is misleading and that the tee is in fact referring to the one you mentioned on the outside of the pot - although I can't see how you could "lose the washer below any deposit"???
I'm hoping to get hold of someone at Esse tomorrow who can clarify this point (and maybe the other issue too). I'll update you when there is a development.
Anway, we lit the Esse and it is running as usual. The sweep is coming in a few days, so I'll get a chance to check her over.
What I have found is that I get a beautiful blue flame when the oil is turned up to Position 3 (quarter past the hour when viewed sideways), rather than Position 2.