Hi, Moving on from my previous post, I've solved the issue of the fumes coming from the radiator but I now have another problem. After lighting the mantle glows red as it should and I have nice blue flames coming out of the burner with a good heat output. After a few minutes the blue flames seem to disappear and a blue halo appears around the mantle and the mantle no longer burns red and heat output has fallen significantly. I assume it is either a problem with the vapouriser or the burner. The top part of the burner I can revolve around on its axis as in that I cannot tighten it to the lower part of the burner although it does not feel loose. This is the only R55 I have so I don't know if that is normal. I have a R1 and I don't recall that occurring (I can't check as it is on loan to a friend). Are the burners interchangeable? Any advice much appreciated as I've no idea!