I have a problem with one of my Mathmos Jet's. It has been flowing fine for many years and it seems to have stopped flowing for some reason. After about an hour or so it starts to flow like normal, then it just stops!! The lava collects at the bottom of the vase and bulges up like it about to start flowing but just stays there.
On closer inspection the lava appears to rise slightly above the metal coil in the bottom of the vase. Do you think this could be the problem as the lava isn't getting heated properly?