I recently purchased a new Mathmos lamp through a eBay reseller who said he acquired it from the Mathmos factory in the UK. He shipped it to me in the United States. It came in what looked like entirely authentic factory packaging. The model is 'Mathmos Heritage Astro Lava Lamp Copper Finish with Red Wax in Purple Liquid'.

Twice I've had it plugged in for over 8 hours and the lava never moves from the bottom of the lamp. The bulb is working and appears to be heating.

I made sure the room was at a good temperature (>20 C). The coil appears to be well-positioned on the very bottom of the bottle.

Note that I'm using an adapter so that I can plug it into an American electrical outlet.

Note also that I live near Chicago and that the unit was shipped in below freezing temperatures. I did not attempt to turn it on for 24 hours after I took it in off my step. I'd read somewhere in one of these forums on this site before I purchased that prolonged exposure to cold even before first use can permanently damage the wax. My eBay seller said he had never heard of that problem so I asked him to go ahead and ship to me.

I'm hoping that my brand new unit is not defective. Can anyone suggest some things I can try to get the lava flowing before I pursue getting it replaced as a defective unit.