Ron, glad to hear you got yours started but this is a problem with the thermacells. This is from the Q&A section of the thermacell web site:
Q: My ThermaCELL device is not working correctly at high elevations. What can I do?
A: Unfortunately, most ThermaCELL mosquito appliances and lanterns will not work well at higher elevations. At altitudes above 4,500 feet (above sea level), most units become difficult to start and run. The lower air density causes the problem. If you are having trouble using your ThermaCELL at high elevation, it is probably not a defective appliance, but just a limitation of the product at high elevation.
If you plan to use your ThermaCELL only at high elevations, you may be interested in the Mini Mosquito Repellent Lantern – 2006 Model. It functions well at higher altitudes, but must be lit with a match.
If you are affected by this altitude product limitation and have no use for your ThermaCELL at lower elevations, you may return the product for a full refund. Email customerservice@thermacell.net or call toll free 1-866-753-3837 for instructions
Couldn't use mine this year on my elk hunt, But it works great in the desert for deer!
Hope this helps,
Matt