On Thu, 27 Dec 2007 17:46:16 -0600, Ignoramus7897
wrote:

On 2007-12-27, wrote:
I have a ventless setup in my Garage. I use a shop fan (Air King) to
circulate the air on low.

I tried a ventless kerosene heater (same area) and could not use it
due to headaches. I returned it.

i

The instructions for those say to leave the garage door open at least
a couple of inches. No doubt you did, right? There is significant
risk of carbon monoxide with any non-vented combustion heater.