Hi Richard,
As O2 levels drop Catalytic heaters DO produce CO and unlike a blue flame do not self extinguish.
It is not safe to use an unvented combustion heater.
richardcoxid wrote:
Catalytic heater- Olympic Wave 3 (3,000BTU max), Wave 6 (6,000BTU max), Wave 8 (8,000BTU max) and others, Radiant Heater.
No open blue flame, however during operation the "pad" is orange hot! DOES NOT PRODUCE CO however to support the catalytic action they DO consume O2, 99% plus heat efficient. A small open flame is used only when starting the catalytic action. They will also KILL you (from lack of O2) if not vented properly (see above about cracked open windows) Dust is the worst enemy of the Platinum pad, keep covered when not in use.