Fireplaces, Heating Stoves, Flues and Chimneys - non-vented fireplace fire goes out

My non-vented fireplace, using propane, keeps shutting off after 40 seconds of running.

I vacummed out the fireplace and tested the furnace to see if something was wrong with the quality of propane and the fireplace still shut off after running for less than a minute.

Any ideas why?

I also, am debating on replacing this unit with a wood burner,
pellet stove or vented unit. Any suggestions?

My concerns with pellet = pellets selling out,
electric going out, electrical problems with components.
My concern with wood = labor, messiness, one year old touching it, allergies.
My concern with vented or non-vented unit = cost of propane in the future (which is better vented or non?)

I'm only guessing here but does it have a low O2 sensor? Maybe that is going bad?

IMO - I feel vented is always better because of the risk of carbon monoxide poisoning. I have a pellet stove and never had a problem with not getting pellets. I don't run mine 24/7 so a pallet (50 bags) lasts me all winter and costs about $240. As it stands right now I still have 20 bags left.

All gas fireplaces require annual servicing. Vent free fireplaces have additional safety sensors that need servicing and when these sensors are not properly cared for, it shuts down the fireplace.

Vent free- 99% efficient
Vented- 15% efficient
Pellet- no power no worky
Wood- new exercise program, chopping wood

Vent free can have carbon monoxide issues, just like any heating system, if improperly maintained and/or operated. Call a gas fireplace professional and get that unit serviced.

Since you have a chimney, partially open the flue about an inch. It helps in taking the smell and possibly CO out the flue pipe. I still get great heat without the smells of the ventless fireplace.

you need to know to brand of ventfree logs as there is a difference to how to co is detected, you may have a bad detector or your log may have knock something out of alingment, have a service tech check it out