Not sure what I'm doing wrong with the Zippos. I have four. Two I tried several years ago and had no luck with them. Yesterday, I filled two unused ones according to the instructions. Two full fill-containers of fresh lighter fluid for first-time use. One full fill-container thereafter, so I used two full fill-containers to fuel each of these unused warmers.

One stayed lit and one went out, probably within ten or fifteen minutes. The one that stayed lit barely ever got warm. I let it go lit in a safe place overnight, and it was still barely warm to the touch this morning.

The one Zippo out of four that I own stayed lit, but the lack of warmth wouldn't even make it worth bothering with. It's barely perceptible.