Question: Re: Anthracite Burning Hi there, I have a Stanley burner and I am starting to use anthracite. I find it has greater heat output than standard coal but after a while compacts and gives less heat than it initially did burning slower, is there a way I can keep it burning more vigorously? I have increased the flue. Should I mix it with other fuels e.g. cold etc. Answer: You should not mix it with other fuels. The ash is probably building up and slowing down the burn. The most important thing to do is to properly de-ash. In many stoves this requires running a poker over the grates (if there is access to this area) and then shaking the grates. DO NOT POKE THE FIRE FROM ABOVE. If you have a weak draft, the ash buildup will quickly slow down the air flow through the coal and therefore the heat output.