We all know the OWB's make enough creosote to sell the stuff. But what's the best way to burn it out of the firebox? I have heard cardboard will burn really hot really fast to burn it out. But I'm a little concerned about this, so I thought I'd ask. I have been trying to let the water temps run down a bit and letting it burn flat out for add along as the aquastat will allow. It does ok but, Is there any other way to burn it out safely?