The flashing kits tend to crack/melt when the stove is operating over temperature, they work to around 300 degrees, but it can sometimes get above this at the flue flashing if it is a bit too well charged.

The only solution is to keep the fuel down a little as the flashing kit acts as the 'fuse' between canvas and flue pipe.

We are afraid we can't warranty the flashing kits against this, because its correct operation is so dependant on the stoves running temperature.

A small thermometer can be really useful just to help regulate the temp.