Just where is all this moisture coming from?

[cleverdick]

OK, I'm on the first serious day of curing. I have an Ephrem 2061 pre-cast dome, so no mortar joints to worry about. It sits on a bed of lean mortar (as per manufacturer's instructions), which is on a layer of calcium silicate board above a 1" layer of floor leveller. The dome is covered in ceramic blanket. Now, it has sat there for months before the first firing, always kept dry, and yet the blanket is now seriously hot and damp. I have not taken the temperature of the floor beyond 200c. There are also some small (hopefully superficial!) cracks on the top of the dome. I'm glad I checked before adding more insulation over the top, but I can't believe that after so long there was so much moisture locked in. Then again, the climate can be pretty damp here...

[GianniFocaccia]

I'll bet its the constant dampness that's made the oven moist and after a couple more curing fires you'll be good to go.