I have a pizza stone that I've had for years... it's outlasted 3 different ovens.
My ovens (all electric) have gotten progressively better. I now have a KitchenAid dual-fuel double oven.
I love the oven, but my pizza stone no longer seems to get as hot as it used to!
I heat the stone for at least an hour in a 500 degree oven. But while this method always produced brown crispy bottom crusts on breads and pizza, now I only get pale, tender crusts.
The oven does get piping hot: Bread cooked in cast-iron dutch ovens turns out perfectly.
I thought I had the problem figured out: this is the first oven I've ever had that has a fan (or at least, I've never noticed the fan in the others). I thought maybe the fan was cooling the surface of the stone. But I tried it in the upper oven, where the fan doesn't seem so evident, and it didn't work any better.
Anyone have any ideas?