Concerning the spalling a.k.a explosions any moisture becomes steam at 212 degrees at sea level. Moisture/water expand 17 times its volumn when turning to steam.
Water actually expands 1600 times its volume when turning to steam.
Cold weather is only an issue if you have a digital controller. They'll usually work fine a bit below freezing, but they can't read below 0 degrees F. If it's behaving oddly due to the cold, simply put a small space heater near it for a while before turning it on. Once the kiln gets hot enough it will keep itself warm.
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