From the bomb cyclone that many experienced last week to colder than average temps across Texas, this unusual winter weather sweeping across North America is causing havoc for everyone! So, with snow swirling outside and the wind howling, this question frequently comes to mind... can you fire a kiln in an unheated basement, shed or garage?
A few years ago, Arnold Howard from Paragon told us about a customer who tried to fire a digital kiln in a garage where the temperature was 30°F. The digital controller display locked at 32 degrees, and she could not clear it. After the weather warmed up, the kiln started working again.
Most digital controllers can register temperatures of –300°F; however, the circuit boards are designed to operate in temperatures no colder than 32°F. Temperatures lower than that can cause the controllers to malfunction. For example, the TCR message ordinarily means the thermocouple leads are reversed, but it can also appear when the thermocouple inside the kiln is much colder than the controller circuit board.
In spite of this, it's definitely possible to store and fire a kiln in an unheated building in cold or freezing weather. Gail had her larger kilns in the garage for years prior to building her new studio. For storage, you must make an extra effort to keep moisture, such as the air from a dryer vent, away from the kiln to avoid the formation of frost on the metal jacket. When it comes to firing, it's important to first raise the room or ambient temperature to 32°F. This can easily be done with am inexpensive space heater. Just place it within a couple of feet of the control panel before you start your kiln and let it run for an hour or so. After you turn on the kiln and it begins to heat, you can turn off the space heater.
Moisture that the firebricks have absorbed from humidity will burn off harmlessly so long as the kiln is vented. Keep the lid in the vented position until steam no longer fogs a mirror, or run a motorized downdraft vent.