The Heart of an Electric Kiln
Electric kilns heat up using elements: coils or strips of resistance wire (usually kanthal or nichrome alloy) that glow red-hot when electricity passes through them. Elements are recessed into grooves in the kiln's firebrick walls and run in parallel circuits. Every electric kiln has multiple elements, and they are one of the most commonly replaced consumable parts in studio pottery.
How Elements Fail
Elements do not last forever. Over time, repeated heating and cooling causes the metal to become brittle. Eventually:
- An element develops a crack or break, interrupting the circuit.
- The kiln fires unevenly: areas near the broken element are cooler than the rest.
- In extreme cases, the kiln cannot reach temperature at all.
Signs of a failing element:
- Firings taking longer than usual to reach temperature.
- Uneven firing results: some pots underfired, some correctly fired in the same load.
- Visible breaks or melted spots in the coils when you inspect the element grooves.
How Often to Replace
Element lifespan varies widely. Bisque-heavy studios may replace elements every 1-2 years. Glaze firings (which reach higher temperatures) wear elements faster. Many potters keep a firing log: if the time to reach temperature has increased by more than 20-30%, it is time to inspect the elements.
The Bigger Picture
The resistance wire used in electric kiln elements is typically made from Kanthal, a ferritic iron-chromium-aluminium alloy designed to withstand repeated heating to temperatures above 1300°C. Understanding how these elements interact with the refractory brick lining of the kiln helps explain why element replacement is the most common maintenance task in any electric kiln studio.
Preventive Maintenance Habits
- Vacuum element grooves gently between firing cycles to reduce debris buildup.
- Inspect peephole cones and firing curves together; slower climb with normal cones can indicate element wear.
- Check lid and door seals, because heat loss increases element strain.
Pro Tip
Replace full element sets when wear is widespread. Mixed old and new elements can produce uneven heating profiles.
