A Relay May Be Stuck Shut
- All computerized kilns use relays to cycle the power on and off to the kiln sections.
- If one of those relays sticks shut, power will go to the kiln all the time.
- All L&L Kilns relays and contactors are of a type called "normally open", meaning when there is no power coming to their electro-magnetic coil their electric contacts are open and not allowing power through.
- If a relay overheats, its contacts they can weld themselves shut causing power to pass through them even when the kiln is off.
How to Tell For Sure
- When the kiln is cold, keep the toggle switch off and plug in the kiln.
- Can you hear the electricity hum in the elements?
- Wait a minute, can you feel heat from any of the elements? If so, which ones? (be careful not to actually touch them).
- Whichever elements come on, replace that section's relay.