Can you fire an older A-series Paragon kiln on a 3-wire circuit?
The 4-wire system is required in the earlier Paragon A-series kilns because they use 4-way rotary switches. Around 1987, we converted to infinite control switches. That type requires a 3-wire system.
There are two elements wired to each 4-way rotary switch used on the A-series kilns. On LOW, both elements fire on 120 volts. On MEDIUM, only 1 element fires on 120 volts. On HIGH, both elements fire on 240 volts.
Since the kiln is actually 120/240 volt, it requires the neutral current-carrying wire. The 4th grounding wire is for safety.
Technically, our 4-wire kiln will operate on 3 wires, but it's not considered safe. Our UL Listing requires a 4-wire circuit.
Electric kilns that use infinite switches need only 2 current-carrying wires. The third is a grounding wire.