Roasting with the PID

Since I have wried the PID into roaster, I have roasted twice, and just one small batch at a time.
Due to the fact that both gas lines had to be re-routed and modified, and I have been dealing with many leaky gas lines.
The reason for the new gas lines was because I needed to maintain a burning flame on the main burner.
When the PID pulses on and off as it nears the set point, the burner needs to be already lit.

During the first roast, I did have a flare up on the left side where the gas line enter for the main burner, only scorching some electrical wires, but I quickly turned off the main valves and power to the PID. After the flame went out, not wanting to ruin a batch of coffee, I quickly resumed roasting. The Roast was lite.

During the second roast, I located another leak, this one was because I had a 3/8 flare fitting attached to non-flare. This roast turned out better as I didn't need to have the gas pressure set to higher than normal.
But I  did notice that even though the PID turned off, the gas valve was not disengaging properly.
During preliminary  testing using a neon bulb, I notice current was still running through the bulb even when the PID s output was off.
I wonder it that small amount of juice could keep the valve turned on after the initial actuation.