[Electronic M]

Originally Posted by bandersen

Ah, nuts. The transient suppression devices suggested for 3KP4s only go down to about 6.8 volts.

http://www.littelfuse.com/data/en/da...iode_1.5ke.pdf

IIRC form a class I took a couple of years ago those AC transient suppressors are just two Zener diodes diodes in series with either the anodes or cathodes connected together....You could probably make your own with two Zeners each of the max voltage you want across the heater and a suitable current rating.