Raddling solinoid

[Gashmore]

Running a CNC4PC relay board with Mach3. I am using one of the triacs to control peripherals like dust collector, air for a vortex cold gun and solder paste dispenser depending on the job. The air solenoid is 110V and works fine. The dust collector relay is 24VAC and will not operate. The solder dispenser solenoid is 36VAC and when the solenoid is activated it cycles rapidly. If I wire through a 110V mechanical relay they work fine but a PCB board might require 1,000 or more cycles so a mechanical relay may not last very long.

Will those triacs not work on low voltages?

[Al_The_Man]

It is probably affecting the Triac firing voltage by lowering the gate current, as this is a function of the output supply voltage.
Al.