So dlloyd, you're suggesting to put the fan and the sensor and the 4k7+LED all in parallel? That will be fine for the sensor, and will get me the low from the output I'm looking for, but will cause my fan to blow more than desired, but I guess I could also put a resistor in front of it as well?
The fan was not previously connected across 24v - it was connected in parallel with the sensor but in series with the LED, so the fan was only seeing 10v.
... I want the LED and fan to both always be on, no change when sensor triggers or not ...
Did my replay of your suggested zener configuration make sense with respect to how it would work with the trigger low board sensor?