Exhaust Fan w/Ventilation louvres

[Fey_Wrangler114]

I'm not an electrician, but I do electrical tasks for my employer. Hello underfunded maintenance department.

I'm currently troubleshooting an exhaust ventilation fan system that's powered via a contactor, with vent louvers (the things that open/close to seal the vent or unseal it) that automatically open when the fans kick on.

The louvers are opening and the contactor is functioning but both fans, left and right, are not turning on. Visually verified by taking the ducting off the top and seeing the plastic rotor not turning.

What might be the issue? The wiring hasn't changed since install.

 

[westward10]

If they are both not functioning then it sounds like a supply issue. Just because the contactor is energised it does not mean all is well.