ETS Sunscape 756 Making loud pulsing buzz

[manbeer]

Hi,

I have an 05 Sunscape 756 that i installed about 2 years ago and has been relatively trouble free. I once had an employee mention that it was making a noise and when i came to check it was fine. That was months ago

Today when fired up for the first time i heard the noise

It is a loud pulsing buzz that happens about every 2 seconds at a steady rate. It seems to be coming from BOTH of the external fan units mounted to the back. It's as if they are trying to start and unable. Am assuming that it has to be something internal as i doubt both motors would fail at the same time

If necessary i can post video. It's pretty freaky though. Sounds like an alarm in a power plant or something

Thanks in advance,
Chris

[tanu01]

Theres a 11 inch box fan inside the canopy, I had one go bad a few months ago.

[manbeer]

The problem stopped and the second session, the problem i see now is that when i turn the fan down it automatically seems to raise itself. The first person who used it mentioned that she turned the fan down all the way when she started it and that was when it happened. Could it be some sort of protection circuit for the fan?