real loud noise suddenly..any help?

I have an Enviro EF5 evolution...stove has been great. Today out of the blue it started to make a little sound...then after a little while the noise got to be real loud. It only comes when you turn on the fan blower on the side of the stove to make the heat come out more. What would that be? Its to the point where its real loud. Like i said the stove only makes that sound when i turn the fan on. Any help would be appreciated.

Your convection blower needs to be cleaned and lubed. Should fix it right up. I recommend you do this once every ton to 2 tons max to keep it working at its peek.

Yup sounds like a heavy squirrel cage, clean it up.

A few years back I was on my way out to replace my blower, then stumble on this forum...

Original blower still pumping heat

Thanks guys appreciated the fast response!!