St. Croix SCF 050 buzzing noise

[mithesaint]

I've been running my SCF on a straight corn diet for about a month and a half now, and it's been working fine.

This morning, when I went to check on it, it was making this weird buzzing sound. It almost sounded like some sort of alarm. The sound was coming from somewhere on the back side of the unit. It would buzz for 3-4 seconds, then be off for 3-4 seconds. Then on, then off. It was loud enough to hear from a few feet away. According to the manual, all safety alarms will cause a blinking of the control board or shut down of the unit, and neither of these was happening.

It was burning fine at the time, no problems there. I was burning on level 4 (of 5) at the time. The only thing I can come up with is maybe it was the auger? I've heard plenty of auger squeals on my CPM, and it's definitely not a squeal. It's much closer to an electronic buzz than a squeal. I tried to watch and see if it matched up to the auger cycling, but the corn drops so quickly that I can't see it through the flame in the burn pot.

I hit the off button, and it immediately stopped. Will let it cycle down and then try to restart and see.

Thoughts?

 

[SmokeyTheBear]

mithesaint thinking hurts do we hafta?

Does it sound like a switch or relay chattering?

You might want to apply hand pressure to various metal panels on the stove shell be careful wear gloves to see if the stove has started any of them vibrating. I placed a small weight on my hopper lid and some strategically placed gasket material to silence most of the chatter that the stove was producing.

 

[Arti]

Sounds like the Auger motor. Everything is solid state / no relays in this furnace.
It could need cleaning or it could be a loose mounting bracket, it is easy to observe it with the back access panel removed. Also the light above the on off switch will light up when feeding pellets. see if the buzzing is at the same time the light is on.

 

[SmokeyTheBear]

I beg to differ on the all solid state.

The system diagrams show mechanical devices some of which have been known to chatter.

 

[mithesaint]

It's the auger. Once I shut it down and restarted it, it was easy to tell it was the auger making the noise. All the noise from the 800 CFM blower obscured it the first time. Good thing I just filled the hopper...

I had noticed that it wasn't producing quite as much heat over the last day or two, and had just figured that this particular bit of corn wasn't as good. Maybe it was the auger plugging up or coming loose all along.

Arti, do you burn corn? If so, do you clean it?

 

[Bioburner]

I clean the corn for fines and larger cob pieces. Cob pieces to large cram into the feed augers and fines blow out and make a mess in the Bixby. Arti, Sounds like you have the stove on high