P68 fire going out

[newf lover]

This has happened 3 times in the past 3 days. The fire starts up fine, goes for 12+ hours, then by the time I get home from work, the fire has gone out. The stove is a P68, second year of burning. First 2 times it was in room temp mode, feed rate 3, temp around 70. One time there was no error code, second time, 5 blinks which means igniter fails to light within a certain amount of time. Last night I put it on stove mode, auto, feed rate 4, the other dial 2.5. It was my understanding the fire is not supposed to go out. I got home from work, the house was 63, and there was no fire, but the fan was still running. I opened the hopper, it was 3/4 of the way full. I closed the hopper and the fan went off, no error code.
Yesterday, thinking maybe the stove was dirty, I did a full cleaning, including the leaf blower trick. I did not clean out the feeder body yesterday, but did today. There was a fair amount of fines there, but I doubt that's the problem. I vacuumed the fines out, put the stove on room temp 75, feed rate 4, and turned it on. It's burning fine, but like I said, it always is fine for quite awhile.
The stove is obviously still under warranty, and I will call the dealer assuming it does the same thing tomorrow, but anyone have ideas why this happened? On my way to take the dog to the groomer, so if anyone responds, it's not that I'm ignoring you. Thanks.

 

[DAKSY]

In your complete cleaning did you clean ALL the burn pot holes?
Did you remove the wing screws & brush the igniter with a dry, soft-bristle paint brush?
Did you then vacuum out the crud from the igniter cavity?

 

[HEMI]

clean the ESP yet?

 

[summit]

sounds like a bridging issue, or a sticky air intake flapper, maybe a hopper lid that was not shut all the way....

 

[newf lover]

DAKSY, thanks, I did clean out and vacuum the whole igniter area. I thought that the problem was the igniter, but since it shut down in stove mode, I am assuming it's not the igniter since it's supposed to keep on running until it runs out of pellets, and it's not dependent on the igniter to fire it back up.
I don't think it's a bridging issue because today i just vacuumed out the fines in the feeder body, fired her up, and it's been burning since. I never touched the hopper except to open it and look inside. I don't know about the hopper lid. My daughter was home and I suppose she could have not closed it properly. I guess I'll have to wait and see what happens tomorrow while I'm home. Thanks.
Now about the ESP probe.... When I cleaned it, I used one of those brushes like you would use to clean under the refrigerator, and it looked pretty clean to me. To be honest, everyone says it's easy to take it out and clean it, but i couldn't figure out how to do that. When I took off the side panel on the right as you face the stove to clean the feeder body, I looked to see if I could see where the ESP was connected, and I couldn't figure it out. I was in a hurry, but I'll give it another shot tomorrow.
I knew people would have good suggestions. Definitely a couple possible causes here. We'll see what happens tomorrow as i plan on being home most of the day. My bet is on the ESP or college aged daughter not closing the lid properly. Thanks everyone.