Fermenting Oak Pellets

[Oak]

So i have been fermenting oak pellets for about 2 years or so, but for some reason they aren't generating as much heat for me these days. The temp is around 23-25C, so i know it's not the temp problem. Last time i put in too much flour so it screwed up the sub pretty bad, and i tried adding more yeast, but the temp didn't change at all. Am i doing something wrong?

[Shade of Eclipse]

You can try something other than flour since it's so rapidly broken down. Flour is mostly starch and yeast can very rapidly break it down. This rapid breakdown means that it'll initially have a high temperature and lots of carbon dioxide output and then it dramatically drops before you can cultivate the microbial fauna required to start the process of breaking down wood.

 

It's possible the temperature and carbon dioxide levels are high enough to kill the microbes you're trying to ferment the substrate with, but it might just be that the process uses up all its fuel too quickly and fermentation ceases to continue and the wood remains untouched and unsuitable for continuing fermentation. You can try using more complex sources of carbohydrates and see if they work for you. I use wheat or rice bran.

[Ratmosphere]

Does the temperature need to be at 70 degrees fahrenheit or above year round for the wood to decompose?

[Shade of Eclipse]

Warmer temperatures cause faster decomposition, but wood-feeding organisms can produce enzymes that break down wood in cooler temperatures as well if they are adapted to cooler temperatures.
You will also find that during the process of decomposition, heat is produced and the mixture should be warmer than its surroundings. You can consider fermentation complete when the substrate no longer produces its own heat.