Fermentation or Pressure Change?

[JSBULL]

I have a new Spike 15 gallon conical with a glycol chiller attached. It resides in my Arkansas garage, which is about 85-90 degrees at the moment. Therefore, there is a cycle occuring where the temp goes from 74 to 76 to 74 to 76 etc.

I've done two SG tests on my recent brew (berliner) a couple of days apart and it appears that the SG has been stable at ~1.006. However, the blow-off tube from the conical is still bubbling periodically - every 5-10 seconds.

Why?

My hypothesis is that the temperature fluctuation due to the glycol system is fairly rapid and it might be causing pressure changes. Therefore, as it warms, pressure is released through the blow-off hose. If this is the case, then it's not new CO2 blowing off from the yeast, it's just pressure changes.

Is this a reasonable hypothesis? Any other thoughts?

 

[flars]

Very probable that it is due to temperature changes. Take another SG reading in 5 days. It can be difficult to see minor changes in SG if the readings are taken too close together.