bigboogieman
Member
I have an Anvil SS bucket fermenter, with the Anvil cooling system (pumping ice water through a coil), and a fermwrap, all hooked up to an Inkbird controller. This setup seems to do a good job of keeping fermentation temperatures within a couple of degrees F.
I just used this setup for the first time, and I noticed something I hadn't considered: when the heater kicks on, the contents of the fermenter expand, and air is expelled out of the airlock. So of course as it cools back down about 1-2 degrees F before the Inkbird kicks on again, the contents contract and room air starts getting sucked back in through the airlock.
When the yeast were active, this didn't seem to be a problem, because they were pushing out enough CO2 to overcome the suck-back. But what about when the yeast stop doing their thing? I like to leave the fermenter alone for a couple of weeks after the yeast are done. I disconnected the heating/cooling system once the yeast slowed down, for fear that I would end up oxygenating the beer. The ambient temperatures were getting down to about 63F. I would have rather kept the temperature stable the whole time, but I guess it probably doesn't matter that much after the yeast slow down?
Is this a problem I actually need to worry about? It will be worse in the summer as I would like to keep fermentation temperature around 68F (for US-05), and ambient gets up around 82F. How does everyone else without CO2 capabilities deal with the expansion/contraction cycles sucking in air?
I just used this setup for the first time, and I noticed something I hadn't considered: when the heater kicks on, the contents of the fermenter expand, and air is expelled out of the airlock. So of course as it cools back down about 1-2 degrees F before the Inkbird kicks on again, the contents contract and room air starts getting sucked back in through the airlock.
When the yeast were active, this didn't seem to be a problem, because they were pushing out enough CO2 to overcome the suck-back. But what about when the yeast stop doing their thing? I like to leave the fermenter alone for a couple of weeks after the yeast are done. I disconnected the heating/cooling system once the yeast slowed down, for fear that I would end up oxygenating the beer. The ambient temperatures were getting down to about 63F. I would have rather kept the temperature stable the whole time, but I guess it probably doesn't matter that much after the yeast slow down?
Is this a problem I actually need to worry about? It will be worse in the summer as I would like to keep fermentation temperature around 68F (for US-05), and ambient gets up around 82F. How does everyone else without CO2 capabilities deal with the expansion/contraction cycles sucking in air?