Low temp fluctuations

[Charlie]

Lager temps? I read you loud and clear.

Oddly enough it was low temps that caused me to get my first fermentation chamber. It was your basic $50.00 Craigslist top-mount fridge (white and about 17 cu/ft). I scrapped the shelves and drawers and built a platform for the fermentors (carboys at that time). Cooling was supplied by the fridge itself and heat by the aforementioned ceramic heater. I only had a one stage controller (Ranco STC-001). It would do heating and cooling, but only one at a time. I wired it through a project box with a switch that directed power to either the refrigeration or heating.

A few years later it died and I got another Craigslist fridge and did the same thing. The problem was that it would only hold two 5 gallon fermentors, so I built a fermentation cabinet using plywood and 3/4" foam insulation, and the old fermentation chamber became my kegerator. The new FC will hold four 5 gallon fermentors (two up, two down), and works like a charm. The doors are 1/2 inch plexiglass with foam seals. Cooling is with a tiny window AC with the thermostat disabled (it will hit 45F), and I'm still using the ceramic heater. The controller is a two stage Ranco (ETC-002 I think). Your STC-1000 is superior to the Ranco because it will do fractional degrees.

Charlie

[Ozwald]

What's your gravity at currently?
it got in a 3 week time span was -17F. And that was just briefly one afternoon. It was between -22F & -35F most of the time. One night it got down to -49F. I actually had to put on a coat.

Ah, lagering temps

[NateBrews]

Lager temps? I read you loud and clear.
The new FC will hold four 5 gallon fermentors (two up, two down), and works like a charm.

Charlie

So I have the college fridge with a 2" insulation box built onto the front of it with an STC-1000 and a heating pad and circulator fan. I have a shelf that I built that sits in it so I can put 2 carboys, one on top and one on bottom. I have noticed a systemic 2 degree F difference between the top carboy and the bottom one (top is warmer). I always have it setup to control based on the temperature of the bottom one, and just live with the temperature of the one on the top (I have another sensor on that monitoring the temperature so I at least know that it is where I expect it to be).

Do you see the same sort of consistent difference in temperature between the top and bottom ones fermentors? Also, are you just controlling the ambient temperature or do you monitor one of the fermentors?

[humpadilo]

If it were me, I would start to bump the temps up a bit after 1 week of fermentation to keep the yeast active and happy so they are sure to finish out your fermentation. Be sure to give this beer at least 3-4 weeks total time (more like 4) in order to totally finish fermenting and clean up after itself (condition) prior to packaging.

It's been almost two weeks since brew day and I got a heat lamp in the fermenter (chest freezer) a few days ago, so it is pretty steady at about 68 now. I guess I should bring it up to 70? I was planning on keeping it in the fermenter about three weeks and then transferring it to a secondary for about 2 months before I bottle it. Hopefully I can keep the bottles around for a very long time. I made this barley wine in hopes of having it after a year or two.

[NateBrews]

If things are almost done I would definitely raise the temp up a few degrees to make sure that you get full attenuation and the yeast clean up after themselves.

[Ozwald]

If things are almost done I would definitely raise the temp up a few degrees to make sure that you get full attenuation and the yeast clean up after themselves.

+1, but I would do a gravity reading first instead of assume just based on time.

[brewinhard]

And no need to rack to secondary. Leaving the beer on the yeast will allow it clean up properly. I would leave it for 4 weeks total and give the yeast time to drop out and clear up the batch a bit first prior to bottling.

PS - When you bottle, I would highly recommend adding back 1/2 packet (2.5g as these packets come in 5g) or so of rehydrated dry champagne yeast to help speed up and ensure proper bottle carbonation. I like Lalvin EC-1118 for this as it costs about $1 and is low pH tolerant as well as alcohol tolerant. This strain at this point in packaging will NOT affect any flavors you have worked so hard to produce and it will NOT ferment your beer any further except for the priming sugar added.

[humpadilo]

[/quote]+1, but I would do a gravity reading first instead of assume just based on time.[/quote]

I just checked the gravity and it looks like it is trucking right along. It is now at 1.018 after 13 days. The OG was 1.110. So I'm gonna raise the temp to about 70(?) to see if I can't drop it a bit more. If it doesn't drop I am good with that FG. I'm planning on leaving it on the yeast cake for about two more weeks. I want to transfer it to a secondary just because I'm not ready to bottle and I will probably leave it in my closet (that stays pretty constant at about 70-72) for a month or two.