Heating a keezer/fermentation chamber: best options?

[AntDoctor]

I am using my custom-made keezer as a temperature-controlled fermentation chamber, at least during the holidays. I was checking the temp while I was away (it sends the temperature info to a server via the Wi-Fi) and I noticed that it wasn't oscillating or even reaching the minimum temperature I set for it. Living in Phoenix, AZ, it took me a while to realize what was going on: my house was actually too cold! Haha, living in "The Valley of the Sun," cold is not something I am very used to. My current batch of beer might be ruined, but I guess I need to figure out how to add some heat to the keezer.

What option do people think is best? Since I ferment in kegs, my temp probes measure the air temperature inside the keezer, not the actual temperature of the wort. So I won't be able to use brewbelts or carboy-heaters with precise temperature control. Should I just throw a heating pad in the corner of the keezer to heat the ambient air or something?
I know some people do a dual setup, with one half of the keezer for serving beer and the other insulated half for fermenting at higher temperatures. Although this is cool, I'm fine keeping everything at a higher temp while fermenting. Just curious about how other people solve this problem.

 

[Knightshade]

I'm not sure how others would accomplish this via a dual system, and honestly have trouble visualizing your setup based on what you've described. I keep my kegerator at 34, and I just upped a batch of beer that I dry hopped this morning up to 70 for the last 4 days of its ferment. It has been in the 50s or so in my garage the past couple of weeks. Seems that either would suffer if I tried to do both in one box?

As far as the temp prob thing, the Inkbird controller that I use has a temperature offset. I tape the probe to the outside of my fermenter and cover it with a ghetto sleeve I cut and sewed together from a beer koozie. It is only plastic, but I set it to a -1F difference to ensure that the core of the wort was closer to the temp I want, not just the surface closest to the outside. I think I may have had it to -2.4F or something when I was fermenting in a stainless bucket. Had some tuning experiments when I set it all up. Also set up a small fan to help circulate the air. I use a seedling mat, some others utilize small space heaters to great effect.

 

[gromitdj]

Personally, I think that controlling your fermentation temperature by measuring the air temperature is the wrong approach. Because you ferment in kegs, I would recommend fastening the probe to the side of the fermentation vessel and insulating it from ambient as much as possibe as @Knightshade recommends.

As for a recommended heater, anything that provides enough btu's without being overpowering would work. I highly recommend running a circulation fan at all times and in my ferment chamber I run a PC fan 24/7. For heat I use a 100 watt ceramic reptile heater wired through a dimmer so that I can turn it down even further. My setup (Fermentrack and BrewPi Remix) has a minmum run time for the heating and anything larger will overshoot. Which makes the cooling come on to compensate. And that messes with the pretty graphs I like to look at.

 

[InspectorJon]

See this thread:
https://www.homebrewtalk.com/threads/fermentation-chamber-heater.687168/
I just got one of These. I got the 40 watt bulb. You can get the ceramic base to screw the bulb into at any good hardware store for a few dollars.

 

[AntDoctor]

Nice! I have a ceramic heater that I got for my chickens that's not being used. I didn't think of using that!

The air-circulating fan I was using broke, but that's easy to fix. I've also used the tape-and-insulation approach to attaching temp probes in the past, and if I only have one keg I'm working on at a time, why not, I guess?

 

[day_trippr]

fwiw, I use 40w ceramic "bulbs" in cheap porcelain fixtures behind small pc fans in each of my 17cf fermentation fridges. The do only have to deal with mid-50s ambient worst case/dead of a really cold winter and more typically see low 60s, but they do work great, with a slow enough heat ramp to not cause ping-ponging...

Cheers!