Temperature control options

I have made my last 3 batches in my new fermentation chamber. It's a chest freezer with a Control Logic 2 stage temperature controller. Wasn't sure how much the elements were going to cycle, and didn't want to short cycle anything, so I elected to leave each stage at it its default 3 degree temp swing. I set both stages to the desired temp, which I usually select at the low end of the yeast range ( IE 68F-74F, set at 70F)

What that means is the heating element would come on if the fermenter goes below 67, and the cooling element would come on if the temp went above 73. Should I tighten that range to 1 or 2 degrees? 0 degrees? FWIW, the controller does have a short cycle override on the cooling setpoint that prevents the compressor from coming on until 5 minutes after it shuts off. Thoughts and reasons would be appreciated.

Unless you have the temp probe in the wort, the reading will not be exactly accurate. The temperature fluctuation inside the beer is much less than in ambient air or on the side of the fermenter. I think once temperatures stabalize after you put the fermenter in, it wouldn't fluctuate that much and the controller short cycle override will be more than enough to protect your chamber and keep it within 2 degrees.

I use a 4 degree range, 2 below, 2 above, and the compressor comes on maybe once an hour.

Short cycling the heater is no problem if you can set that one tighter (1F).

I'd also try 1F on the cooling side if you get the probe trapped under insulation on your bucket/carboy wall. That set-up shouldn't cycle much at all and you can adjust to 2F if based on experience.

I had active fermentation in my freezer set to cooling mode (65F setpoint, 62F ambient) with 1F differential (A419 controller) and the probe insulated on the carboy with about a cooling cycle per day. I used a 4W heater constantly on in the freezer to overcome cooler ambients than the set-point. The heater is (2) 10w 10ohm resisters in series powered with a 9V regulated DC wall wort power supply. I also have a PC fan constantly circulating air using a 6W DC unregulated power supply (8W actual power to the fan).

Cycling is going to a bigger concern at lower set-points. But the key is to always insulate over the proble on the wall of the bucket/carboy when cooling.

After active fermenation is complete and I want to control to a temperature above the ambient, I've control by heating the air temperature inside the freezer (probe removed from insulation and wall of bucket/carboy) with a 1F differential with an 8W heater. The heater may cycle hourly with setpoints 8F-10F over the ambient, but that's ok and the actual beer temperature may only vary 0.3F. I learned this for bottle conditioning when the freezer was empty.

I insulated the probe by carving out a recess in a piece of rigid insulation. Duct the entire thing near the bottom of the bucket, brew belt just below the top ring.

I think you will get a better answer to your question if you mention where your temperature probe is located. Some just have it in the air, others use a thermowell, and some tape it to the side of their carboy covering it with some sort of insulation. It get the feeling that the majority do the latter.