suorangeguy
Well-Known Member
This is my first post of a brewing idea I haven’t seen elsewhere. If anyone else using something simpler please let me know. I am happy to answer any questions.
In an effort to lose some weight I have cut down my brewing to 3-gallon specialty batches. So now I have lots of five gallon kegs that aren't getting much use. I decided I would like to turn some of them into 3 to 3.5-gallon batch fermenters. With a shortened dip tube, I can take samples and transfer with no oxygen exposure. Using the gas post I can add a blow off tube or a spunding valve to experiment with fermentation under pressure. For temperature control I wanted to add a thermowell to the lid. I know with a stainless vessel many people just tape the probe to the outside but I have had some problems with that in the past. I want a thermowell.
I took a standard pepsi ball lock keg and measured the depth from the lid to 3.5 and 3 gallons. They were approximately 7” and 9.5”. I would need a 10-12" thermowell.
I ordered a wonderful weldless thermowell from brewershardware.com for $24. https://www.brewershardware.com/12-Weldless-Thermowell-WLFTW12.html
The problem I discovered was that when you start to tilt the lid to place it inside the keg the end of the thermowell would hit the side and it would not fit.
I decided the only option would be to use a traditional thermowell that attaches to the lid after its on. I like the Duda diesel stainless 30 cm (11.8”
thermowell with 1/2" NPT. It will accommodate the probe from a Johnson temperature controller as well as the short and long probes made by Inkbird. It costs $10.50 plus shipping from Amazon.
Using the appropriate 3/4" to 1/2" NPT bushing, 3/4" NPT locknut, washer, and O-ring you can modify a lid to attach the themowell without welding. All stainless fittings available from McMaster-Carr or Amazon. Total cost for these parts was under $10.00.
I pressure tested the keg to 40 PSI with no leaks. Depth into the keg was 10.5” so is appropriate for 3 gallon batches. Using a 1/2” NPT plug you can go back to using the keg as normal.
I thought I was done with my plans when I had another idea to simplify the method of attaching and removing the thermowell. With IPAs and specialty brews I was concerned with the ease of removing the lid for dry hopping or other additions.
In this version you use a set of stainless quick disconnects, washer, O-ring and 1/2" NPT locknut. The thermowell attaches and comes off in a snap. The only downside besides cost of fittings is that the themowell depth is reduced to 9.5” so you must have 3.5 gallons in the fermenter to make it work.
Quick disconnects were $18.00 on Amazon. The other fittings would cost in the neighborhood off $7.00 but as they were for 1/2” NPT I had them already.
In an effort to lose some weight I have cut down my brewing to 3-gallon specialty batches. So now I have lots of five gallon kegs that aren't getting much use. I decided I would like to turn some of them into 3 to 3.5-gallon batch fermenters. With a shortened dip tube, I can take samples and transfer with no oxygen exposure. Using the gas post I can add a blow off tube or a spunding valve to experiment with fermentation under pressure. For temperature control I wanted to add a thermowell to the lid. I know with a stainless vessel many people just tape the probe to the outside but I have had some problems with that in the past. I want a thermowell.
I took a standard pepsi ball lock keg and measured the depth from the lid to 3.5 and 3 gallons. They were approximately 7” and 9.5”. I would need a 10-12" thermowell.
I ordered a wonderful weldless thermowell from brewershardware.com for $24. https://www.brewershardware.com/12-Weldless-Thermowell-WLFTW12.html
The problem I discovered was that when you start to tilt the lid to place it inside the keg the end of the thermowell would hit the side and it would not fit.
I decided the only option would be to use a traditional thermowell that attaches to the lid after its on. I like the Duda diesel stainless 30 cm (11.8”
thermowell with 1/2" NPT. It will accommodate the probe from a Johnson temperature controller as well as the short and long probes made by Inkbird. It costs $10.50 plus shipping from Amazon.Using the appropriate 3/4" to 1/2" NPT bushing, 3/4" NPT locknut, washer, and O-ring you can modify a lid to attach the themowell without welding. All stainless fittings available from McMaster-Carr or Amazon. Total cost for these parts was under $10.00.
I pressure tested the keg to 40 PSI with no leaks. Depth into the keg was 10.5” so is appropriate for 3 gallon batches. Using a 1/2” NPT plug you can go back to using the keg as normal.
I thought I was done with my plans when I had another idea to simplify the method of attaching and removing the thermowell. With IPAs and specialty brews I was concerned with the ease of removing the lid for dry hopping or other additions.
In this version you use a set of stainless quick disconnects, washer, O-ring and 1/2" NPT locknut. The thermowell attaches and comes off in a snap. The only downside besides cost of fittings is that the themowell depth is reduced to 9.5” so you must have 3.5 gallons in the fermenter to make it work.
Quick disconnects were $18.00 on Amazon. The other fittings would cost in the neighborhood off $7.00 but as they were for 1/2” NPT I had them already.
