Author Topic: Need a Cheap DIY Fermentation Chamber  (Read 1590 times)

Offline Bomber 22

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Need a Cheap DIY Fermentation Chamber
« on: August 15, 2016, 10:57:50 PM »
Thanks to the help here, I've brewed my first beer (well, HME and DME) and first cider.  In order to keep a fairly proper fermentation temperature, I've stored the fermenter in the freezer portion of a non-working refrigerator.  I've been having to do the ice-bottle swap on a daily basis.  I'd prefer not brew again until I can have a fairly functioning fermentation chamber.  And trust me, it's killing me all of the weeks that has gone by since my 2nd batch.  I feel like I'm wasting valuable brew time and the opportunity to stock up and hoard bottles of beer!

I was given a very small 1.X cubic foot mini-fridge.  It's working based on a 15 minute test.  The unfortunate part is that some of the copper lines as well as a terminal contact are rusted.  I was going to initially build a wider chamber around the fridge with styrofoam or ply (as I've seen online).  However, if this fridge is going to conk out based on the rusted lines then I really don't want to put in the money for materials that would be wasted.  I need this to be as cheap as possible, unfortunately.

I brew with a 2 gallon Mr. Beer keg.  I've also got a DIY 2 gallon food grade bucket with spigot that I can add an airlock to. 

I've taken off the inside portion of the mini-fridge door (where you store milk and such).  Unfortunately the Mr. Beer keg does NOT fit inside fridge as it is about 1/2" too wide.  My only option would be to take the spigot off and plug the hole (any thoughts on that?).  However, the bucket DOES fit inside it. 

Questions...

1. This fridge has a little freezer area in the top-right hand portion of the fridge with a little plastic flap door.  This (basically the freezer coil area) will sit a few inches above part of the bucket.  Will this temp variance (fridge vs freezer area) screw with an added temp controller?  On the freezer note, I've read that the freezer will essentially be dripping water all of the time (condensation) because of the lower temperature.  Curious if anyone has had experience with correcting that.

2.  I've read that the STC-1000 is the cheapest way to obtain/create a temperature controller.  I see it's about $16 on Amazon (though I've read it can be found for $10 on ebay).  It sounds like I would have to find or buy something to house the unit.  Also, I don't think it actually comes with wires to do the wiring.  So, I guess the price goes up a bit.  Do I "need" to solder the wires or can I simply twist and cap them?  I've never soldered before and this would be an additional expense to purchase a solder gun/kit.  Granted, if I have to then I will.

Thanks for any advice, hints, tricks and/or info.


Offline Stevie

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Re: Need a Cheap DIY Fermentation Chamber
« Reply #1 on: August 15, 2016, 11:10:13 PM »
Those types of fridges do not have coils in the walls and freezer is what makes the fridge cold. The external thermostat will turn the unit on causing coolant to run through the freezer compartment. When the set point is hit, it will shut off. Do not worry about variances. Adding a fan would help if you have a spare lying around.

Having concern over dripping is smart. Can you put a small sheet pan on the upper most shelf?

If you are at all iffy on electrical wiring, opt for a pre wired model. The latest inkbird dual stage gets good reviews. This unit is so cheap that it's worth saving the effort and cost of building an STC1000 based controller.

Offline Bomber 22

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Re: Need a Cheap DIY Fermentation Chamber
« Reply #2 on: August 17, 2016, 06:27:26 AM »
Thank you.  Good to know about the freezer being the sole cooling source for the entire fridge.  I can definitely rig some sort of tray under the freezer even if it's as amatuerish as putting in a couple of swiffer pads to soak things up or somehow funneling the drips into a cup.

Thanks on the Inkbird tip.  I did some searching on them.  You must be talking about the ITC-308 model.  I see some brewers suggesting them.  I finally figured out that the difference between the 308 and 308S model is that the probe on the 308S is removeable. ...and they sell the 308S with either a 2"-ish and/or 12" probe. 

I've seen some people tape the probe to the fermenter.  Some will dip the 2" probe into a cup of liquid near the fermenter.  Then others get the 12" so that they can hang that directly into the fermenter.

I had not planned on paying that much but I think I might shell out for the 308s with 12" probe.  Thanks.



 



Those types of fridges do not have coils in the walls and freezer is what makes the fridge cold. The external thermostat will turn the unit on causing coolant to run through the freezer compartment. When the set point is hit, it will shut off. Do not worry about variances. Adding a fan would help if you have a spare lying around.

Having concern over dripping is smart. Can you put a small sheet pan on the upper most shelf?

If you are at all iffy on electrical wiring, opt for a pre wired model. The latest inkbird dual stage gets good reviews. This unit is so cheap that it's worth saving the effort and cost of building an STC1000 based controller.

Offline Stevie

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Re: Need a Cheap DIY Fermentation Chamber
« Reply #3 on: August 17, 2016, 01:33:57 PM »
Just get the normal and attach it to the side. In the wort is nice, but there is a lag that the inkbird isn't smart enough to compensate for.

Offline Hand of Dom

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Re: Need a Cheap DIY Fermentation Chamber
« Reply #4 on: August 17, 2016, 02:55:52 PM »
I have the standard Inkbird 308, and just attach the probe to the side of my bucket with plumbers clay.  It's a great little piece of kit (especially those of us who don't fancy burning down the house with our poor quality electrical work).
Dom

Currently drinking - Amarillo saison
Currently fermenting - Pale ale 1 - 2017

Offline blair.streit

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Re: Need a Cheap DIY Fermentation Chamber
« Reply #5 on: August 17, 2016, 03:49:22 PM »
I've seen some people tape the probe to the fermenter.
This works great and doesn't require any additional sanitizing since it's not in the beer. People have done experiments and measured the difference between the center of the wort and the outside of a glass or stainless fermentor at less than 0.5F.

I use painters tape to secure it and an old sponge tied on top with a string (to insulate the probe from the ambient temp swings in the fridge).

Some will dip the 2" probe into a cup of liquid near the fermenter.
This doesn't really tell you anything useful. It does buffer the ambient temp swings inside the fridge, but you care about the beer temp (which would be significantly warmer than the cup of liquid when the yeast are at peak activity).

Then others get the 12" so that they can hang that directly into the fermenter.
Works great, but in my experience it's just an extra hassle to deal with sanitizing a thermowell and making sure all your stoppers and/or fermentors have an extra opening for it.

Offline Bomber 22

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Re: Need a Cheap DIY Fermentation Chamber
« Reply #6 on: August 31, 2016, 10:24:30 PM »
Thanks all.  I ordered the 308s with 2" probe.

Just a heads up.  I was searching to see if there were any coupons or discounts on the brand.  I saw a post come up in the search from another beer brewing forum.  Looked like every now and then Inkbird themselves would post a thread offering a coupon code to a specific model and do other promotions.  In one of the threads, I asked if they would by chance offer a coupon for the specific model that I wanted.  Generously, they obliged.  If anyone is going to grab one of their units, you may want to give that a try as well to save a few bucks.     

I'm going to test out the product in the mini fridge along with a bucket full of water.  Blair.streit, when you say you put a sponge over the sensor....did you completely encompass the sensor or is the sensor seated directly against the fermenter and the sponge is coating the outer portion of the sensor that is not touching the fermenter? Thanks.