Controlling ferment temperatures.

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corene1
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Controlling ferment temperatures.

Post by corene1 »

So here is a question. I have read all the ways to keep a ferment at the proper temperature when it is in a cold environment, but now that it is summer how does everyone go about reducing temperatures. Our day time highs here are between 95 and 110 in the day time and mid 70's at night and my shed is outside and is quite warm. I do most of my fermenting from fall to spring but it is very hard to keep the temps below 80 during the summer months.
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Re: Controlling ferment temperatures.

Post by LBHD »

How big are your ferments?

A lot of homebrewers use chest freezers with temp controllers to keep ferments in the 60-70s throughout the summer. The larger the mass of fluid though, the harder the temp is to control.. a 5 gallon fermenter you can keep stable fairly easily, but a 20 gallon ferment will generate a lot of heat and take a lot to keep cool..

For trashcan-sized ferments, maybe an upright freezer would do? And starting the ferment at a lower temp can help mitigate the change in temperature generated by yeasties-
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Re: Controlling ferment temperatures.

Post by bearriver »

How many ferments are you running at a given time, and how large? If it is one large ferment then I think this will work well for you.

Hydroponics distributors sell reservoir chillers, and they work great. Just set the desired temp and hook it up. Think SS herms coil in the ferment, hooked up to an electric mechanism which pumps cooled liquid through the coil. I found a diy option that is cheap, but its from a site that would probably be inappropriate to link you to. If you Google search "reservoir chiller DIY", you should get the same results I did.

Here is a link with several product options ready to work out of the box: http://www.atlantishydroponics.com/wate ... nd-heaters" onclick="window.open(this.href);return false;" rel="nofollow
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corene1
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Re: Controlling ferment temperatures.

Post by corene1 »

My ferments are in a 15 gallon fermenter and I typically use 10 gallons water and 20 pounds of grain and I do 1 or 2 at a time. The swamp cooler is a good idea, Maybe build a little insulated box and put a small window type swamp cooler in it. Those little window AC units might work too add in a thermostat . I will have to check out the hydroponics shop too. I have a friend that has a shop and we do some trading. His mom does tinctures and uses some of my alcohol for her recipes, and I get fertilizers from him for my pepper plants.
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bearriver
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Re: Controlling ferment temperatures.

Post by bearriver »

If you have the extra time, maybe consider a 15 gallon container inside an old refrigerator? I've seen a few good ole boys round here doing that. The idea is to use a cheap digital thermostat hooked up to an old AC unit & heater. Cool in the summer, and warm in the winter. Plus it is insulated, so it's cheaper to operate.

I would build one, but my 55 gallon screw top wont fit in a fridge from the side of a road. A well house works for now because it is powered, small, and insulated.
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Re: Controlling ferment temperatures.

Post by Sedaterman »

http://homedistiller.org/forum/viewtopi ... 0#p7214810

The original poster in the above link had mistakenly headed his subject matter as "mash temp". He was referring to fermentation temp. That is why I posted in that thread. Clearly this would be the appropriate place.
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Re: Controlling ferment temperatures.

Post by cob »

arizona mister brings air temp down about 30 degrees.
i cool a large area of a 3500 sq ft uninsulated steel shop in the desert with a 5' spud fan. excelsior pillows and drip irrigation parts.
hanging burlab in the door and wetting it with drip or mister parts and blowing a fan out a window works.
old scool woodsmans refrigerator is a burlap box in the shade with a water drip on the burlap.
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Re: Controlling ferment temperatures.

Post by NZChris »

I use old upright fridges that will take a 70l fermenter. They are very convenient, especially if the fermenter has a drain valve.

I worked out how to tweak the controllers to get the temperatures I need because I'm too much of a cheapskate to buy a controller. I have separate controllers for heating and have never needed to have them both turned on at the same time. I already have the next fridge that is to be set up, and have obtained a controller that will enable me to easily dial up whatever temperature I want, summer/winter/dark ales/lager/crash cooling :D

I thought about using a chest freezer, but there is no way I would be able to lift the larger fermenters in and out without a block and tackle.
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Re: Controlling ferment temperatures.

Post by Sedaterman »

You can get the STC 1000 for as low as 15 bucks. Just have to wire. It up yourself.
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Re: Controlling ferment temperatures.

Post by NZChris »

A trick you can do with old fridges, even non-working ones, is to add extra thermal mass to keep the temperature more stable. Bottles & spare fermenters full of water will do. In summer, keep the door open in the evening, close it when the sun comes up. Winter, open the door during the day, close it at night. Spring and autumn around here, the average is about right for most things I do and the extra thermal mass keeps the temperature very even.
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Re: Controlling ferment temperatures.

Post by shadylane »

I have a small sprinkler on top my metal shop.
It will drop the inside temp by 5 to 10 degrees.
Part of the water supply for the sprinkler, passes through a wort chiller in the fermenter.
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Re: Controlling ferment temperatures.

Post by frunobulax »

I use one of these .. http://morebeer.com/products/ranco-digi ... wired.html" onclick="window.open(this.href);return false;" rel="nofollow in a modified freezer.( I didn't get it here) In the summer the fridge part keeps it cool and in the winter I put a small ceramic heater
inside to keep it warm. Ya just tape the probe to the side of the fermenter with a piece of insulation over it to get accurate readings. Or..
Sedaterman wrote:You can get the STC 1000 for as low as 15 bucks. Just have to wire. It up yourself.
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Re: Controlling ferment temperatures.

Post by NZChris »

Today, I pulled a Ranco controller out of a broken down fridge/freezer that is on it's way from my shed to the recyclers. Cost = zero. Got it for nothing and used it as a beer fridge for a few years, then as an incubator and crash cooler for a couple of years until it ran out of gas.

Today, my shed has four incubators, cheese/wine caves, freezers, in various configurations, plus one out in the rain ready for the recycler and a freebee working fridge freezer is arriving tomorrow, also with a Ranco controller for me to repurpose.

If you have the room, an old fridge is much more convenient than running a coil of hose through a fermenter, or pumping water over sacking. Costs more to run though.
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Re: Controlling ferment temperatures.

Post by still_stirrin »

Corene,

I use an old 'beer fridge' the the carboy sets into. It was a garage sale fridge ($10), so it isn't pretty. but works for this purpose. I put a temp controller on it to set the temperature to my lagering temp.

But your 15 gallon fermenter might not fit into a reefer. So if cooling control is needed, you might consider the recirculation jacket idea. Or the fan and blanket evaporative cooler.
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Re: Controlling ferment temperatures.

Post by Sedaterman »

My fermentation chamber is pretty much done. Just need to pretty it up with some paint and stain. Also will dress up the door. Best part is it's completely functional. Four inches thick styrofoam throughout holds the temp very well. The STC1000 works like a charm. Holds two 6 gallon carboys. A fun project.
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Re: Controlling ferment temperatures.

Post by Jimbo »

Corene, chest freezers come in all sizes and are super cheap on Craigslist used. Get the biggest one you can fit and wire up one of them Chinese temp controllers to it. I have 2 now, 1 for keg cooler for beer on tap (fits 6 kegs) and 1 tiny one for a lagering chest, barely fits 2 carboys. Ferments arent a problem for me as my basement stays pretty steady year round, lucky that way.
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Re: Controlling ferment temperatures.

Post by rad14701 »

I've been known to bury a fermenter partially in the ground to take advantage of natural temperatures to help with the excessive heat issue... If too much of the fermenter is in the ground and the wash is getting too cool you can use a submersible heater to even out the temperature swings... A 15 - 20 gallon fermenter buried ~1/3 in the ground with a removable insulated jacket for the above ground portion should work well in most areas... Adjusting the depth buried for your area over successive batches might prove beneficial...

I got this idea years ago after seeing wooden mash barrels buried almost completely in hotter areas to beat the heat...
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Re: Controlling ferment temperatures.

Post by RevSpaminator »

LBHD wrote:How big are your ferments?

A lot of homebrewers use chest freezers with temp controllers to keep ferments in the 60-70s throughout the summer. The larger the mass of fluid though, the harder the temp is to control.. a 5 gallon fermenter you can keep stable fairly easily, but a 20 gallon ferment will generate a lot of heat and take a lot to keep cool..

For trashcan-sized ferments, maybe an upright freezer would do? And starting the ferment at a lower temp can help mitigate the change in temperature generated by yeasties-
For the past couple of weeks I've been digging around for some clues about my hit and miss success with my ferments. The pattern I've noticed, over the past couple of years, has been reliable ferments that always run till they are dry between October and March. Once the warmer weather starts up things become hit and miss. Last year it happened to one batch and I figured I screwed something up with some kind of contamination. This year it has happened to three batches. I have two 20+ gal fermenters and I keep them in a back storage room with no temperature control. In the runs I've watched, the wash started out chugging away like a champ but a couple days later and it is stalled and sg readings have only dropped by ~20%. (I'm starting at around 1.085) I've tried UJSSM and some of my own concoctions, with and without nutrients, all the same, summer ferments are hit and miss.

Funny I didn't think of this sooner. I even went on a distillery tour in April and saw their 500gal fermenters that are water cooled to keep down internal heat buildup. And then I read the above comment and I thought, "Could this really be it?... staring me right in the face?" I've never thought about heat buildup because I don't use turbos. (Never have thanks to this forum BTW.) I don't even take a temp reading once fermentation has started.

Since I have a limited sampling and I know that correlation does not equate to causality, I will be following this up with some further investigation. I'll start by moving my fermenters to an are that isn't subject to the same oven like conditions on warmer days. I will also follow the weather reports and start my ferments during cooler periods. (I get plenty of those in summer where I live.) I'm thinking the crucial part will be the first 3 to 4 days when the yeast are most active.

I'll also try waiting until the wash is cooler before I pitch my yeast. I got in the habit of pitching at around 90F since I typically start the ferment in the afternoon or evening and I want the yeast to get going before things cool down. Again, this is a good strategy in winter because once the yeast are established the wash can safely cool to 55Fand 'lager' for a few weeks. (When I refer to lager I mean a colder slower fermentation.) I'm thinking that letting the wash drop to 75F~80F to give the yeast a little more of a buffer against the heat of their own activity.

I know I'm changing a lot of variables at once, but all are intended to address what I believe to be heat buildup. If I get a positive result then I know I'm onto something and I'll investigate further. If it does turn out to be a heat issue that isn't controlled by tailoring the process to my environment, then I'll have to look into environmental controls.

One last thing.. A big thanks to everyone here for all your time and sharing. The collected knowledge available on this forum far exceeds anything I could have ever found in any book.
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Re: Controlling ferment temperatures.

Post by Lester »

I "dress up" my 15-gallon fermenter in an old T-shirt and keep the T-shirt wet to cool my fermenter.

My fermenter's lid has an indentation and I pour water in that indentation. The fabric will wick and the water will eventually wet the entire T-shirt. This is only good for about 3~4 hours.

To keep the T-shirt wet for more than 12 hours I made a water dispenser from a plastic gallon container. Drilled 2 holes (6mm) on the lid itself, filled the container with water, then placed this inverted onto the fermenter's lid. The water in the container will drain as needed to keep the T-shirt wet.

Yes the water is messy on the floor.
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Re: Controlling ferment temperatures.

Post by S-Cackalacky »

Corene, I have about the opposite problem. I was having big problems in the Winter. I do my fermenting in the basement and it stays at least 10 to 15 dF cooler than the rest of the house in Winter. I had to build a ferment box which consisted of a corrugated cardboard appliance box and a 60W light bulb. I went from not being able to ferment at all to having SF ferments finish in less than 36 hours. For summer the basement is still a little cool, but the box works well without turning on the light bulb.

Lester's method of cooling sounds simple and effective. Maybe you could boost the cooling power a little by having a box fan blowing on it. I guess the trick is keeping it wet.

Edit: Had a thought, and yes it hurt - set your fermenter down inside a larger container (drum) and fill the larger container with water. A water bath of sorts. Or even rig up a cooling water input and output and run it like a liebig with water circulating through it.
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