When it comes to fermenting, temperature is one of the most important steps towards happy yeast.
Ale yeast is happiest at 68 to 72°F, while lagers usually perform best at 45 to 55°F.
Previously, we discussed options for controlling your fermentation temperature.
However, controlling temperatures is only piece to the puzzle. Actually heating and cooling your fermenter is another animal altogether, and it usually requires a separate device or two.
This time, we'll share some options to help you condition your fermentation station, whether you need to bring the heat or chill it out.
Some of these devices have their own temp controllers, so in those cases, no external controller is needed. But most of these gadgets don't have a controller built in, so you will need to add one. A very reliable controller is the Johnson A419.
Remember though: Ambient temp doesn’t always equal beer temp. That’s where our previous post is important.
OK, on to the gadgets. We're going to assume here that you're not quite ready to make the leap to a 20 gallon glycol cooled conical. So the options below are more realistic for the wallet.
And while this is not an exhaustive list, we hope that it gets your creative gears moving, and takes you one step closer fantastic homebrew.
Portable air conditioner
- 1 Portable air conditioner
- 2 Window unit air conditioners
- 3 Heating Belts
- 4 Heating lamps
- 5 Converted Refrigerator or Chest Freezer
- 6 BrewJacket
- 7 Ss Brewtech FTSs
- 8 Seedling Mat
- 9 Cool Zone Cooling Jacket
- 10 What do you use to heat or cool your fermenters?
- 11 Get My #1 Technique for Fixing Off-Flavors in Your Beer
- Portable/Movable – If you need to be able to pack up in between fermentation sessions, these are generally on rollers so they can easily be stored when needed.
- 120v – You won’t need a special outlet. You can find NEMA 5 plugs generally all over the house, at least in the United States.
- Generally rated for larger rooms than fermentation, so there is plenty of cooling power.
- Somewhat Loud (50+dBa) – 50dBa is still quieter than a car on a highway, but introducing noise to the home can be a bother.
- Most units need to vent. Air conditioners produce condensation and hot air. It needs to go somewhere.
- Controlling with external controllers is iffy with digital units. If you use an external controller, they generally turn the power off/on as a means of controlling. Check to make sure your unit will auto-cycle after “power outages”.
Here's the best portable air conditioners on Amazon that I personally recommend. It cools fast and has held up to a lot of my bumping and bruising it moving it around the shop.
Window unit air conditioners
- Conditions rooms fast. These are built for cooling entire living areas. Your fermentation room is most likely significantly less square footage.
- Bigger brother of portables.
- Easy to find. Go in to your favorite DIY or box store. They are in the big boxes on the bottom shelf.
- Power/compatibility with external controllers. While I’m not an electrician, many others have noted that most controllers are rated for 10A output or less. While newer energy efficient models are well under that, double check your compatibility before frying a controller (or a window unit for that matter).
- Loud – Starting in the mid 50dBa’s, window units introduce a droning to your peaceful environment. Be prepared to take that into consideration.
- Venting – Much like the portable units, air conditioners create hot air to make cold air. Don’t fight against yourself.
- Weight – at 40lbs+, be ready to secure this beast.
If you have to go with window rattler air conditioner, go with this one on Amazon. It's priced fair and has a lot of customers that are very happy with it.
- (lack of) Noise – This is a big plus for me. I want to have good beer, but not at the sake of disrupting the peace of my household. Not a problem for heating belts.
- Easy on/off control – These run on simple resistance. The only on/off is tied to your temp controller of choice.
- Small – Again, if space is an issue, belts and wraps store away nicely in a bin, tray or cabinet.
- 1 per fermenter – If you have multiple fermenters, you'll need multiple belts.
- Hot Spots – This may only be in my head, but it’s something you will want to watch. This can be minimized with smart temp-probe placement, but it will take experimentation.
- Durability. As Billy B. told me, “I had a FermWrap and it completely fell apart on me”. Your mileage may vary, but replacement may come earlier than other solutions.
Get your own BrewBelt Heating Belt here. You won't regret getting this one.
- Great for bringing temp up – The heat that comes off of heating lamps can make for quick heating options.
- Entire fermentation chamber – One per chamber, so if you have multiple fermenters, there’s still only one lamp needed.
- DIY Options – These homemade bucket + heating lamp setups have become popular too.
- Fire Risk – This and the next line go hand in hand. It’s a light bulb. They get hot. Make sure you keep away from flammable items.
- Too Hot? – Positioning is everything. You don’t want to encourage bacteria growth with higher temperatures.
- You must block out the light so you don’t skunk the beer. Buyers beware, and plan accordingly. Ideas like the DIY Bucket + Heating lamp can help.
*Update – I now recommend you get a safer version of the old “bulb style” heat lamp. These ceramic heaters do a great job with out the potential risks of fire and last a lot longer that a standard bulb does too. They also screw right into a light socket!
Converted Refrigerator or Chest Freezer
- Self contained – If you already have a spot for a refrigerator or freezer, you are but one temp controller away from a dedicated environment. Cheers!
- No venting – The detriment of conditioned air doesn’t apply here. Refrigerators are built to keep the cool in and the heat out.
- Size – It’s a refrigerator (or a freezer). They’re big. They don’t pack away after use.
- Cost – Unless you are replacing an existing one in working condition, or can pick one up on the used market, refrigerators and freezers are on the more expensive end for this dedicated purpose.
- Only one temperature per unit. This can be a problem with multiple fermenters.
- Self Contained – It sits on top of your fermenter, in your beer.
- With their newer model, the BrewJacket now cools and heats
- It has its own built in temp controller. What else do you need?
- Small footprint – Again, there’s no more floor space needed than you are already taking up with your fermenter. If space is an issue, this is an attractive option.
- 1 per fermenter – I could loosely come up with a plan to extend some of these one-per-fermenter setups. The BrewJacket? I’ve got nothing.
- Cost – List price at the time of writing starts at $199. That can get pricey when multiplying by fermenters.
Ss Brewtech FTSs
- Fermentation Nirvana – If you can’t afford a jacketed glycol professional fermenter (in other words, most of us non-pros), then this can get you close. It’s obvious Ss BrewTech really thought this product out.
- Chills and Warms – Whatever control you need, just adjust the water source for hot or cold conditioning.
- Straight looks awesome, especially when stacked.
- Cost – List price is US$249.95 plus the cost of the fermenter itself.
- Made for specific fermenters – This is designed especially for BrewTech’s fermenters. Perhaps in the future there will be a generic option, but for now you need an Ss BrewTech fermenter.
- Space – Requires a cooler to hold the water for conditioning.
Check out Billy B.'s video review of the FTSs system and the stainless steel bucket fermenter.
- Even distribution heating across pad – You can build a fermentation environment with this integrated into the base. The heat will distribute across the whole area.
- Potential for multiple fermenters – These come in multiple sizes. Get the one that best fits your brewing area.
- Hot enough? In theory this would be the equivalent of electric radiant floor heat. That means I already know the answer is yes, it will heat up to whatever temp you need it to. However, is the output the same as radiant floor heat? I plan to answer that question soon.
- Heat only – In the summer will you need to bring temps down? You will need a separate cooling device for that. Plenty of options in this article.
Cool Zone Cooling Jacket
- Flexible – it fits many sizes of carboys, buckets, and conicals.
- Works with both water and glycol.
- Easily scalable for different batch sizes
- More complicated to set compared to other options here.
- You'll need to add units as you add fermenters, so the cost can grow on you.
What do you use to heat or cool your fermenters?
As you can see there are many options to condition your fermentation area, each with their good points as well as bad.
Homebrewers are a clever bunch and are always coming up with new gadgets to serve them. Do you have any to add? Add them in the comments below!