Space Heater + Closet = Fermentation

[OldGreg]

I'm brewing a Belgian Witbier with WhiteLabs WLP410 Belgian Wit II Ale Yeast. I've read that higher fermentation temps will result in better flavors with this yeast so i'm shooting for the high end of the suggested temps. My room temp is around 60-64 this time of year and the recipe calls for 68-72.

Option 1: Could I use a space heater in a small closet (see picture) to bring the temperature up? Or is this a bad idea?

Option 2: I do not own a temperature controller but I do have everything else to make a lightbulb/paint can heater. Would leaving this type of heater on continuously be too hot?

 

[mongoose33]

I would not, in any universe, put a space heater in an enclosed closet. That's asking for trouble.

You're much better off trying to control the temp of the fermenter than the space around it. Since heating is your issue, you're probably far better off using a reptile heat mat like

https://www.amazon.com/dp/B01LZXOP1C/?tag=skimlinks_replacement-20

instead of indirect heat. Use bungee cords or similar to wrap the reptile heater around the fermenter. If it's too hot, try getting some of it out of contact w/ the fermenter, or insulate part of that w/ a piece of styrofoam or similar under part of the reptile mat.

I have that very mat, works fine. If the ambient is a little too cool for it to keep up w/ the fermenter, I put a towel over it to direct more heat into the fermenter and less into the ambient environment.

 

[SoCal-Doug]

I am not feeling any love for this method whatsoever. Your home being fully engulfed in flames will not make good beer.

Bring it inside, let it share your home (whatever the warm room is). Wrap it in a nice cozy blanket.

 

[OldGreg]

I will definitely not use the space heater! Those temps are inside my apartment. The warmest place keeps a cup of water at 64. I will probably buy a heat mat.

 

[ESBrewer]

Another simple setup that works with some fermentation vessels is waterbath + aquarium heater with thermostat (~25$). I don't heat up the fermentation but those devices are simple, reliable and precise enough. It's a good idea to have a small pump or aq.filter to circulate the water to avoid temperature gradients. When the fermentation begins and heat is going to build up inside the fermentor, water is much more efficient in cooling down the bucket than the air in the room/closet.

 

[mongoose33]

Here's a pic showing how I put my reptile mat around the fermenter. The fermenter on the left has the reptile mat; on the right I'm using a FermWrap. FermWraps are about twice the price of the reptile mat.


I just place it inside the lifting straps; the bungee cord helps hold it against the fermenter, and allows me to also use a piece of closed-cell foam to hold the inkbird temp probe against the fermenter so it's measuring the temp of the fermenting wort, not ambient.

[I have two batches going at one time, which if you have two Inkbirds and two heating mats, can be done--see this thread if you want to know more about that: https://www.homebrewtalk.com/forum/...tions-one-ferm-chamber-it-can-be-done.631776/ ]

I control them using an Inkbird. If you can be patient, the Inkbird merchant here runs specials on them from time to time, often for 20 percent off at Amazon. That drops the price to about $28-30. It's the best way to control temps and, if and when you get a refrigerator ferm chamber, it'll control both the refrigerator and the heat mat.

 

[OldGreg]

Thanks, great info!
I bought the heating mat you suggested. I would like to avoid buying a controller as of right now. Any thoughts on running the heating mat 24/7? I’m thinking about putting some closed cell foam or reflectix between the fermentor and heating pad to keep from overheating. Any thoughts on this approach?

 

[mongoose33]

Thanks, great info!
I bought the heating mat you suggested. I would like to avoid buying a controller as of right now. Any thoughts on running the heating mat 24/7? I’m thinking about putting some closed cell foam or reflectix between the fermentor and heating pad to keep from overheating. Any thoughts on this approach?

You're going to have to monitor the temp and see what you get. The problem is that yeast is exothermic, meaning it will add 5-10 degrees of heat to the wort during active fermentation.

That means you probably won't need much additional heat after the yeast gets going, but somewhat more before they do get going, and more after they slow down a bit.

Some of this also depends on how cold every place is in your home.

What I'd probably do is put about half of the heat mat in contact w/ the fermenter, and have either a stick-on fermometer from which you can determine temp, or some other means of checking temp of the fermenting beer.

If that doesn't raise it enough, put some more of the mat in contact w/ the fermenter. The mat is only 21 watts, which is not a tremendous amount of heat. My guess is half in contact w/ the fermenter at first will work fairly well, but this is all empirical, meaning you simply have to try and see what happens.

If you have a spare fermenter you could fill it with water and see what it takes to get it to hold a specific temperature with the mat.