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General Category => Equipment and Software => Topic started by: liquidbrewing on October 22, 2010, 11:57:46 AM

Title: Heating a Fermentation Fridge
Post by: liquidbrewing on October 22, 2010, 11:57:46 AM
I currently am fermenting in a fridge with a Johnson controls analog external thermostat.  With the upcoming "winter" here in Florida approaching, I wondered what the best option for heating my fridge would be.

My fridge is in my garage, and despite popular belief, it can dip as low as into the 30's here at night.

Any ideas?  I've been considering buying a two stage controller, but I still need a heat source.  What kind of heat source will work well for the entire fridge?  Anyone had any successes they'd like to share? 

Thanks!!
Title: Re: Heating a Fermentation Fridge
Post by: wingnut on October 22, 2010, 12:09:43 PM
Before I moved my fermentations to the basement, I used a "BrewBelt" on my plastic buckets.  I do not know how well that would work on glass.

Some people I know take an incandecent light bulb, and just cycle that on and off to produce heat.  If you are using glass, however, I would recommend some paper or cardboard around the carboy.   I do not recall if incandecent light will turn beer skunky or not, but my suspicion is that it will. 

I have also heard people have good luck with an electric heating pad... not up against the carboy, but in the fridge.  They also make a "Fermwrap" I think is the name... that works like the brewbelt, but the heat is more evenly distributed.

Good luck!
Title: Re: Heating a Fermentation Fridge
Post by: bluesman on October 22, 2010, 12:12:13 PM
There are heating devices that will enable you to control the temp of your beer.

http://www.northernbrewer.com/brewing/brewing-equipment/fermenting-equipment/fermentation-temperature-control

If you are planning to heat your beer why do you want to heat it in the fridge?
Heating can be done in the garage.  You will need to attach the controller thermocouple somewhere on the outside of the fermentation vessel so that it will not be affected by the heating element but will accurately monitor the beer temp. You should insulate the thermocouple and the beer during this process.
Title: Re: Heating a Fermentation Fridge
Post by: Steve on October 22, 2010, 02:25:35 PM
Some people I know take an incandecent light bulb, and just cycle that on and off to produce heat.  If you are using glass, however, I would recommend some paper or cardboard around the carboy.   I do not recall if incandecent light will turn beer skunky or not, but my suspicion is that it will.

Remember that brew belts are not recommended for glass carboys.

I've read contra information about what light sources skunks beer.  Some sources report that the UV in sunlight and florescent light energy cause skunking.  Other sources tell us that all forms of light energy will skunk beer.   a10t2 replies below that "green" light is the skunkifier.  All of the sources i read mention prolonged exposure to light.  Would you say that the light energy emitted from the bulb heating the fridge interior is prolonged or occasional?  

How about a couple of red party light bulbs (not the ones used on buffet lines to keep the food hot). The "color" of light energy is on the opposite end of the spectrum from UV and it still produces lots of heat energy.

  
Title: Re: Heating a Fermentation Fridge
Post by: a10t2 on October 22, 2010, 02:47:47 PM
The optimum for skunking is actually about 400 nm (green light). An incandescent bulb will produce light at those wavelengths, but not nearly as much as a fluorescent. If it's exposed for long enough, though, you will get skunking.

http://www.homebrewersassociation.org/forum/index.php?topic=409.0
Title: Re: Heating a Fermentation Fridge
Post by: wingnut on October 22, 2010, 03:08:27 PM
All of the light/skunk information looks like what I have read.  Just to be safe, wrap the carboy in a t-shirt, cardboard, paper...etc..  it is a minimal amount of effort for a lot of piece of mind. 
Title: Re: Heating a Fermentation Fridge
Post by: piszkiewiczp on October 22, 2010, 03:17:29 PM
If you are really set up to screw in a light bulb as a heat source for your box, you could substitute an Infrared emmiter used for keeping pet snakes and turtles warm. e.g. http://www.thatpetplace.com/pet/group/2533/product.web.

There are also heating pads and "hotrocks" but at that point you're better off with a carboy heater and t-shirts.   
Title: Re: Heating a Fermentation Fridge
Post by: tschmidlin on October 22, 2010, 04:05:33 PM
The first thing I would do is get a digital thermometer that has a memory and will record the high and low temp.  I'd monitor the temps in the fridge and see how much the temp drops overnight, and I'd want to know the high and lows in the garage as well.  The garage will mitigate some of the temperature swing outside, and the fridge will mitigate some of the temp swing that the garage sees.  It's possible that the problem isn't so severe or frequent that you need to do anything really.

If you do though, yeah, a 2-stage controller is the way to go.  A light bulb in a coffee can should do the trick, or a reptile heating pad.
Title: Re: Heating a Fermentation Fridge
Post by: bluesman on October 22, 2010, 04:33:50 PM
The first thing I would do is get a digital thermometer that has a memory and will record the high and low temp.  I'd monitor the temps in the fridge and see how much the temp drops overnight, and I'd want to know the high and lows in the garage as well. 

This is sound advice.  Once you understand the environment you can then come up with a method to compensate for the temp swings.

Let us know how you make out.
Title: Re: Heating a Fermentation Fridge
Post by: Wesbrau on October 22, 2010, 08:26:38 PM
If you are really set up to screw in a light bulb as a heat source for your box, you could substitute an Infrared emmiter used for keeping pet snakes and turtles warm. e.g. http://www.thatpetplace.com/pet/group/2533/product.web.

This is what I do and it works great.  I purchased at a pet store a ceramic terrarium heater "bulb" (I forget the wattage at the moment).  Right next to the ceramic bulb in the store was a socket rated for the wattage of this cerabmic bulb, which had a wire cage around it for safety.  It works great plugged into my dual stage controller -- I set the temp for each stage on my controller to my desired ferm temp and set the differential to 1 degree F.  My ferment temperature is always spot on.
Title: Re: Heating a Fermentation Fridge
Post by: dcbc on October 27, 2010, 03:35:44 PM
I use a low watt incandescent bulb on a two stage temp controller.  I run the heat cycle about two degrees lower than the cooling cycle and have a 1 degree diff. set on top of that.  When I had a single stage controller, I went about 4 months with leaving the light on and letting the chest freezer fight it.  This was inefficient of course and let to a good deal of condensation in the freezer.  I ferment in a SS corny keg so no worries about light although I'm told that incandescent bulbs are not a worry.
Title: Re: Heating a Fermentation Fridge
Post by: IHBHS on October 27, 2010, 10:46:03 PM
A brew belt tacked up inside the fridge will produce enough heat to keep the fridge warm enough.  It doesnt have to be wrapped around the carboy, and I would actually put it at the very bottom of the fridge in that dead space where the drawers usually go.  That will heat it from the bottom up and help better evenly heat the fridge.
Title: Re: Heating a Fermentation Fridge
Post by: jaybeerman on October 27, 2010, 11:08:44 PM
A brew belt tacked up inside the fridge will produce enough heat to keep the fridge warm enough.  It doesnt have to be wrapped around the carboy, and I would actually put it at the very bottom of the fridge in that dead space where the drawers usually go.  That will heat it from the bottom up and help better evenly heat the fridge.

+1.  I do the same thing with the carboy wrap, though, I only use mine after fermentation has subsided. Otherwise the fermentation usually provides the necessary warmth.
Title: Re: Heating a Fermentation Fridge
Post by: roguejim on October 28, 2010, 09:55:19 AM
This sounds a lot like this thread I started awhile back:
 http://www.homebrewersassociation.org/forum/index.php?topic=3522.msg40032#msg40032

I was told to reverse a couple of wires in my Johnson controller, and run a 40-watt light bulb through it for heat.  I haven't had the nerve to open the Johnson yet...
Title: Re: Heating a Fermentation Fridge
Post by: tschmidlin on October 28, 2010, 04:04:50 PM
The difference there is you have a single stage controller.  If you got a two-stage, then hooking one up to a heat source like a brew belt/heating pad/40 watt bulb is a good way to go.  If the OP decides not to get the two-stage controller, then swapping he wires will work.  Alternatively, he could get another single-stage controller and swap the wires so he can both heat and cool.

If your ambient will fluctuate around your setpoint, you really need to heat and cool.  In other words, if ambient will swing between 50 and 60F, but you're trying to keep your fridge at 54F, you probably want the two-stage.  But if ambient in your garage is going to be 40-50F, then you can just swap the wires.  For me, the ambient in the winter is less than 50, so I swap the wires to heat when I'm trying to ferment.  In the spring I switch it back to cool.

Makes sense?   :)
Title: Re: Heating a Fermentation Fridge
Post by: ryantj on October 28, 2010, 04:55:16 PM
In fall like this I use a 25w or 40w bulb covered with tin foil and is always on in my ferm. fridge and then the fridge is on my Johnson. Yes that hurts. Once it gets cold enough and I do not need to cool I switch to a heating pad on my Johnson. Yes that feels good. I'd switch to a two stage controller if I could afford it but there always seems to be other priorities since I have a working Johnson, despite what my wife says.
Title: Re: Heating a Fermentation Fridge
Post by: mabrungard on October 28, 2010, 05:25:27 PM
I have found that just placing a regular electric heating pad in my fermentation chamber will provide enough heat to keep the temperature from dropping too much in the winter.  My chamber has a digital Johnson controller to apply the cooling.  That controller is left at the desired fermentation temp and the heating pad is mostly uncontrolled.  I say mostly uncontrolled because most pads have a 3-position power switch that allows me to dial up the energy input when needed, or reduce it if the cooling system is coming on too often.  Its the way to go and its cheap.  You can find heating pads for around $15.  You do need to find a pad that does not have an automatic shutoff timer in it.  They are available. 

Oh, and you can use your heating pad for your aches and pains too.
 
Title: Re: Heating a Fermentation Fridge
Post by: jeffy on October 28, 2010, 05:35:05 PM
I have found that just placing a regular electric heating pad in my fermentation chamber will provide enough heat to keep the temperature from dropping too much in the winter.  My chamber has a digital Johnson controller to apply the cooling.  That controller is left at the desired fermentation temp and the heating pad is mostly uncontrolled.  I say mostly uncontrolled because most pads have a 3-position power switch that allows me to dial up the energy input when needed, or reduce it if the cooling system is coming on too often.  Its the way to go and its cheap.  You can find heating pads for around $15.  You do need to find a pad that does not have an automatic shutoff timer in it.  They are available. 

Oh, and you can use your heating pad for your aches and pains too.
 
In case your fridge is on your Johnson?