detz

Recipes 

I'm building a dual-fermentor box so I can control the temp for two beers at once and I have the cooling part down I just need some advice on the warming part. I thought about the fish tank heater but I would rather not have water in this thing so I've been looking at heating mats and bulbs. The mats just seem safer to me but I'm not sure they'll be able to heat it up enough. If I have a pretty well insulated box hopefully any amount of heat will be enough. I basically need to heat it from about 50 to 70 degrees. Which is better?

http://www.amazon.com/Zoo-Med-ReptiTherm%C2%AE-Under-Heater/dp/B0002AQCKA/ref=pd_sim_k_6

http://www.amazon.com/Zoo-Med-ReptiCare-Ceramic-Infrared/dp/B0002AQCPK/ref=pd_sim_k_4

MalFet

Recipes 

What about a fermwrap? I'm not sure I'd want my heat source sitting on the bottom. (Rightly or wrongly) I'd feel like I was cooking my trub.

detz

Recipes 

I would stick the bad on the wall not under it. I'm trying to make this cheap, the fermwrap seems pricey for two.

MalFet

Recipes 

http://mattmegbrew.blogspot.com/2009/11/cheap-fermwrap.html

Edit: I'm sure on the side would be fine. Just seems like fermwraps distribute the heat a little more evenly due to the larger surface area.

detz

Recipes 

Awesome, thanks.

I'm guessing these things pull very little in power so a relay like http://www.sparkfun.com/products/100 should work just fine, no?

MalFet

Recipes 

I suspect so, though obviously check before you start melting things. 5A at 250VAC should be enough power to run one of these suckers, considering they're not meant to get any more than slightly warm. The fermwrap itself only draws 40W.

rudu81

Recipes 

I'd buy one of the small portable space heaters for $10 at Walmart (or somewhere similar). But it also depends on the controller that you are using.

BirdBear

Recipes 

I have had very good results with my Brewers Edge (http://www.williamsbrewing.com/BREWER_S_EDGE_SPACE_HEATER_P518C100.cfm) space heater in my fermentation chamber. If you're looking to reduce cost, the ReptiTherm would probably work well for less money, but I've never used one.

The FermWrap scares me a little because I would assume that it heats to a very high temperature in order to change the temp of the whole system quickly. That is, it may always heat to ~90 degrees and then shut off when the ambient temperature of the fermentation chamber reaches the programed temp on the controller. I wouldn't want something heating to ~90 degrees (i don't actually know how hot it could get) against my beer.

I have used ceramic space heaters before, but my temp controller does not register temp changes quickly enough to shut the heater down at the programmed temp. With a ceramic space heater plugged into my Controller II (http://www.williamsbrewing.com/CONTROLLER_II_P183C100.cfm) I have measured temperatures as high as 90 degrees F when my controller only read 60. I think that in a relatively small space, these heaters work too efficiently.

I say go with the heating pad stuck to the side of your chamber. Let us know how the Reptitherm works out if you go that route.

detz

Recipes 

Space heaters scare me, I don't want to leave it unattended for fear it would catch fire or something. The FermWrap is still pretty cheap so I might buy 4 feet and wrap it around the box so it's ambient heat instead of direct.

rudu81

Recipes 

You could also use a reptile heat lamp or similar. http://www.amazon.com/Zoo-Med-Nocturnal-Infrared-Incandescent/dp/B000255OUE/ref=sr_1_2?ie=UTF8&qid=1295478295&sr=8-2