Even more help with ferm chamber

Hi All,

So I have made my chamber....I have my little square magic chef, no idea the cubic feet. gotta be like 1.?? at any rate, this lil fridge must be a cooling beast..or my house is so cold that well,i just dont know. The last batch i brewed was supposed to be between 65-68, so that worked ok i suppose....after I realized it was supposed to be there. I have a batch of "off" beer now because of the huge temp swings. Well the batch I brewed this past weekend has a ferm temp of 67-74. Well, with the fridge at near 0 (which on mine is almost OFF), the carboy sitting inside, the doors wiiiiide open, my thermo says its 66. This would be a wired thermo with a probe that i tape to the side of the carboy. Well, this concerns me as i have another vessel in the chamber that has a long probed thermo in water, this one reads 64. If I am thinking correctly, this means the liquid temp is 64 really? or my thermos are just off from each other. I digress....i am worried that i am not going to be able to keep my wort warm enough! which is the opposite problem i had before...grrr. During the day, the ambient temp in my house is roughly 74 and at night its roughly 68. Can someone give me some pointers?? I have a ranco on the way to control the fridge, but at this rate, it may never turn the fridge on!

TIA,

M

Everyone must be grilling and drinking their HB!

we had a guy in our homebrew club do an experiment with some thermowells, stick-on thermometers, thermometers next to the fermenter, and thermometers in a jug of water next to the fermenter. even though they were all calibrated and extremely close to each other, there was a distinct difference between them all. his recommendation was to use a thermowell for best possible accuracy.

I doubt that when you get the ranco wired up the fridge will turn on much at all...especially once the fermenter reaches your desired setpoint. In the winter time, the guys I know use a heating source because the fridge is just too darn cold...you may need to do the same? one of those belt warmers or a light bulb.

not sure if the ranco can be used in that manner (controlling hot & cold), but until you get a controller on there, be very careful to monitor temperature. I just modified a cabinet to use as my chiller, and I ended up cooling the fermenter so low that the yeast got stressed and starting throwing sulphur. luckily, I listened to the voices of experience in the club and DIDN'T toss it out when I noticed the sulphur. patience is not my best quality, but I waited anyway...I just racked to secondary yesterday and didn't notice any sulphur taste at all.

If the problem is that the chamber is too cold, hook the controller up to a heating pad or some other heat producing device.

For the record I'm eating Chinese...

B.

jtucker101 said:

we had a guy in our homebrew club do an experiment with some thermowells, stick-on thermometers, thermometers next to the fermenter, and thermometers in a jug of water next to the fermenter. even though they were all calibrated and extremely close to each other, there was a distinct difference between them all. his recommendation was to use a thermowell for best possible accuracy.

I doubt that when you get the ranco wired up the fridge will turn on much at all...especially once the fermenter reaches your desired setpoint. In the winter time, the guys I know use a heating source because the fridge is just too darn cold...you may need to do the same? one of those belt warmers or a light bulb.

not sure if the ranco can be used in that manner (controlling hot & cold), but until you get a controller on there, be very careful to monitor temperature. I just modified a cabinet to use as my chiller, and I ended up cooling the fermenter so low that the yeast got stressed and starting throwing sulphur. luckily, I listened to the voices of experience in the club and DIDN'T toss it out when I noticed the sulphur. patience is not my best quality, but I waited anyway...I just racked to secondary yesterday and didn't notice any sulphur taste at all.

Click to expand...

Thanks for your reply. Forgive my ignorance but when you say his recommendation was to use a "thermowell" what exactly do you mean?

I live in the south, but I am sure in the winter I may need some source of heat. The ranco is only a single stage unfortunately. My house actually got so cold for my first batch it did the same thing you are describing with the yeast. I did have the effect of some off flavors...so i am glad i started the chamber.

TIA,

M

I've read on here somewhere that you can switch one of the leads inside the Ranco and it will go from cooling to heating. I'll rot round here and see if I can find it again, but the interwebs are running really slow for me on the boat today.

There is also this option...
Ranco ETC-211000-000: 2 Stage Prewired Temperature Controller

That would allow you to control both heating and cooling with the same unit.

B.

gambleb said:

If the problem is that the chamber is too cold, hook the controller up to a heating pad or some other heat producing device.

For the record I'm eating Chinese...

B.

Click to expand...

I havent yet gotten the controller in the mail....but I believe you may be correct. It's so hot outside....i keep the temp pretty low in the house but I never imagined I would have to warm my beer!

Never mind... That post was talking about the analog Johnson controls one. Sorry.

gambleb said:

Never mind... That post was talking about the analog Johnson controls one. Sorry.

Click to expand...

Thanks for looking!

rhltechie said:

Thanks for your reply. Forgive my ignorance but when you say his recommendation was to use a "thermowell" what exactly do you mean?

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a thermowell is typically a metal tube that has a removable temperature probe inside. it gets inserted down into the fermenting vessel so the metal tube is in direct contact with your fermenting wort. the tube is typically filled with liquid (star san or sanitizing fluid) to help act as a thermal conductor.

quite a few people use corny keg dip tubes, with one end welded closed...and a digital thermometer probe inserted. do a search on morebeer.com or midwest supplies and you'll probably get a better idea than my mediocre description.

oh, and we're not grilling out...eating chick-fil-a we got for free ("wear your team logo for a free sammich" day)

jtucker101 said:

a thermowell is typically a metal tube that has a removable temperature probe inside. it gets inserted down into the fermenting vessel so the metal tube is in direct contact with your fermenting wort. the tube is typically filled with liquid (star san or sanitizing fluid) to help act as a thermal conductor.

quite a few people use corny keg dip tubes, with one end welded closed...and a digital thermometer probe inserted. do a search on morebeer.com or midwest supplies and you'll probably get a better idea than my mediocre description.

oh, and we're not grilling out...eating chick-fil-a we got for free ("wear your team logo for a free sammich" day)

Click to expand...

ahhh..i gotcha. i saw them on the ranco site a while back, just didnt understand at the moment. thanks!

and i forgot about logo day!! grrrrrr

A probe thermometer taped to your vessel will not take an accurate reading. You may already be aware, but there is a dimple in the probe where it takes the temperature. This would need to be submersed for accuracy. Other wise you are taking some poor middle ground between the temperature of the ferm vessel and the ambient temp.

northernlad said:

A probe thermometer taped to your vessel will not take an accurate reading. You may already be aware, but there is a dimple in the probe where it takes the temperature. This would need to be submersed for accuracy. Other wise you are taking some poor middle ground between the temperature of the ferm vessel and the ambient temp.

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Yes, I realize this isn't the most efficient method. It's all I have at this point so I am trying to do the best with what I have. When funds allow I am looking into the thermowell for the ranco I purchased.

gambleb said:

I've read on here somewhere that you can switch one of the leads inside the Ranco and it will go from cooling to heating. /snip
B.

Click to expand...

You can change the single stage ranco from heating to cooling right in the menu. press "set" 4 times, then change "c1" to "h1", swap the fridge plug for your heating device.

When you have a theromwell ready for your fermenter first add enough transistor thermo potting paste inside the tube before installing your temp probe. Make sure you have enough added so that the probe is completly submerged after it has been installed and pressed down until it stops against the bottom of the thermowell. This will allow for quick heat transfer of the fermenter's core temp. Add a little slack to the probe leads then silicone seal at the top preventing any strain on those small gauge probe wires. better yet is to solder a compression fitting to the end of the thermowell tubing and tighten down the rubber cone with the nut like a small CGB fitting. This making it waterproof as well a strain relief. Just some ideas to think about.

brewbeemer has a good point...the thermowell filled with sanitizer would work well for one of those metal temperature probes...although you may have to waterproof the wired connection on it so liquid doesn't get down inside the probe.

from looking at the temperature probe on a ranco, I don't know how water-tight it would be, and it doesn't look like it is metal. submerging it into liquid might not be a very good idea, so some thermal paste would probably be better suited for it?

then again, you might be able to altogether skip any form of conductive medium (depending on how tight a fit there is between the probe and thermowell). you shouldn't get rapid temperature fluctuations from the probe once it's installed and the controller is probably using some form of hysteresis. with a fairly large volume of liquid to try to heat/cool, there is no way you're going to need microsecond-based temperature accuracy...especially when the fermenter isn't ever a uniform temperature to begin with.

someone may want to weigh in on whether or not those ranco probes are submersible...I'm not exactly sure?

jtucker101 said:

then again, you might be able to altogether skip any form of conductive medium (depending on how tight a fit there is between the probe and thermowell).

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I ended up getting a two stage ranco. The probe i do not believe is supposed to be submerged so I got a thermowell. the fit between the probe and the thermowell is like a glove so i havent put anything in it.

funny thing....the temp on the controller, EXACTLY what the thermo taped to the carboy said. I suppose it may be different when fermentation just starts, but not so much now. Thanks for all the replies.

I have a Johnson Controls A419. bought it before I knew I could get a two stage for just a little more. Plannin on using the Johnson Controls for the kegerator. I was going to use it for fermenting but will use a two stage ranco instead.

northernlad said:

A probe thermometer taped to your vessel will not take an accurate reading. You may already be aware, but there is a dimple in the probe where it takes the temperature. This would need to be submersed for accuracy. Other wise you are taking some poor middle ground between the temperature of the ferm vessel and the ambient temp.

Click to expand...

Don't forget that the fermentation process gives off heat itself. having the reading from the actual liquid, not the surrounding environment is ideal. So you are right, taping it to the side would not be as accurate. Not sure of how off it would be though. Could be a little difference, or a whole bunch. Just make sure you use a thermowell. They make thermowells for a reason, you can't put a probe straight into liquid.