Influence of Atmospheric Conditions (??)

[emow54]

After a couple of years and a generous pear harvest in the front yard, I decided to dust off the rig. I had to do some minor repairs and adjustments, but got it up and running today. I did a basic water run to check connections. Then a vinegar run, followed by a sacrificial run to reacquaint myself with the process.

Previously, I had made UJSSM. Everyone that I have shared it with loved it. At that time, I was a beginner and kept relatively decent notes and used the thermometer crutch. Today, the temperature was 20 degrees (191 F) higher at the beginning of production. It used to kick off around 175F. Can/will humidity, temperature, etc. cause that large of a swing in temperature? I fully understand and practice touch and feel over gauges and timing, but curiosity has gotten the best of me.

I used to work in the kitchen on the stovetop. but my wife decided she did not like me doing that. So this time, I worked in the garage.


Edited for additional information:
My sacrificial wash today wash 20-25% ABV mix of diluted cheap grain likker and an old apple jack experiment. My UJSSM washes would finish ferment around 12-14%. In theory, today should have started sooner at a lower temperature. The only modification I made to my pot still is that I added a 1500 watt heating element. I control it with the router speed controller method. (The reason for this is stated above in reference to stilling location.)

[ranger_ric]

Emow

You put a LOT more sugar in your UJSSM than I ever have.. Not sure what kind of still you run and shy the thermometer is sooooo important.. That coming from a potstill guy who believes it is what it is...

Perhaps you might freshen up and take a gander at the link in my signature to Cranky's spoonfeeding thread.. It will all work out in the end, trust me as this is coming from a pot still guy and I believe it is what it is...

Carry On
RR

[emow54]

Ranger...is the short answer that, it is what it is?

The thermometer was part of the original build. It's easier to keep it than to rebuild. And since it's there, why not use the data? I like to refer to it after feeling the cooper to see where the vapor is.

My main question is, does atmosphere have a large effect? I found some threads that talked about tenths of degree, not 20. If my previous runs were indoors (average 72 degrees) and todays run was in a different environment and almost 90 would it make that large of a difference? My gut tells me no, and that something else is different.

BTW...thanks for the link. I have already read that thread 4 or 5 times. One more could not hurt.

[NZChris]

Where is the thermometer? If it's in the wash it is telling you something useful. If it's in the top, there are too many variables that affect it, so it's only really useful for telling you when the vapor reaches it.

[pulsetech]

its only going to shorten your heat up time if its warmer outside if that is what your asking. fractions boil off at their own boiling points. that's why we make cuts.
If your talking about column temps and you have a Bi metal type thermometer just totaly disregard what is says. they can be off by miles even if it was right yesterday

[Danespirit]

Today, the temperature was 20 degrees (191 F) higher at the beginning of production. It used to kick off around 175F. Can/will humidity, temperature, etc. cause that large of a swing in temperature? I fully understand and practice touch and feel over gauges and timing, but curiosity has gotten the best of me.

Yes those factors will have influence on your run.
The reasons are:
If you lower the atmospheric pressure, the boilingpoint of the substances in your still-charge will also lower.
If you draw off all the air inside your still and distill with almost vacuum (can't get there), you might see your charge boil at 40 C.
Humidity is also a factor, but will play a bigger role in dilluting your product if you run a refluxstill with high ABV output.
Under normal conditions however, those factors play a very minimal role.
I would worry more about insulating that still, if i where to distill under cold conditions.

[still_stirrin]

After a couple of years...I decided to dust off the rig...I did a basic water run...a vinegar run, followed by a sacrificial run...

Today, the temperature was 20 degrees (191 F) higher...It used to kick off around 175F. Can/will humidity, temperature, etc. cause that large of a swing in temperature?

I used to work...on the stovetop...this time, I worked in the garage.

My sacrificial wash today wash 20-25% ABV...My UJSSM washes...around 12-14%...The only modification I made to my pot still is that I added a 1500 watt heating element. I control it with the router speed controller method...

From this input, I'd suspect that your thermometer is misbehaving. Pull it an check it in an ice water bath and in a small pan of boiling water. My suspicion is because of the moratorium between thr UJSSM runs and your most recent mods and subsequent sacrificial run: something has aged and failed. (what type of thermometer is it...bi-metal or alcohol)

As you've speculated, the higher %ABV wash you recently used in the sac run should've shown a slightly LOWER boiling temperature. However, you measured a significantly higher temp (by 20*F). That makes me suspicious of equipment error.

On a side note, your rangetop and your new (internal) element are both approximately the same BTU rating, although one is internal and the previous was external. That wouldn't cause a change in the boiling temperature, only the rate of production...how fast the heat is added affects how fast the vapor comes out of the (liquid) wash....not the temperature at which it does. As you know, the composition of the wash affects the temperature.

And as others have said, atmospheric conditions can affect the saturation temperature of your boil, but certainly not to the extreme you observed. Again, it sounds like a tempermental thermometer....hmmmmm, that sounds poetic, doesn't it?

Check your thermometer and see if that's the culprit.
ss

[yakattack]

What kind of thermometer? Hasn't been used in quite some time to me reads faulty thermometer. Check it against boiling water for your atmospheric pressure.

Yak

Posted same time as ss

[Hound Dog]

Check this post out. Don't think it applies to a pot still though.....
http://www.homedistiller.org/forum/view ... =1&t=53536" onclick="window.open(this.href);return false;" rel="nofollow

[emow54]

Thank you to everyone for your insight. I will do another equipment check and test run. When I figure it out, I'll let you know.