How useful is boiler temp? Whenever I’m at the vapor point I see nothing

[HuckFinn]

Hi everyone,

One thing I’ve noticed is in order to get a vapor temp you need vapor (not a surprise), but the boiler temp almost always needs to be well above the vapor point of ethanol even to see foreshots.

Is there something I am not understanding here? Folks say “collect until X temp your foreshots, heads, etc.” But I’m not seeing anything until my boiler is at least 180F / 83C.

If I’m trying to kick off foreshots what boiler temp should I be aiming for? Particularly if I’m doing a reflux.

Thanks

[still_stirrin]

Where’s your thermometer? In the vapor path, or the boiler?

Chances are, the boiler charge doesn’t have as much alcohol as you think....if you think.

We’ve said it over and over in these forums...you can’t run a still by temperature. The fact that you “throw out” questions without reading is approaching trolling. Please, and I ask nicely, READ the mandatory threads all the way through. You will find the answers to your questions before you have to ask.

Here’s an important thread to start with: https://homedistiller.org/forum/viewtop ... 65&t=16635

Please make the website a tool, not a crutch. Help yourself and you’ll find much more knowledge than a “shotgun of questions”, all of which have been asked and answered many times before.
ss

[Saltbush Bill]

Folks say “collect until X temp your foreshots,

Who are these folk who say that?....... my guess is that they are not from this forum but are those on youtube or else where.
People here would not give you that advice because they know that you cant control boiler temp......nor is trying to run a still by temp a good idea.

[tubbsy]

The temperature of both the boiler and vapour are determined by the alcohol content in each., but not in the same way. This chart shows the relationship in vapour and liquid of temperature vs ABV.

[Yummyrum]

The boiler temp will be pretty close to the Vapour temp in the head space of the boiler .

There was an initial lag at the start as the head space was purged of air and replaced with vapour . That typically took about the time to take off foreshoots. After that , the temps follow each other .

However I found that a Rum wash boiled at a slightly higher temp than its resultant vapour . This I put down go the salts present in the wash from the Mollases raising the boiling temp .

[shadylane]

Is there something I am not understanding here? Folks say “collect until X temp your foreshots, heads, etc.” But I’m not seeing anything until my boiler is at least 180F / 83C.

Try raising the boiler temp to 100C
At first the temp will rise rapidly to whatever temp the wash boils at.
For instance with 10% abv in the pot, it will start boiling @93C
As the alcohol boils off the temp will slowly climb.
Some were around 100C the boiler temp will stop rising.
And remain at that temp until the water boils off or the heating element goes up in smoke.

[zed255]

Either way Yummy, the OP appears to be badly misinformed or uninformed about how the process of distillation works. Huck appears to believe that at a certain temperature of the boiler charge that specific fractions would be liberated, which the standing membership knows to be incorrect.

Huck, the mixture in the boiler boils at whatever temperature its composition dictates and that changes as the composition changes. You can not dial up a specific temperature and just extract certain components. I'm not a chemist or physicist and can't give you a detailed explanation, but I know this to be fact.

The temperature of the boiling mixture will give an indication its possible alcohol content.
The temperature of the vapour, in particular just before it enters the condenser, is an indicator of the vapour alcohol content.
See the alcohol water phase diagram already posted above.

[Justinthunder]

My still came with a temp gauge but I don’t even look at it, make sure your flame isn’t going to be too hot too fast and burn anything and the alcohol comes when it comes and it finishes when it finishes, not a process you can rush nor should you, I always collect the first 3/4 jar of fores and keep it for fire starter, the next jar is for my next batch, the rest is for tasting and cuts

[GNBrews]

Where’s your thermometer? In the vapor path, or the boiler?

Chances are, the boiler charge doesn’t have as much alcohol as you think....if you think.

We’ve said it over and over in these forums...you can’t run a still by temperature. The fact that you “throw out” questions without reading is approaching trolling. Please, and I ask nicely, READ the mandatory threads all the way through. You will find the answers to your questions before you have to ask.

Here’s an important thread to start with: https://homedistiller.org/forum/viewtop ... 65&t=16635

Please make the website a tool, not a crutch. Help yourself and you’ll find much more knowledge than a “shotgun of questions”, all of which have been asked and answered many times before.
ss

It might be time for some folks to stop hanging out in the novice section if they're getting triggered by novice questions. This is the place for those questions; we have folks that are patient enough to respond to them without being hostile.

[howie]

my easy answer is, occasionally when i gaze in the general direction of the boiler temp during a reflux spirit run, the temp of the charge is usually around the 83/84C mark at the beginning of the run.
i don't aim for any temp, that's what my boiler temp shows when the first product comes off, i have no control over this temp.

[8Ball]

For trivia purposes, my 5G copper pot & 1.5” riser starts to produce fores at 198F pot temp during a stripping run. Sometimes at a little lower temp during a spirit. In both cases, I smell them in the air shortly before the drip starts.

To answer your question, heat up slowly and when you start seeing the first drips (this occurs around 140F vapor temperature just before the condenser) back off your heat to get a small drip going. Hold the slow drip as long as you can, it will noticeably speed up at 172F, then you can increase the heat and finish collecting fores.

I usually don’t collect fores during stripping runs since I make very narrow heart cuts during AG spirit runs. For sugar heads, I do.

[6 Row Joe]

Hi everyone,

One thing I’ve noticed is in order to get a vapor temp you need vapor (not a surprise), but the boiler temp almost always needs to be well above the vapor point of ethanol even to see foreshots.

Is there something I am not understanding here? Folks say “collect until X temp your foreshots, heads, etc.” But I’m not seeing anything until my boiler is at least 180F / 83C.

If I’m trying to kick off foreshots what boiler temp should I be aiming for? Particularly if I’m doing a reflux.

Thanks

Never had a boiler thermometer and you don't really need one. I used to monitor the temp at the top of the column but it was a waste of time. Each run is different, each boiler charge is different. Get to know your equipment by sound, feel the temp, and regulate it by the rate the product leaves the condenser.
Just like making cuts, go by smell, taste and feel.

[howie]

now i only use the boiler temp to remind me to turn the water pump on.
i don't use temp gauges on a stripping run any more.
i now use 2 x temp gauges just at the very start of a reflux spirit run (one either side of the RC) to confirm that i am in full reflux & the RC is 100%, and then the little change when EQ is starting.
after starting to take product off on a spirit run, temps are not used.
but this takes time to learn, but i can see my early notes when i was infatuated with temps.

[NZChris]

Asking about boiler temperature without telling us where your probe is will usually fetch you a variety of answers, most of them unhelpful, but all given with good intentions.

Temperatures at various points in a still at any given stage of a distillation vary widely for a variety of reasons.

If you disregard all of the temperature answers, double distill and use your taste buds to select your cuts, it's quite difficult to make bad product from a nice wash.

[Yummyrum]

If I’m trying to kick off foreshots what boiler temp should I be aiming for? Particularly if I’m doing a reflux.

Huck , I can see why newbs get confused . Sorry , I missed the point that you were talking about a reflux still and here I was and several others , giving info and advise about Pot stills .

OK , well as the others have said , the boiler will boil at whatever temp relates to the mix in it .
Incidentally , if you look at Tubby’s chart you can see that you must have had @45%abv in the boiler if it was boiling at 83°C

Now you are talking about a reflux still . If you leave it in full reflux , the foreshots will work their way to the top of the column due to the refluxing action in the packing .

The temp at the top of the packing will be close to the temp of the foreshots even though the boiler temp is much higher . There is a temp gradient up through the packing . ( this is due to the many many redistilations that are happening as the vapour moves up ... and the reflux works back down to the boiler)

The boiler temp may be at 90°C , but the temp at the top will be close to 78.3°C when the pure ethanol is coming off .

Its the packing and the reflux that does all the magic . All you have to do is stick as much vapour into the column as it can take before it floods and choose how fast you want to take off product . That is all you can control and it has nothing to do with temp .

Now I said that the temp at the top will be 78.3°C when you are taking off pure ethanol . If you take off product at a faster speed , there is less reflux so the Purity will drop
and therefore the temp will go up . . ( because you will no longer be just taking off pure ethanol)

At the end of the day , you are in charge of how quickly you want to make spirit and as a result of that , the quality of it .

The temperatures merely reflect the result of that .

[NZChris]

Particularly if I’m doing a reflux.

I missed that. The distillation being a reflux isn't a minor detail Please disregard my post.