Monitoring temperature above the condenser.

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Dunkydonuts
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Monitoring temperature above the condenser.

Post by Dunkydonuts »

Is there logic in placing an additional thermometer above the condenser in a boka still?

My thinking is that this could monitor the performance of the condenser providing warning of any vapor escape but also allowing fine tuning of the condenser flow rate.

I am a novice, planning my first build and have read that flow rate should be slowed to be a point where the returning water is hot but still knocking out all the vapor.

It seems to me that in theory a thermometer placed in a point where any leaking vapors mix with ambient temperature air would give a very precise indicator of the point where the condenser is struggling and therefore flow rate could be tuned until the temperature reading drops.

It also seems like a more scientific method than standing on a chair hovering over a hot still holding a mirror.

Would this work in practice?
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Yummyrum
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Re: Monitoring temperature above the condenser.

Post by Yummyrum »

I recon most of the condensing is done by halfway uo the condenser . The top half is just a safety net .

Now , you could tweak water flow so the last poofteenth of vapour collapses in the last coil …. But I think it is pushing things too close to unsafe limits .

So yes , I think a top monitoring thermometer isn’t necessarily a bad thing . Shit always has ,and will continue to happen and any alert to escaping vapour is a great thing … but…. I don’t think that it should be added purely as an adjustment metric . Thats just asking for trouble .

If I was to contemplate that , I would have temp probe perhaps a 1/2 to 1/3 from the top so there was still a decent safety margin .

And also regarding excessive coolant flow and overcooling of still head and packing , it has to be really bad to be bad .
Certainly on my setup , I find that the coolant flow through a double helix coil is slowed enough naturally that it's never been a problem . Maybe if I was in city mains pressure , I may have to consider it a bit more .
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Saltbush Bill
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Re: Monitoring temperature above the condenser.

Post by Saltbush Bill »

Personally Id recommend using your fingers and eyes to see what is happening at the top of the column.....they dont need batteries to work and cant stop working half way through the job.
You could need a step ladder on site though if the reflux column is a decent length.
Dunkydonuts
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Re: Monitoring temperature above the condenser.

Post by Dunkydonuts »

Thanks Yummyrum, that makes a lot of sense. Redesigning the coil to place a temperature probe halfway in the condenser would probably be a lot of work because you need to make sure it’s measuring the vapor rather than maybe touching the coil.

Certainly a temperature alarm on the top seems sensible though. The more safety the better.
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NZChris
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Re: Monitoring temperature above the condenser.

Post by NZChris »

I put a thermometer above the Bokakob so that I can keep an eye on the temperature for if the cooling water fails.

I've recently bought some cheap temperature switches and alarms with flashing lights and buzzers that can be used for a variety of purposes around my distillery, so will use one of them at the top of my Bokakob next time it runs.

A latched relay that triggers shutdown if anything causes the temperature to rise above a set point is a safer idea, as that will keep your family safe, even if you drop dead.
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bunny
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Re: Monitoring temperature above the condenser.

Post by bunny »

Dunkydonuts wrote: Mon May 23, 2022 11:54 pm Is there logic in placing an additional thermometer above the condenser in a boka still?

My thinking is that this could monitor the performance of the condenser providing warning of any vapor escape but also allowing fine tuning of the condenser flow rate.

I am a novice, planning my first build and have read that flow rate should be slowed to be a point where the returning water is hot but still knocking out all the vapor.

It seems to me that in theory a thermometer placed in a point where any leaking vapors mix with ambient temperature air would give a very precise indicator of the point where the condenser is struggling and therefore flow rate could be tuned until the temperature reading drops.

It also seems like a more scientific method than standing on a chair hovering over a hot still holding a mirror.

Would this work in practice?


This works great as an early warning device.
The probe is almost 6" long and I stuffed it through a cork that fits the end of the condenser so it doesn't touch the coils.
It's a 40" type probe plugged into a polder scan-rite oven thermometer with a loud alarm. The thermometer stays on until you turn it off.
P1050295.JPG
P1050297.JPG
The Scan- Rite thermometers are currently out of production, however they can be found new sometimes on eBay.
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Salt Must Flow
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Re: Monitoring temperature above the condenser.

Post by Salt Must Flow »

I installed a thermowell in the reflux condenser's outgoing line so I can monitor the water's outgoing temp using a digital thermometer with an alarm set for 140F or so. I control the water flow using a small needle valve. If for whatever reason the water temp alarm sounds off, I know to open the valve a bit and I can see where the temp eventually stabilizes. On a home well water system, pressure/flow can fluctuate for many reasons so the temp will go up and down. I find it more helpful to control the water temperature so I can tune the condenser to use less water. As you learn your still, you'll also learn approx what temp the water can reach before you know vapor will soon escape. I know some say, "just feel it or feel the water as it exits". There's many other ways to determine if the water is too hot, but a simple digital thermometer that I can see and an alarm that I can hear is more convenient to me than climbing a ladder or playing with the hoses to feel the water temp.

I installed a thermowell on the outbound line on my shotgun condensers too. This could be considered excessive, but find it also convenient since my digital thermometer has 2 probes and I can set 2 alarms. One for the reflux condenser and one of for the product condenser. It's not complicated at all and it gives me the ability to tune the condenser for minimal water use and accurate repeatability. I even monitor my boiler temp during heat-up.

You don't NEED thermometers to monitor the water, but it is something I have added to my condensers over time and I really appreciate it. A lot of people do not encourage thermometers because a lot of new distillers 'think' that they can run their stills based on temp using digital thermostats/temp controllers.
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Bushman
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Re: Monitoring temperature above the condenser.

Post by Bushman »

Here is a similar thread but I was actually looking for the thread that deals with placing in before or after the PC.
viewtopic.php?f=50&t=73655&p=7554152&hi ... r#p7554152
StillerBoy
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Re: Monitoring temperature above the condenser.

Post by StillerBoy »

Salt Must Flow wrote: Tue May 24, 2022 7:20 am I installed a thermowell in the reflux condenser's outgoing line so I can monitor the water's outgoing temp using a digital thermometer with an alarm set for 140F or so. I control the water flow using a small needle valve.
The water outlet side of the condenser - best location on a reflux condenser to monitor the efficiency of the condenser during a run, and operated with a needle valve.. also, during the run, vapor temp will raise some as the depletion of the alcohol occurs, and the RC outlet will indicate that if it is setup right..

Mars
" I know quite certainly that I myself have no special talent. Curiosity, Obsession and dogged endurance, combined with self-criticism, have brought me to my knowledge and understanding "

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drmiller100
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Re: Monitoring temperature above the condenser.

Post by drmiller100 »

bunny wrote: Tue May 24, 2022 6:59 am
Dunkydonuts wrote: Mon May 23, 2022 11:54 pm Is there logic in placing an additional thermometer above the condenser in a boka still?

My thinking is that this could monitor the performance of the condenser providing warning of any vapor escape but also allowing fine tuning of the condenser flow rate.

I am a novice, planning my first build and have read that flow rate should be slowed to be a point where the returning water is hot but still knocking out all the vapor.

It seems to me that in theory a thermometer placed in a point where any leaking vapors mix with ambient temperature air would give a very precise indicator of the point where the condenser is struggling and therefore flow rate could be tuned until the temperature reading drops.

It also seems like a more scientific method than standing on a chair hovering over a hot still holding a mirror.

Would this work in practice?


This works great as an early warning device.
The probe is almost 6" long and I stuffed it through a cork that fits the end of the condenser so it doesn't touch the coils.
It's a 40" type probe plugged into a polder scan-rite oven thermometer with a loud alarm. The thermometer stays on until you turn it off.P1050295.JPG


P1050297.JPG

The Scan- Rite thermometers are currently out of production, however they can be found new sometimes on eBay.
If things go bad and the cooling water shuts off will the cork come out easily or will your still explode?
Now I know how you claim azeo so easy, it's based on a meat thermometer. :lol:
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bunny
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Re: Monitoring temperature above the condenser.

Post by bunny »

drmiller100 wrote: Tue Jul 26, 2022 4:56 pm
bunny wrote: Tue May 24, 2022 6:59 am
Dunkydonuts wrote: Mon May 23, 2022 11:54 pm Is there logic in placing an additional thermometer above the condenser in a boka still?

My thinking is that this could monitor the performance of the condenser providing warning of any vapor escape but also allowing fine tuning of the condenser flow rate.

I am a novice, planning my first build and have read that flow rate should be slowed to be a point where the returning water is hot but still knocking out all the vapor.

It seems to me that in theory a thermometer placed in a point where any leaking vapors mix with ambient temperature air would give a very precise indicator of the point where the condenser is struggling and therefore flow rate could be tuned until the temperature reading drops.

It also seems like a more scientific method than standing on a chair hovering over a hot still holding a mirror.

Would this work in practice?


This works great as an early warning device.
The probe is almost 6" long and I stuffed it through a cork that fits the end of the condenser so it doesn't touch the coils.
It's a 40" type probe plugged into a polder scan-rite oven thermometer with a loud alarm. The thermometer stays on until you turn it off.P1050295.JPG


P1050297.JPG

The Scan- Rite thermometers are currently out of production, however they can be found new sometimes on eBay.
If things go bad and the cooling water shuts off will the cork come out easily or will your still explode?
It's a 2" spool and a 1" cork. The cork just rests loosely up at the top of the spool. The cork is big enough to keep the probe from touching the spool. If the coolant shuts off the vapor will set off the alarm almost instantaneously.
drmiller100
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Re: Monitoring temperature above the condenser.

Post by drmiller100 »

bunny wrote: Tue Jul 26, 2022 6:40 pm
drmiller100 wrote: Tue Jul 26, 2022 4:56 pm
bunny wrote: Tue May 24, 2022 6:59 am
Dunkydonuts wrote: Mon May 23, 2022 11:54 pm Is there logic in placing an additional thermometer above the condenser in a boka still?

My thinking is that this could monitor the performance of the condenser providing warning of any vapor escape but also allowing fine tuning of the condenser flow rate.

I am a novice, planning my first build and have read that flow rate should be slowed to be a point where the returning water is hot but still knocking out all the vapor.

It seems to me that in theory a thermometer placed in a point where any leaking vapors mix with ambient temperature air would give a very precise indicator of the point where the condenser is struggling and therefore flow rate could be tuned until the temperature reading drops.

It also seems like a more scientific method than standing on a chair hovering over a hot still holding a mirror.

Would this work in practice?


This works great as an early warning device.
The probe is almost 6" long and I stuffed it through a cork that fits the end of the condenser so it doesn't touch the coils.
It's a 40" type probe plugged into a polder scan-rite oven thermometer with a loud alarm. The thermometer stays on until you turn it off.P1050295.JPG


P1050297.JPG

The Scan- Rite thermometers are currently out of production, however they can be found new sometimes on eBay.
If things go bad and the cooling water shuts off will the cork come out easily or will your still explode?
It's a 2" spool and a 1" cork. The cork just rests loosely up at the top of the spool. The cork is big enough to keep the probe from touching the spool. If the coolant shuts off the vapor will set off the alarm almost instantaneously.
Oh. That makes total sense.

Thank you for clarification
Now I know how you claim azeo so easy, it's based on a meat thermometer. :lol:
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