Sight Glass a Risk?

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kmk1012

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I was thinking of adding a sight glass to my keggle but, after thinking about it, I declined. It would be easy to use except I would be worried about the volume of unboiled wort that you are always "seeing" getting drained into the fermenter post boil. Maybe my concept is wrong, I would love to have one but don't want to risk any infections. Has anyone had or expirienced any issues with them? How do you fix them.
 

snccoulter

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I honestly think the wort you see will be at or near the same temp as the wort in the keg just because of the heat transfer, but I don't have one yet
 

Dan

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Understand your concern but there is nothing to worry about. During brewing the wort inside the sight glass is either as hot as the wort inside the brewpot or very close to it. It looks like it is boiling if it isn't is very hot and hot enough to sanitize.

Never had a problem. Many, many home brewers use sight glasses with no problems.
 

Formito

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I thought about that a little at first too, but you can actually see small bubbles form and rise in the sight glass. It shouldnt be a problem
 

Cromacster

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Does this hold for electric also? With gas you will get heat up around the side of the kettle.
Shouldn't matter. If there was enough heat up the side of the kettle to boil the water in my sight glass...the tube would most likely melt.
 

Bobby_M

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I suppose there are two scenarios to consider (electric vs gas and if you chill in place or run it out). If your kettle is electric, the sight glass wort will be cooler than if you run gas, but I'd really be curious to know how cool that wort stays during a boil. Anyone care to drop a digital probe down there to check?

Let's say for giggles that it only gets to 170F for an HOUR. Not much will live through that.

If you use an IC to chill in place, I see what you mean about that 1 ounce of wort that only hit 170F for an hour. If there's even a remote risk of something living through that, the easiest way to flush that cooler wort would be to just hold a short piece of hose to the top of the glass and blow into it. That pushes it into the boil and let's boiling wort enter the tube. This would be an absolute guarentee but total overkill in my opinion.

In the case of a external chilling operation like CFC or plate exchanger, it's completely irrelevant. The small volume of sight glass wort integrates into a 212F blood bath ;-)

If sight glasses caused infections, I'd be out of business.
 

samc

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In my case, a single vessel BIAB set up using the Bobby M sight glass you will see the wort at a certain color & opacity during the mash. By the time the boil is done it has completely changed and looks like a wort that has been boiled. I don't sit and watch the progression, only the results. Stop worrying and buy one.
 

Cromacster

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If you use an IC to chill in place, I see what you mean about that 1 ounce of wort that only hit 170F for an hour. If there's even a remote risk of something living through that
Even so, I'd be super surprised if the wort in the sight glass was the same at the beginning of the boil as at the end of the boil. With the amount of motion that boiling liquid goes through I would think the wort cycles through the sight glass throughout the duration of the boil.
 

Bobby_M

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Stop worrying and buy one.
Yes, buy one.

:ban: You realize my participation in this thread is meaningless due to conflict of interest right? Actually no, if I didn't believe a sight glass was a good addition to a brewery, I'd stop this nonsense and actually have time to brew.
 

DustBow

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Next time I brew (probably next weekend) I will stick my digital thermometer down my BobbyM sight glass at the 30 minute mark to check the temp.
Over a burner, it definitely gets very hot - I've boiled in there and had to add a heat shield.
But it would be interesting to check when I brew on the flat electric stove top.
I'm not worried about it though, it's not much liquid at all and it's still gonna be pretty damn hot
 

Hermit

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Next time I brew (probably next weekend) I will stick my digital thermometer down my BobbyM sight glass at the 30 minute mark to check the temp.
Over a burner, it definitely gets very hot - I've boiled in there and had to add a heat shield.
But it would be interesting to check when I brew on the flat electric stove top.
I'm not worried about it though, it's not much liquid at all and it's still gonna be pretty damn hot
I'd appreciate it if any electric brewers would do the same. I'm thinking about going electric soon.
 

Bobby_M

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To be as accurate as possible, preheat the metal probe in the boil for 2 seconds before dropping it into the tube. With such a tiny volume, a cold probe could drop the temp quite a bit.
 
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kmk1012

kmk1012

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Thanks for the input, I see the point that it does get very hot during the boil (I direct fire). We are getting our bonuses in a short time and that was my next addition. I guess BobbyM will be getting a little business from me!
 
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To be as accurate as possible, preheat the metal probe in the boil for 2 seconds before dropping it into the tube. With such a tiny volume, a cold probe could drop the temp quite a bit.
I'll probably drop a thermocouple lead down into tube. Very little mass there. I have a logging thermometer too, so easy peezy.
 

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If it's a concern, maybe partway through the boil exchange the liquid contained in the sightglass. Simply attaching a length of tubing to the top and blowing into it would force what's in the tube out into the kettle and, presumably, some of the boiled wort would return up the sightglass in its place?
 
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I'll do it this wkend.
Well, I decided to grill some homemade chorizo sausage links (!!!) so I filled the HLT with 10g water and dropped some thermocouples into the mix, and the results are surprising.

I'll post graphs from my thermometer later (it's still going), but it looks like the "wort" in the sight glass isn't getting above 130F.

More later.
 
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Just turned off the boil (and sausages). Boiled for at least 30 minutes. Sight glass never went above 130F (thermocouple was at ~ 8g mark out of 10g). I logged it, but I've got to upload it from gadget, etc, will take some time.

BTW, it's a Bobby_M sight glass.
 

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If it's a concern, maybe partway through the boil exchange the liquid contained in the sightglass. Simply attaching a length of tubing to the top and blowing into it would force what's in the tube out into the kettle and, presumably, some of the boiled wort would return up the sightglass in its place?
Well, after blowing into it you better hope the hot wort kills off what ya just put into the tube.
 

sudsmcgee

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I was thinking of adding a sight glass to my keggle but, after thinking about it, I declined. It would be easy to use except I would be worried about the volume of unboiled wort that you are always "seeing" getting drained into the fermenter post boil. Maybe my concept is wrong, I would love to have one but don't want to risk any infections. Has anyone had or expirienced any issues with them? How do you fix them.
Considering I have to work to keep the wort inside the sight glass from boiling over, I'd say you're fine.
 

sudsmcgee

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Just turned off the boil (and sausages). Boiled for at least 30 minutes. Sight glass never went above 130F (thermocouple was at ~ 8g mark out of 10g). I logged it, but I've got to upload it from gadget, etc, will take some time.

BTW, it's a Bobby_M sight glass.
I guess it's a matter of setup, but I know my sightglass is right near boiling at all times.

And you don't need to blow into the tube to get hot wort to go into it. All you have to do it change the kettle volume down and then back up. This could be as simple as removing a hop sack or removing some wort and adding either back. Hot wort will enter the sightglass and rise to the top. Do this a few times and your probably good to go.
 

Dan

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Just turned off the boil (and sausages). Boiled for at least 30 minutes. Sight glass never went above 130F (thermocouple was at ~ 8g mark out of 10g). I logged it, but I've got to upload it from gadget, etc, will take some time.

BTW, it's a Bobby_M sight glass.
Your'e using an electric kettle right Passedpawn? Just wondering, does the wort in your sight glass continually fill with hops and bubbles? My propane heated kettle does. Is it the same for electric?
 

Stevo2569

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Considering I have to work to keep the wort inside the sight glass from boiling over, I'd say you're fine.
+1. I had to install a blow off tube on my sight glass from day 1. It spewed out and into the air a few inches and down the kettle where the wort burned into the flames forming a black crust by the end of the boil that was very hard to scrub off.(End of Huge Run-On Sentence). Like I said press fit a 1' piece of tubing on the end and turned it back into the Keggle. Best I can tell the air bubbles build and build until enough of them form to lift about 3" of wort, then out the top. I'm very surprised that this is not that common, OR IS IT?
 
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Your'e using an electric kettle right Passedpawn? Just wondering, does the wort in your sight glass continually fill with hops and bubbles? My propane heated kettle does. Is it the same for electric?
Right Dan. I wish I could upload pics and graphs, but I'm re-installing the operating system on my PC right now, in the process of re-installing apps (and eating chorizo!)
 

Bobby_M

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Stevo2569 said:
+1. I had to install a blow off tube on my sight glass from day 1. It spewed out and into the air a few inches and down the kettle where the wort burned into the flames forming a black crust by the end of the boil that was very hard to scrub off.(End of Huge Run-On Sentence). Like I said press fit a 1' piece of tubing on the end and turned it back into the Keggle. Best I can tell the air bubbles build and build until enough of them form to lift about 3" of wort, then out the top. I'm very surprised that this is not that common, OR IS IT?
This is an overheating situation, not uncommon but its burner dependent. Use a heat shield.
 
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Just turned off the boil (and sausages). Boiled for at least 30 minutes. Sight glass never went above 130F (thermocouple was at ~ 8g mark out of 10g). I logged it, but I've got to upload it from gadget, etc, will take some time.

BTW, it's a Bobby_M sight glass.
I posted a graph and further data here:

https://www.homebrewtalk.com/f11/gr...g-boil-surprising-results-301165/#post3743284



It's a bit of a surprise. I might have to consider a change to my process actually.
 

Stevo2569

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Bobby_M said:
This is an overheating situation, not uncommon but its burner dependent. Use a heat shield.
It happens on both my HLT(with heat shield) and BK(without but, flames don't hit it).
 

HawkATP

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Did a batch this morning and put the thermometer down in the sight glass. 120 degrees measured at different points throughout the boil.
 

Hermit

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I posted a graph and further data here:

https://www.homebrewtalk.com/f11/gr...g-boil-surprising-results-301165/#post3743284



It's a bit of a surprise. I might have to consider a change to my process actually.
I appreciate your doing that. I'm planning on going electric. No site glass yet. I wondered if I was over thinking it but it appears not. I had thought sanitizer down the sight glass and then loosely capping it with aluminum foil. The reality is cleaning it is probably good most of the time but the one time it isn't is when you've made a big beer that ages for a year or more. Then little buggers have a chance to multiply and grow over time. Obviously you are at the mercy of what is in the air which may not matter 99.95% of the time.
 

Punx Clever

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In reality though... everything in the kettle has been at 150-160 for an hour to mash, then bumped up to 170 or so to mash out before it ever saw the sight glass, unless you are doing extract.

Then, unless you use an immersion chiller, it recombined with the 200+ degree worth before going through a chiller.?

I wouldn't worry about it.
 
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