DIY Glycol help.

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You could insulate it more if transfer maximum transfer efficiency is reached, and or lower temp of glycol chiller. Also might want to check location of chiller temp probe. If it is too close to evaporator it may give a misleading reading.
 
Theres no appreciable hazzard in operating without a cover except maybe mechanical if something strikes the fan as far as operating the compressor without a shroud over it. In fact in any other setup except an ac system where the goal is to make it portable and keep rain water out off of it, the compressor and condensor are exposed. Look at many commercial chillers like the micromatics and you will find most either have no cover or it was removed long ago by maintenance people or techs to clean the coils same with many fridge and freezer setups and remote compressor setups located above walk in coolers or in basements.

Ideally the best setup would be to reverse the fan to pull cold air in through the condensor from the outside and then blow across the compressor, this is the main difference between an ac compressor and refrigeration compressor layout from what I have read. they are laid out differently because of application and efficiency in that application to prevent the "firewall" between the hot and cold side from being bombarded with warm air and possibly wet air when it rains.

EDIT correction, quoted wrong comment.
 
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My unitank is really struggling to get to 37* it hit 37* last night in the initial crash, but since I’ve been up this morning, the pump is continuously running but it’s sitting at 37.5-38. The reservoir is getting down to 27* very comfortably so I’m not sure what the issue is. I even tried bumping the reservoir to low 30’s wondering if it was a freezing issue, but I wouldn’t think that to be the case?

All in all I’m not too concerned about it. I’m happy with 38*. But still wondering why the batch won’t go lower.
there are a lot of threads on this many cant get below 40... basically its normal. Its due to flowrate and coolant surface area as well as insulation on your unitank. you may find the coils are freezing the water in your beer to form ice around them in the unitank.

EDIT I see Vale71 already answered your question, I should have read further before answering but I second his response here.
 
This is an extreme exaggeration. Theres no appreciable hazzard in operating except maybe mechanical if something strikes the fan as far as operating the compressor without a shroud over it. In fact in any other setup except an ac system where the goal is to make it portable and keep rain water out off of it, the compressor and condensor are exposed. Look at many commercial chillers like the micromatics and you will find most either have no cover or it was removed long ago by maintenance people or techs to clean the coils same with many fridge and freezer setups and remote compressor setups located above walk in coolers or in basements.

I think he was talking about using non food safe glycol.
 
I think he was talking about using non food safe glycol.
Exactly. Ethylene glycol is really extremely toxic and should never be used but we've already established that RV antifreeze does not contain ethylene glycol so the issue is really moot.
 
Exactly. Ethylene glycol is really extremely toxic and should never be used but we've already established that RV antifreeze does not contain ethylene glycol so the issue is really moot.
yes sorry I already seen my error and corrected it before seeing there was now a second page of responses...

As stated RV antifreeze is food grade too which is why its used in potoble water pipe plumbing in rvs.

BTW foodgrade glycol is fine if used in this application for more than a year... Ive been using the same stuff at 28 degrees for 3 years with no issues. and you only need like a 30% glycol to 70% water mix for that temp...
 
My mix clearly didn’t last too long. Probably because I used half and half with distilled water. I’ll probably use the real stuff next time around.

Adjustments.JPG
 
My mix clearly didn’t last too long. Probably because I used half and half with distilled water. I’ll probably use the real stuff next time around.

View attachment 661914
half what? rv antifreeze or foodgrade glycol? is it freezing or are you saying it didnt last because its changed color? Mine doesnt look like that but I am not using a used an air conditioner evap unit in the bath either and I wonder if the discoloration has come from that? I used regular tap water with much less clear food grade gycol and right now mines at 27 degrees without any freezing..
something in the RV stuff might oxidize over time or pick up the oxidation off the copper coils and cause that color change as well.
 
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RV antifreeze shouldn't be diluted. Use it full-strength. It's super-cheap.
I think over time in coolant tanks like ours, since it's not a sealed unit - we have to expect to change the liquid out from time to time (whether it's just water or a glycol solution). There are too many openings in the cut-outs of the cooler that junk can get in. In my garage, I often have sawdust floating around in the air, vehicle exhaust, paint or solvent vapors, etc. And that's in addition to all the bugs and bacteria just naturally occurring.
I'm expecting to have to change mine at least once per year -
 
I’m saying that mostly based on the color of the bath. The original photos I posted showed a really vibrant red and it was crystal clear. Now it’s lost most of its color and it’s kind of murky.

I’ve been keeping my glycol at about 30* and it’s worked great at that temperature.

I did expect it to go bad, just not as fast as it did. This is about the 6 month mark for me. I also did not fill the gap around the copper lines going into the cooler. So mine has slightly more exposure to the air around it.

This has overall been a very positive experience and I highly recommend it, I was just posting my results using the RV antifreeze for any future readers.
 
If I recall, you said you did not clean the coil before starting it up. That could easily explain the first batch getting dirty. I suspect your second round would stay looking good longer.
 
If I recall, you said you did not clean the coil before starting it up. That could easily explain the first batch getting dirty. I suspect your second round would stay looking good longer.

That is true, I did not and very well may be the case. Maybe I’ll flush it out, give everything a rinse and try again.
 
If you're going to use RV type PG antifreeze don't use the kinds that have alcohol in them since it evaporates quite fast.
Use something like these:
https://www.westmarine.com/buy/west-marine---100-f-engine-water-system-antifreeze-gallon--363798
https://www.westmarine.com/buy/star...centrated-antifreeze-antigel-gallon--14823355

I use it in my boat's potable water system.

Yeah, I don't know.

Anti-corrosion additives? Yummy! The label on the anti-freeze I use in my RV lists several things other than "food grade" propylene glycol. Non-toxic just means, in simple terms, that it probably won't kill you if you ingest it. Will it give you stomach cramps or diarrhea? Depending on how much you consume, quite possibly (think 'Epsom salts').

Sure, the temptation is to use "non-toxic" RV/Marine anti-freeze at $3.50 a gallon in place of "food grade" pure propylene glycol at $30 per gallon. But RV guidelines say to completely flush and sanitize the potable water system when de-winterizing in the spring. That means the fresh tank as well as the water supply lines. Now we just use the fresh tank for washing and flushing, and R.O. for cooking and drinking, but I still flush the tank completely in the spring to eliminate propylene glycol.

Just because something is "non-toxic" doesn't mean it's 'safe' for consumption without consequences. Even airlines are under pressure for using propylene glycol based de-icing fluids since run-off is affecting groundwater near airports. Although "non-toxic", it's something you want to not accidentally get into your food and beverage pipeline.

Brooo Brother
 
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I would argue that I wouldn’t want glycol that has been sitting in a reservoir for years to get into my beer either. Especially after swishing around coils of a torn apart air conditioner. Is it really still food grade at that point?

With that being said, there is 0% chance that any of this gets into my beer. I don’t even attach or detach the lines when the system is open so there really is no chance. Now I wouldn’t use something that’s blatantly toxic of course, but I’m not worried about RV antifreeze.

If any containment got into my beer, glycol, RV antifreeze, any of my cleaning chemicals, I would not drink that beer nor would I serve it to any of my friends.
 
Yeah, I don't know.

... Although "non-toxic", it's something you want to not accidentally get into your food and beverage pipeline.

Sure, but that's up to the OP to decide on the probability of it leaking. And just think the Anti-corrosion additives will protect the glycol chiller parts.
 
Yeah, I don't know.

Anti-corrosion additives? Yummy! The label on the anti-freeze I use in my RV lists several things other than "food grade" propylene glycol. Non-toxic just means, in simple terms, that it probably won't kill you if you ingest it. Will it give you stomach cramps or diarrhea? Depending on how much you consume, quite possibly (think 'Epsom salts').

Sure, the temptation is to use "non-toxic" RV/Marine anti-freeze at $3.50 a gallon in place of "food grade" pure propylene glycol at $30 per gallon. But RV guidelines say to completely flush and sanitize the potable water system when de-winterizing in the spring. That means the fresh tank as well as the water supply lines. Now we just use the fresh tank for washing and flushing, and R.O. for cooking and drinking, but I still flush the tank completely in the spring to eliminate propylene glycol.

Just because something is "non-toxic" doesn't mean it's 'safe' for consumption without consequences. Even airlines are under pressure for using propylene glycol based de-icing fluids since run-off is affecting groundwater near airports. Although "non-toxic", it's something you want to not accidentally get into your food and beverage pipeline.

Brooo Brother
You know the antifreeze does not mix with the beer right? (I'm kidding) but seriously... I dont know what kind of cooling solution your using at the fermenter end but there should be no chance of the stuff getting in your beer. if it did your would have contaminated and very likely infected beer.

the ac unit condenser consists of aluminum and copper.... all things people put in contact with food quite often. I wouldnt want the antifreeze in my beer but I dont have any chance of that ever happening with my cooling jacket being on the outside of my conical without fittings on the lid connecting coils that are immersed in the beer. That said I still ponied up $30 for a gallon of food grade glycol myself Ive been using for years now..
 
So what is the assumption here? That something like 500ml leaks into 20 liters of wort? Add a jar of blue cake icing coloring to the glycol mix and if your beer is blue something is wrong. If you don't know that it's leaking you already have a serious contamination problem food grade glycol or not.
 
You know the antifreeze does not mix with the beer right? (I'm kidding) but seriously... I dont know what kind of cooling solution your using at the fermenter end but there should be no chance of the stuff getting in your beer. if it did your would have contaminated and very likely infected beer.

the ac unit condenser consists of aluminum and copper.... all things people put in contact with food quite often. I wouldnt want the antifreeze in my beer but I dont have any chance of that ever happening with my cooling jacket being on the outside of my conical without fittings on the lid connecting coils that are immersed in the beer. That said I still ponied up $30 for a gallon of food grade glycol myself Ive been using for years now..

Being jacketed, there is even less chance obviously of contact with the contents inside your fermenter. What's the probability of a leak in an immersion coil inside the fermenter? Greater, but still reasonably 'slight.' Still I, like you, opt in favor of a product deemed "food grade" over something listed as "non-toxic." I suppose I could buy an extra pound of hops with the $26 savings. So I'd be spending $$$ on a quality hop but skimping on another brewing item? No thanks, I'll go with quality on both ends.

If I wanted to save money on beer, I would have quit home brewing years ago and bought 6 packs off the shelf instead. For me it's all about the quality I perceive and the satisfaction I derive.

Brooo Brother
 
I used a many year old A/C unit that had caked on lint/dirt on the fins. Washed it off best I could, used a toothbrush to try and get the dirt out. The first couple times using it the water got really dirty, and gradually less so with each use.
My main concern was for gunk to get in the aquarium pump and stop it from pumping. I've just come to the conclusion that it's going to get dirty. When there are too many bugs/chunks in the tank/cooler, I'll drain it and start over. In fact, I've never even used Glycol/Antifreeze yet. I've only used water and can get the coolant temp down to about 35-37F with just water. And - it's heating season here in MN. I only have to use the chiller 4-6 months out of the year anyway.

I don't connect the hoses with the cover on the fermenter so should be pretty safe.
 
So what is the assumption here? That something like 500ml leaks into 20 liters of wort? Add a jar of blue cake icing coloring to the glycol mix and if your beer is blue something is wrong. If you don't know that it's leaking you already have a serious contamination problem food grade glycol or not.

I'm not sure that's all you get . It would depend on your temp. If my tubing had a crack and the pump kicked on because it was warm it would dump glycol until the desired temp was met and turned off the pump. I guess it would also depend on how often your pump kicked on .
 
So what is the assumption here? That something like 500ml leaks into 20 liters of wort? Add a jar of blue cake icing coloring to the glycol mix and if your beer is blue something is wrong. If you don't know that it's leaking you already have a serious contamination problem food grade glycol or not.

Well at least food coloring or blue cake icing are "food grade" and edible, designed for human consumption.:)

Brooo Brother
 
To each their own, but the debate over glycol and rv antifreeze is really a non issue for me. If you read my comment that got this thread going today, I advised that I was considering legit PG anyways. Not because I’m afraid of death, or an upset stomache, but because it may be a more stable mix in my cooler. Maybe not.

With that being said, the savings is much greater than $25. With the bulky cooler, and the way the coils are, I think I have about 10 gallons in there. Even if I went 3 to 1, I’m looking at near $100 in glycol compared to maybe $10 in RV antifreeze. It’s not a matter of being cheap, your right, if I wanted to save money I would quit brewing. I’m using an SS Unitank and a spike kettle, I’m doing this for fun, not to save money. However, I will reasonably cut cost where I can for something like that.
 
fwiw i don't have any problem using the -100 PG in a glycol cooler that I'm building out of an old AC unit. The stuff in the AC coil is much more dangerous than the non toxic PG antifreeze.
 
And to be pedantic would you drink that?
no I never have to worry about it either... but lets say there was some situation where I did... no big deal its food grade glycol and water... same stuff they use as the main ingredient of vap juice... and the beer would kill anything that would make me sick so... no worries.
 
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fwiw i don't have any problem using the -100 PG in a glycol cooler that I'm building out of an old AC unit. The stuff in the AC coil is much more dangerous than the non toxic PG antifreeze.
I get what your trying to say here but to be realistic, Do you think that the coolant would somehow end up in the antifreeze while the chiller still works? DIY ac unit or not all chillers use the same components and refrigerant as thier air conditioner counterparts of the same age and at the same time that coolant would also leak into your beer? those are some odds..... If you bought a penguin chiller they are even made from a window air conditioner, just not at home..
 
To each their own, but the debate over glycol and rv antifreeze is really a non issue for me. If you read my comment that got this thread going today, I advised that I was considering legit PG anyways. Not because I’m afraid of death, or an upset stomache, but because it may be a more stable mix in my cooler. Maybe not.

With that being said, the savings is much greater than $25. With the bulky cooler, and the way the coils are, I think I have about 10 gallons in there. Even if I went 3 to 1, I’m looking at near $100 in glycol compared to maybe $10 in RV antifreeze. It’s not a matter of being cheap, your right, if I wanted to save money I would quit brewing. I’m using an SS Unitank and a spike kettle, I’m doing this for fun, not to save money. However, I will reasonably cut cost where I can for something like that.
Well to be truthful I have an 10 gallon sump in my chiller at the brewpub... I have one and a half gallons of food grade antifreeze which cost $45 on amazon mixed with tap water... chiller is set for 28 degrees and doesnt freeze up.. A gallon of FG glycol is $30 shipped on amazon and goes a lot further than rv antifreeze..
 
Being jacketed, there is even less chance obviously of contact with the contents inside your fermenter. What's the probability of a leak in an immersion coil inside the fermenter? Greater, but still reasonably 'slight.' Still I, like you, opt in favor of a product deemed "food grade" over something listed as "non-toxic." I suppose I could buy an extra pound of hops with the $26 savings. So I'd be spending $$$ on a quality hop but skimping on another brewing item? No thanks, I'll go with quality on both ends.

If I wanted to save money on beer, I would have quit home brewing years ago and bought 6 packs off the shelf instead. For me it's all about the quality I perceive and the satisfaction I derive.

Brooo Brother
This might sound cocky but I guess I could take some of the hundreds of dollars I saved by using $60 of blue discharge hose from the home depot to cool my fermenters as jackets instead of spending hundreds more for pain in the ass coils which have drawbacks like these as well as cleaning inconveniences.. To be fair I use coils at the brewpub untill my new unitanks arrive that we ordered... They work well but I still hate them... In fact I accidently took 93gallons of beer down to 34 degrees while lagering another 90+ gallons at 50 and holding yet another at 65 degrees all with a little 1/3hp chiller set at 28 degrees so I am amazed that some buy such huge chiller to control temps on a single little 8 or 14 gallon conical and worry it wont be enough. Granted the huge conicals being made of plastic helps when bringing temps down with a coil vs stainless but the plastic is also why the hose wont work wrapped around the outside.
 
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