G30/G40 counterflow chiller…

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Rento

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Hi,

I messed up tonight on my first G40 brew….basically I managed to pitch my yeast into 45 degree wort! A bit of a brain fart after a really smooth brew day on a really cool piece of kit!

So I set the water to around 1l per minute flow as advised and after what seemed like ages I read on my thrumomenter 21 degrees which I was looking for. But for some reason it was way out! totally My fault as I usually and should have used my digi thermometer. So it’s in the brew fridge chilling down and I’ll pitch another yeast when at the right temperature. At least it’s not going to ruin the batch.

Anyways…..how long do folk find it takes to cool a 23l ish batch to pitching temp? Is it really faster than coil chillers? I normally use the brewferm chill‘n 20 which I find really good in my Burco setup and I’m wondering if the counterflow is actually any better?

Other than that issue, I’ve been very impressed with the G40. I do need to dial in my process a bit but it’s a lovely bit of kit. Totally unnecessary though as I don’t think my BIAB is any more effort and has always made great beer! But hey you gotta love a new toy 🤗
 
length for length, a counterflow chiller is far FAR quicker than an immersion. Its high thermodynamic efficiency is because the temperature difference between the coolant and the hot fluid is maximised at all points along the pipe: at one end, fresh (cold) coolant meets partly cooled (warm) wort; and at the other end partly warmed coolant meets fresh (hot) wort. This arrangement guarantees the highest rate of heat energy transfer between the two fluids.
For example, see: Counter Flow Heat Exchangers and its Working Principles | Linquip
 
I've never measured the time (I will next time) but I would guess it probably takes me 10-15 minutes to chill/transfer 23l of wort from my g30 to the fermenter. Much quicker in winter when the tap water is a lot colder
 
I don’t even measure the temperature of the output of my chiller now. I just hold the tube and if it feels cold enough I fill the fermenter. I’ve got a glycol chiller so it chills to pitching temp very quickly if it’s a bit hot. Usually chill to around 25 with the counterflow with the valve open all the way then wait until it has chilled in the fermenter before pitching. I transfer, clean up and put everything away then pitch yeast before I’m finished.
 
Mines pretty quick but 1l/min is pretty optimistic in warm weather where the water out of your tap isn’t as cold. Don’t go mad with it but maybe try 3l/min and adjust your ball valve accordingly.
I haven’t timed mine but 15 mins in the winter, 20-25 mins in the summer is probably about what I get because I’ll restrict the flow until I hit the temp I need.
 
I’ve never timed the cooling/transfer (one to check on my next brew) but the latest addition (toy) to my Grainfather setup has been a Wortometer! Great piece of kit and very simple.
The output from the counter flow chiller flows through the Wortometer with the Grainfather temperature sensor in the Wortometer. Then adjust the pump flow to achieve the required temperature.
Happy days!
 
latest addition (toy) to my Grainfather setup has been a Wortometer! Great piece of kit and very simple.
The output from the counter flow chiller flows through the Wortometer with the Grainfather temperature sensor in the Wortometer. Then adjust the pump flow to achieve the required temperature.
Happy days!
I agree this is one of the best uses for the wortometer and is something I wouldn’t be without, even though I don‘t use a GF!
 
I did another brew last night and all was good…apart from a stuck mash but I think the recipe had a lot to do with that! The chiller worked a treat and was pretty quick, the alarm when the temp was down to 25 degrees was really handy and then I used the thrumometer to get the 20 I was looking for.

automation and alarming is really handy and allowed me to paint a bathroom at the same time as brewing, keeping my good lady happy and avoiding an ‘are you brewing again?’ Discussion!
 
I did my first G40 brew a few weeks ago and the temp dropped to 18/19° in a single pass. I had the wort flow on really slow to start but it actually cooled a lot better at around 2/3 open. The water coming out was hot!
 
Have you ever tried putting it in the fermentor (I’m presuming it’s stainless) direct and let the glycol chiller cool it?
I think that might be a bit energy intense. Also you don’t have the surface contact between the hot wort and the coolant like you do with a counter flow chiller so might not get as good a cold break. Counter chiller works for me because I also use the tubing as a way of moving it from the grainfather into the fermenters
 
I did my first G40 brew a few weeks ago and the temp dropped to 18/19° in a single pass. I had the wort flow on really slow to start but it actually cooled a lot better at around 2/3 open. The water coming out was hot!
CFCs work best if you drop the temperature in a single pass (ie, take the hot wort out of the kettle, through the CFC and then into the fermenter - not back into the kettle).

They also have a time/water-use tradeoff. You can chill the wort faster (up to a point) by turning up the flow on both the wort flow, and your cooling water. But you can chill the wort more efficiently but slower if you slow both down.

A good indication of how efficiently you're chilling the wort (ie, how much/little total cooling water you're going to use) is the temperature output of the cooling water (the red tube). The higher the temperature of this pipe, the less cooling water you'll use overall (if that's a concern to you).

The best way that I have found to 'tune' it, is:
  • Start with the wort valve about half open
  • Adjust your cooling water so that the wort output temperature (via the wortometer) is at your target temperature (for me, 20 degrees)
  • Test the output temperature of cooling water the red pipe.
  • Adjust both cooling water and wort flow as necessary:
    • If the output of the red pipe is 'not hot enough' (and you're concerned about wasting water), turn the flow on both down. The temperature of the cooling water output should go up
    • If you think the output flow of the wort is 'too slow' and you are OK using more water to achieve a faster cool, then turn both up a bit
  • At all stages, maintain the output temperature (wortometer) at your targeted yeast pitch temperature.
 
Use kveik and save water and energy and enjoy a beer quicker! Of course this is a generalisation 😁
 
@NDE79
Using kveik does make a big difference as the wort can cool to 45 very quickly with the counterflow, by the time it has fallen through the air and splashed into the fermenter I find it's below 40 and ready to pitch and oxygenate. Or oxygenate and pitch ( a cause for debate that).
But I don't use kveik for everything.
 
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