Wort Chiller Just Ain't Chillin

[Burt de Ernie]

Actually while you're experimenting, move the chiller around a bit with moderate flow until the water's coming out almost scalding hot. Then, drop it there and don't move it. Give it a min or 2 until it starts coming out cooler and then agitate the chiller again. It's crazy how much hotter it will come out just by doing that.

With this experiment the discharge temp does matter!

 

[Bribie G]

I could collect it in my black camping shower bag and have a shower. Howdy neighbours.

 

[Goose]

Hi guys

So today was brew day and plumbed up the chiller all good and proper with new fittings from Bunnings.

Tested both theories that have been discussed with much enthusiasm on this thread.

Theory One: Increased/fast water flow will cool faster.

Theory Two: Decreased/slow water flow will cool faster.

Any one want to quickly wage a bet???

Drum roll please.... the winner is Theory Two; slower water flow cooled it faster.

Someone somewhere back on page who knows what suggested agitating the wort chiller every few minutes to assist in speeding up the process. This can also be confirmed and made a HUGE difference.

So there it is guys, thanks everyone for your input and I guess regardless of your theory or argument the results speak for themselves.

Thanks everyone for your input -until the next argument (ahem debate) chat soon and thanks for your time.

Ollie

Howdy Ollie. Thanks for posting this.

As said, there are many variables involved. As homebrewers, the ones in our control are the temperature of the cooling water inlet, its flowrate, and also the one you have identified which is the flowrate of the wort across the surface where we are trying transfer the heat. In the case of an immersion chiller, that would mean how fast the wort is circulated around the immersion chiller coils, and in the case of a plate chiller how fast it allowed to pass through the exchanger.

It would be a challenge to make an accurate conclusion as to the effect of cooling water flowrate on rate of heat removal from the wort unless you can keep all the other variables constant. That would probably best be tested by two consecutive cooling runs where you measure the temperature of the wort as a function of time for a fixed cooling water flowrate. I am assuming your cooling water starts at ambient and there will not be much variation in that, and that however you agitate the wort is the same for each run you do. Every other variable should be the same as well, including where you measure the temperature of the wort.

It is meaningless to make a judgement on the rate of heat removal based on the cooling water exit temperature if you are also changing the wort flowrate by random agitation, and changing the cooling water flowrate during the run.

Would be great if you could re-run the experiment as described above and let us know the result. You don't need to do it on wort either, just use water in place of wort for the purposes of the experiment.

 

[Ollieb]

Howdy Ollie. Thanks for posting this.

....

Would be great if you could re-run the experiment as described above and let us know the result. You don't need to do it on wort either, just use water in place of wort for the purposes of the experiment.

Hey Goose
Next time the burner is firing up will def not be for only water! ... I will be sure to give it another test and let you guys know any more details I get but it will not be for a few weeks as I am heading away.
Cheers

 

[Ducatiboy stu]

Did you constantly agitate or move the wort.

Its really going to be meaningless if you didnt.

What you need is a way of agitating it at a constant rate...some sort of mixer paddle in the middle of the coil with a fixed speed. That way you know the wort is agitating at the same constant speed for both tests.

 

[Parks]

It was already meaningless as he judged based on the temperature of the outlet water.


Sent from my iPhone using Tapatalk

 

[Ducatiboy stu]

True

 

[Bribie G]

Just jumping on here to ask something I posted a few days ago but no response, and I don't think it's worth raising a thread:

Do pond pumps of the sort sold by Bunnings or Masters use normal garden hose or do you have to get a special hose for I/O ?

 

[wide eyed and legless]

The temperature of the outlet water can be monitored as long as the temperature of the wort is being monitored at the same time and the outlet temperature has to be lower than that of the wort otherwise the heat from the outlet will be heating the temperature of the wort.
Bribie I have a pond pump and it does take a garden hose.

 

[Bribie G]

Cheers, I'll hit up Masters tomorrow.

 

[danestead]

The temperature of the outlet water can be monitored as long as the temperature of the wort is being monitored at the same time and the outlet temperature has to be lower than that of the wort otherwise the heat from the outlet will be heating the temperature of the wort.
Bribie I have a pond pump and it does take a garden hose.

In reference to this, if it was a counterflow copper coil chiller or counterflow plate chiller, I'm thinking it would be possible to have hotter water coming out of the outlet of the chilling water, than the outlet of your wort going into the fermenter. I haven't tested this, however Im thinking it's possible.

Thoughts?

 

[Goose]

What you need is a way of agitating it at a constant rate...some sort of mixer paddle in the middle of the coil with a fixed speed. That way you know the wort is agitating at the same constant speed for both tests.

The best way that I have seen is in the Cheeky Peak 3V setup. Check out the lower pump and the inlet/outlet to the boiler. That's a whirlpool system which is operated as you cool, to keep the wort circulating in the HLT which also serves the purpose of coning the trub in the centre prior to rundown to the fermenter. Great idea IMHO.

 

[Bribie G]

In reference to this, if it was a counterflow copper coil chiller or counterflow plate chiller, I'm thinking it would be possible to have hotter water coming out of the outlet of the chilling water, than the outlet of your wort going into the fermenter. I haven't tested this, however Im thinking it's possible.

Thoughts?

That makes my brain hurt.

 

[Parks]

In reference to this, if it was a counterflow copper coil chiller or counterflow plate chiller, I'm thinking it would be possible to have hotter water coming out of the outlet of the chilling water, than the outlet of your wort going into the fermenter. I haven't tested this, however Im thinking it's possible.

Thoughts?

No.

Yeah, I re-read it and decoded the cypher and I agree with below it should be OK but not sure what the point is.

 

[Goose]

In reference to this, if it was a counterflow copper coil chiller or counterflow plate chiller, I'm thinking it would be possible to have hotter water coming out of the outlet of the chilling water, than the outlet of your wort going into the fermenter. I haven't tested this, however Im thinking it's possible.

Thoughts?

of course. but what is not possible is to have the wort exit temperature be lower than the cooling water inlet temperature.

(That is if I read your hypothesis correctly, and I am referring to a plate chiller)

 

[Ducatiboy stu]

Or the wort inlet temp lower than your chiller out temp.

 

[danestead]

Ive even confused myself here. I cant even figure out how to put what i was meant to be getting at into words haha

 

[danestead]

Ok, I think i have sussed out what was going on in my brain a few minutes ago. I was mistakenly thinking he was saying that your cooling water outlet must be cooler than the 'outlet of the wort' ie into the fermenter. On rereading he was actually saying it must be cooler that the wort still in your kettle, which makes sense now.

Anyway, back to my counterflow chiller theory, if you had 100 degree wort and 20 degree tap water and you ran them at the same flow rate, you would expect the temperature to equal out in the middle ie 60 degrees, however because I was talking about a counterflow chiller, you will do better than halfway ie 50 degrees or whatever.

If you flow your tap water faster than the wort though, you'd expect the wort to chill down to much lower than 50 degrees though.

Ok. Ill just shut up now and go back to my box

Edited: added some stuff and rephrased

 

[Ducatiboy stu]

Um....er...no...would depend on your volumes, surface areas, length etc

You would get a different result if you used different sized tube.

The longer/bigger you counter flow chiller the more heat you can transferr

 

[Parks]

Your wort should be 20 degrees coming out of the chiller in this case. You need to have the wort flow slow enough and the water flow fast enough to achieve it.