Immersion chiller - how fast flow

[Chrissyr63]

Hi all,

I made an immersion chiller with 10m of 10mm copper. Use this in 20-26lts of wort. How fast do you run the water through? I have been running it with a trickle of water coming out - this is very hot so assume extracting the heat well but does seem to take ages to get the temp down. Is it just trial error or is there an optimum flow rate ie 1lt a minute?
Am stirring the wort with it also.

Chris

[Andy]

It is indeed a tricky balance! Trial and error I'm afraid. With my CFC then I go fairly slow such that the outlet water is pretty hot but OK to keep my hand under (just).

[barry44]

I put the tap on full

[Andy]

I put the tap on full

That's just a waste of water

[barry44]

Plenty comes from the sky up here!!

[simmyb]

I tend to start with a high flow at the start when you are pulling plenty of heat out of the wort and slow the flow (hey, that rhymes) as the wort temp lowers....

[Fil]

My coil in a coil of 10mm microbore IC required a good 30min of stirring to keep hot beer moving over the coils with a 23-25l brew.. ive read of much better efficiency from complex ic designs with 3 or more non concentric coils but that needs more than basic soldering skills , I went the straight pipe cfc route in SS - chills at a flow rate of 2-3l per min so lets me chill faster and without the arm aching stirring too

[Chrissyr63]

Hi

Simmyb - high at the start makes sense will try this next time

Fil - I do swirl the ic but not continuesly - just every few mins - should I be stirring all the time?
Did a couple of chills today and after 30 mins only down to 35c - still sorting our how to use it.

Chris

[50quidsoundboy]

does anyone understand the actual science behind this? i still remain unimpressed with my immersion chiller but had always assumed faster water = better. is there a reason why throttling back the water would result in quicker chilling?

[mozza]

does anyone understand the actual science behind this? i still remain unimpressed with my immersion chiller but had always assumed faster water = better. is there a reason why throttling back the water would result in quicker chilling?

The greater the temperature difference the higher the efficiency of the chiller so I would guess that the fastest flow rate will chill it the fastest. But if you're on a meter then obviously you should try and save some pennies

[Mr. Dripping]

does anyone understand the actual science behind this? i still remain unimpressed with my immersion chiller but had always assumed faster water = better. is there a reason why throttling back the water would result in quicker chilling?

The greater the temperature difference the higher the efficiency of the chiller so I would guess that the fastest flow rate will chill it the fastest. But if you're on a meter then obviously you should try and save some pennies

That isn't quite right (I think). Yes, the temperature difference will have an effect......but I think you will also need to consider the 'contact time' of the flowing coolant with the hot wort. There must become a point where the coolant is flowing so fast that it doesn't stay in 'contact' with the wort long enough to extract all of the heat it can. Conversely, if it is flowing too slowly, the coolant temperature will rise to a point where it can't pick up anymore heat from the wort before it has made it's whole way around the cooling loop and out the other end.

[mozza]

You're right in that in a given volume the water will carry away less heat from the wort but because the copper is such a good conductor the heat loss from the wort would be greater (probably only marginally) with a fast flow rate. That's my theory anyways

[50quidsoundboy]

You're right in that in a given volume the water will carry away less heat from the wort but because the copper is such a good conductor the heat loss from the wort would be greater (probably only marginally) with a fast flow rate. That's my theory anyways

this is what i reckon as well. the wort is in contact with the coil, not the water after all.