wort chiller

[Beertard]

Stuffin around while waiting for the boil I've made myself a pre chiller coil with a couple of ice blocks to reduce the wort chill time, I think it'll work.

 

[gap]

Is the container holding the coil full of water?

 

[Beertard]

The waters flowing from the tap through the coil in the ice bucket then up through the wort chiller coil and out onto the lawn, had to turn it down but its reaching the wort chiller nice and cold.

 

[Beertard]

It's simple but it worked, chilled to 19° with tap water at 23° in 30 minutes.

 

[roller997]

I think the reason that Gap asked the question is that if you don't have water in the container with the ice, you will not transfer the cold temperature to the copper coil as quickly.
Without water in between the ice and the coil, the ice will make contact with the coil, chill it really well for the first few seconds and then melt away and then you just get a bit of radiation cooling which is far less efficient if there is an air gap between the ice and coil than if you had liquid between the ice block and the coil.

Your figures look OK but I get that type of cooling in 30-35 minutes if I stir the wort while it is chilling up until about the last 5 minutes. If I were using a pre-chilling coil in a vessel with ice cubes & water (more surface area with ice cubes than with big ice block) then I would expect lager type temperatures of 10-12 degrees in 30 minutes.
Obviously the cooling temperatures depend on the season and where you are located since the water in Tasmania this time of the year is substantially cooler than the water in Queensland in summer.

I wouldn't use the ice until 10 minutes into it so it gives it a good kick along when most of the heat has already been taken out of the wort.

 

[Beertard]

Yes there was water in with the ice, I could get it down to the tap water temperature in the same time normally but thats never quite cool enough.
Some ice was still there at the end but I'll add it 10 minutes in next time and see how I go.

 

[warra48]

With all due respect, 30 minutes seems a long time to me.

I did a brew today, and chilled it down to under 21ºC in 10 minutes just using my copper coil immersion chiller.

I also have a pre-chiller but no longer use it very often. However, it is useful in summer when the ambient tap water can be quite warm. I agree with Roller997, you are best to use the pre-chiller only for the last 10 minutes or so for best efficiency. If you are taking 30 minutes to chill your wort, try upping the flow through your normal immersion chiller and see if it makes a difference.

 

[Beertard]

I've had it flat out and it still took 30 minutes. What temperature was your tap water though? Last brew my tap water was 25° this time 23°.

 

[warra48]

Yeah, well, I'm a bit further south than you, so obviously my ambient temperature is a little lower than yours.

Getting it down to 19ºC is still a good achievement, no matter how you do it !