I have been home brewer for some 3 years now and I'm doing BIAB method. At first I've build myseld a simple immersion chiller which worked fine until I've bumped up the quantity from 25L to 40L (6,6 gallons to 10 gallons). With larger quantity chilling process took more than 1 hour because I had only 7 meters (23 feet) of copper tubing ½ inch or so in diameter. That meant I had a couple of infected batches. So I made myself new counterflow chiller. Dimensions of counterflow chiller were almost the same as immersion chiller so the result was faster than before but not as fast as I wanted. After some taught I've decided to »invent« new type of chiller, immersion counterflow chiller. I've connected the old immersion chiller to counterflow chiller. This works wonders! It chills 10 gallons of wort from 100C to 22C in less than 20 minutes.
As you can see on this pretty lame diagram I've drawn I've just hooked up immersion chiller in front of counterflow chiller. The water from immersion goes directly to T-piece of a copper pipe on the outer side of the counterflow. Inside of counterflow is copper pipe where wort is flowing. The process is practically the same as regular couterflow with the difference that you need to start pumping water for a couple of minutes before you start the pump on the counterflow. This is because water from immersion chiller is still very hot when it enters the counterflow and there would be little or no effect in beginning. In this case I pump first wort back into the cattle until it reaches optimum temperature. When both chillers are working the water leaving counterflow is extremely hot.
I did this combination because I didnt want to buy another chiller instead Ive used existing one so Ive saved some money for other things. When I do a small batch I still use just immersion chiller because counterflow chiller is a bit of a pain to clean properly. Ill add some pictures if someone is interested.
As you can see on this pretty lame diagram I've drawn I've just hooked up immersion chiller in front of counterflow chiller. The water from immersion goes directly to T-piece of a copper pipe on the outer side of the counterflow. Inside of counterflow is copper pipe where wort is flowing. The process is practically the same as regular couterflow with the difference that you need to start pumping water for a couple of minutes before you start the pump on the counterflow. This is because water from immersion chiller is still very hot when it enters the counterflow and there would be little or no effect in beginning. In this case I pump first wort back into the cattle until it reaches optimum temperature. When both chillers are working the water leaving counterflow is extremely hot.
I did this combination because I didnt want to buy another chiller instead Ive used existing one so Ive saved some money for other things. When I do a small batch I still use just immersion chiller because counterflow chiller is a bit of a pain to clean properly. Ill add some pictures if someone is interested.