water chiller question

[chillman]

I have a question about water chillers.
I want to build up a 7Kw water chiller.
I am building a small water tank with glycol, the glycol will be cooled by a brazed plate heat exchanger using refrigerant as the primary cooling.
In that tank I want to run a length of 3/8" copper pipe in that tank to cool down water running to another application.
Does anyone have information on how to work out the total length of pipe i will need

[frank]

You are going to have to provide a lot more information before any calculations can be done, such as:

What are the expected cooling water entering and leaving temps (T1, T2)

How big is the load you are cooling

What temp is the refrigerant evaporating at

How much water is in the tank

What concentration is the glycol

What will the primary circuit flow rate be in kg/s

What will the secondary flow rate be in kg/s

etc

[Brian_UK]

If you are into a bit of calculation then you could start here...

http://en.wikipedia.org/wiki/Heat_transfer_coefficient

also
http://www.eng-tips.com/viewthread.cfm?qid=171100&page=1