Copper vs SS for condenser heat transfer

[shadylane]

I've heard copper conducts heat 25 times better than stainless steel.
Obviously, a copper condenser isn't 25 times better but what is the real life advantage?

[tjsc5f]

I looked at this a bit back when Haggy was working on his heat exchanger calcs.

At low coolant flow rates, say 0.1GPM, copper is about 1.22x better.
At high coolant flow rates, say 5GPM, copper is about 1.55x better.

Those values are pulled from a spreadsheet I have with assumptions I've made and may sound low but the conduction through the pipe wall is only a chunk of the overall heat transfer coefficient.

You can go to Haggy's Shotgun Coil Condenser calculator on the parent sight and play with the materials and flow rates yourself, with your specific condenser dimensions if interested. The results from that calculator aren't exactly the same as mine, but close enough.

[Saltbush Bill]

I suspect wall thickness of tubing will make quite a bit of different as well.

[zach]

The inverse of conductivity is thermal resistance. R = 1/k

The thermal resistance of a heat exchanger wall is usually not the dominant factor in the overall heat transfer rate.

https://www.engineeringtoolbox.com/over ... d_434.html