Copper tube refrigerating capacities for pipe evaporators.

[CoolKiwi]

I have a glycol cooler for beer lines. It's had additional taps added over the years. System has a 15.2cc compressor, @-12deg C system has around 800w performance.
Tank temp should be -4C.
The 4.2m of 1/2 tube seems too short. -no load on system. I intend to double what's there, but some idea on ballpark numbers would be helpful.
What I want to calculate is the kw /meter for different tube sizes.
Eg: 3/8 does 50w/mtr at -12 1/2 does 80w/m etc etc.
Can anyone advise on either "quick cheat sheets" or calculations for working this out?

[chemi-cool]

https://www.copper.org/applications/plumbing/cth/

Check it out please.

[CoolKiwi]

Thanks for that link Chemi. Not sure if it has exactly what I'm after, but there is a whole lot of useful info I have not got to yet. Cross sectional areas etc are there.
Links to manufacturers etc and info on evaps with allow fins etc that I will definitely find a use for.
I will update when I find what i'm after.

[CoolKiwi]

Got some rough numbers.
3/8 should be doing between 45w/mtr and 65w/mtr at -10c
1/2 should be hitting around 65w/m to 85w/m at minus 10.
Of course my calcs could be completely wrong.
But the great thing about refrigeration is the ability to give things a go.