The first zero fan radiator idea I had was complex and difficult to construct, so it is on hold right now.
Now I made this new radiator type 2 made of two 1.7 meter long copper tubes, 37mm diameter outside.
The waterhose connectors are homemade, 14mm outside, 10mm hole, 12mm drill hole in copper plate.
The water fillig point will be the highest point in this system, to let air get out.
To let air out, the hose connector is mountet at the verry top of the tube.
After soldering the end plates was cut round to fit the 37mm tube
After a few minutes of work
I cleened the tubes on the outside with sandpaper to make painting result better,
the inside was also cleened, using a wire and a wet cloth :-)
When I was done they was painted blavk mate, to improve cooling performance.
They have a total outside area of 0.4m2
Here the two copper tubes was mountes under the desk, so it is not in the way at all.
The copper radiator setup ended up with a water temperature = 31C
After a few days I come up with a simple and cheap way to improve performance !
Why not add 11 meter ½" black garden hose to the system, and place it close the the cold walls.
See the hose is not in the way, nobody will fall over it.
All walls are a bit colder compared to room temperature, also in the summer time.
Now my water temperature dropped to 25C
I will try to find some cable clips that fits this big hose, so I can mount them 10cm away from each other.
Also I want improve the heat transfer contact with the cold walls.
Several different colours and types exist, I wanted black due to the better heat radiation this colour has.
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