Post Rad Chiller Concept

[Martinm210]

It's sad, but I woke up this morning thinking about this and realized I'm wrong in how I was thinking about this.

While it does take 395 watts to change a 1.5 gpm water delta 1 degree, that's assuming there is no radiator at work. As if you had nothing in the system pumping water at 1.5gpm that was automatically getting reheated the exact same amount it's getting cooled, that's not what we have here.

To figure out the result, you'd have to figure out the heat being dumped in and the radiator in use.

If the heat going in from blocks and pumps is say 200 watts, and without the chiller the water to ambient temperature was 8 degrees. Even only removing 100 watts of that with a chiller should be good for almost a 4 degree improvement.

So if you only had 200 watts dumping in and used 395 watts for removal, you'd be below ambient with your coolant temperature and over 8 degrees cooler, not 1 degree.

A chiller with a radiator like this should be an easy way to get coolant temperatures down to ambient and a little lower. Since it's going to be hard to get below that because of the radiator, it would be an easy and safe way to avoid any of the typical TEC problems with condensation The 395 watts per degree doesn't really apply unless you matched that heat going in...eventually below ambient, the radiator would match that when it reached an equillibrium. The radiator inline on the coolant side will slowly start working against the effort as you dip below ambient. You could also figure that out just like radiator cooling. If you had an excess of 200watts going into the chiller than being dumped. a PA120.2 would dump that amount back in once you got down to about 10C below ambient.

You should see improvements in temperature even with smaller TECs where the radiator is still helping.
That's why my numbers weren't clicking for me, I wasn't thinking about the radiator.

But one example would be like this
250 watts in
PA 120.2 with nexus fans at 12V
This is probably off a little because of the curves used(based on 10C delta), but the normal water delta would be 12C without the chiller

If you put 3 62watt TEC in line, assuming 80% efficiency, you'd remove about 150 watts of heat.
In the end your net heat in is only about 100 watts, which would give you coolant temps that are only about 5C higher than ambient (7 degree improvement)

And that's all under full load, on idle you'd probably have less than the 150 watts being removed by the TECs, so you'd probably have coolant temps near or lower than ambient.

I think it's a neat idea, and a low risk/maintenance one too. No condensation to worry about because you'll never get block temps below the dew point, yet it will do a really nice job of getting coolant temps near or to ambient. You'd basically have all the same conveniences and easy installation of a regular water cooling setup, but along with an extra bump in TEC performance.

I'm changing my mind, I'd probably start with smaller TEC's, if you go too big, you'll probably get way down below ambient and may get into dew point/condensation territory.