"An Evaluation of the ThermoChill Radiators"
Bill Adams - 7/25/03
page 5
Discussion and Conclusions
The ThermoChill radiators are extremely well built, compact and convenient to use due to the built-in shroud, threaded connections and bleed screw. The combination of these features is unique and affords the watercooling enthusiast a range of solutions to fit any cooling need.
No single ‘value’ is proposed as a rating as there is no even nominal consensus within the watercooling community (I hesitate to say ‘Industry’) as to the characterization of testing and rating conditions. My considered opinion would be to use 3.8 lpm (1.0 gpm) as the coolant flow rate and 10°C as the air to coolant temperature differential. (Note that this conflicts with the testing done for this report. Converting to a 10°C basis would double the dissipation values shown in the graphs; the C/Ws are the same.)
Unfortunately this does not in any way resolve the issue: What is to be the air flow for the ‘rating’ conditions?
Despite my reluctance, and conservatism, the radiators ‘need’ a rating. I would suggest the following:
The defined rating conditions are:
- 10°C coolant / air differential
- 3.8 lpm (1.0 gpm) coolant flow rate, and
- a high performance fan (or fans, mounted on one side only).
Under such conditions the radiators would have the following ratings:
Table 1
| Model |
Dissipation |
°C/W |
| HE 80.1 |
100 Watts |
0.104 |
| HE 92.1 |
150 Watts |
0.070 |
| HE 120.1 |
250 Watts |
0.039 |
| HE 120.2 |
400 Watts |
0.024 |
| HE 120.3 |
550 Watts |
0.015 |
Note that the radiators are capable of dissipating more heat than indicated above - the coolant temperature will simply rise until equilibrium is achieved.
A particular difficulty in optimizing radiator performance lies in the area of fan selection. This difficulty is compounded when fan noise is a primary, or significant, concern. Despite the universal existence of fan data sheets, replete with P-Q curves, it is often the case that a specific fan will deliver appreciably better performance than others having similar specs.
The reason for this is not understood by this investigator, but one conclusion is clear: For low noise applications the fan – radiator combination must be tested to assure adequate performance. And if such testing has been done, end users for whom low noise is a primary concern certainly should utilize the specific fan recommended.
Worth remembering: “It is all about air flow, i.e. getting the heat out of the rad. You want to reach the knee of the C/W curve.” **
Many thanks to Karl Smith and more information on the radiators can be found at the ThermoChill website.
**Observation, and more corrections, courtesy of Ralph Nelson.
Bill Adams
