Sounds like a fun project. Send me the airflow curves and the key parameters you’re balancing—temperature rise, pressure drop, fluid choice, and any safety margins you’ve set. I’ll sift through the numbers, spot any inconsistencies, and suggest tightening the tolerances where you can keep the loop efficient without sacrificing reliability. Just hit me with the specs and we’ll get the loop humming in no time.

Your numbers line up mostly, but a few things deserve a second look. The inlet is already at 90 °C, and you’re adding a 30 °C rise, so the hot spot hits 120 °C. That’s a lot for a 30 % ethylene‑glycol mix—its viscosity climbs fast, and you’ll be pushing the boiling point of the mixture down a bit. If you’re targeting a 50 °C operating point, the inlet temp should be closer to that, or you’ll need to re‑evaluate the mixture ratio. The flow rate you’re asking for—0.2 L/s, which is about 28 CFM— is far below the fan’s 200 CFM at 1.2 bar. That means the fan is over‑specified; you’ll have a very low pressure drop and a lot of wasted energy. Either cut the fan size or raise the desired pressure drop. The safety margins look reasonable: 15 % on 1.2 bar gives a maximum of about 1.38 bar, and 10 % on a 30 °C rise gives a ceiling of 33 °C. Just make sure the heat exchanger and the fluid can comfortably handle the 120 °C hotspot without cracking. Tightening the inlet temperature and adjusting the fluid concentration should bring the loop into a cleaner, more efficient regime.

Sounds solid. Keep an eye on the thermal gradients after you swap the curves—sometimes the 20 % glycol still feels a bit thick when it hits 120 °C. Let me know how the new fan spec plays out on the noise budget too. Happy to review once you send the updated sketch. Good luck!