My first water cooling loop had a weird leak that only showed up at 3am

Built my first custom loop six months ago and everything was fine for weeks. Then I kept finding a tiny puddle under the reservoir every morning, but it would be bone dry by the time I checked after work. Turns out my noctua fans were thermal cycling at night when the room cooled down, and the slight temperature change was making one fitting loosen up by just a hair. Tightened it with a wrench at 3am while half asleep and it held perfectly ever since. Has anyone else had a leak that only appeared under specific conditions like temp shifts or fan speeds?

2 comments

2 Comments

derek93923d ago

I remember reading a post on a overclocking forum where a guy had a similar problem with his GPU block. It only dripped when his PC was under heavy load and the coolant temp climbed past 45c. Those small temperature swings can mess with the expansion and contraction of the O-rings and fittings way more than people realize. In my experience, the cheap fittings that come with some kits are the worst for this because the threads aren't cut as precisely. Your story about the noctua fans creating a micro climate makes a lot of sense to me, especially since those fans are known for moving air even at super low RPM.

wrenwilson23d ago

The pressure change from coolant heating up can make air pockets shift and cause drips too.