[SOLVED] Refilling a CLC - How much space to leave?

[pmjm]

All the guides for refilling CLC's say you need to get all the bubbles out. But how much do I need to account for coolant expansion at high temps? How much free space do I need to leave in the loop to allow for that expansion? Or do I just yolo it and fill it up to the brim?

Thanks in advance!

 

[USAFRet]

guides for refilling CLC

??

Generally, you don't refill those.
Closed for a reason.

What do these "guides" say about empty space?

 

[pmjm]

I am draining, cleaning and refilling the troubled Enermax LiqTech TR4 cooler, these are known to have significant galvanic corrosion after a few months due to insufficient anti-corrosives in the fluid. Unfortunately there is no better CLC for Threadripper as nobody else's block covers the whole IHS.

As for the guides I've read/watched, either they make no mention of empty space or they say something obscure like "leave a little bit of room for coolant expansion under heat" but ambiguous terms like that are useless.

 

[jappy]

You can calculate that volume. Here's a link: https://www.engineeringtoolbox.com/volumetric-temperature-expansion-d_315.html

 

[tennis2]

I'm no water cooling expert, but I'd fill it full as possible. TBH, unless you fill it and seal it with the whole thing submerged in a tub of fluid from start to finish, you're bound to have SOME air left inside.

 

[jappy]

I'm no water cooling expert, but I'd fill it full as possible. TBH, unless you fill it and seal it with the whole thing submerged in a tub of fluid from start to finish, you're bound to have SOME air left inside.

Nor am I but when I did my first custom loop about 12 years ago, I didn't account for thermal expansion. I kept filling the reservoir as air bled itself from the system over a couple of days. Satisfied with my thick headed efforts, I sealed the system and therein made a critical error. Fluids don't compress an appreciable amount and the force they exert is an awesome thing. It will leak if enough thermal expansion occurs and it has no place else to go.

 

[pmjm]

You can calculate that volume. Here's a link: https://www.engineeringtoolbox.com/volumetric-temperature-expansion-d_315.html

Thank you! Based on this calculation and some rough estimates on my part, looks like I need to account for 4-5% expansion, which means around 14 mL in a 300mL 360mm cooler.