Showing results for 
Search instead for 
Did you mean: 

Water cooling question

Level 10
Im running 3x Monsta 480's with NB Eloop pwm fans along with 2x mpc 655 pumps and bitspower d5 dual pumptop and 250ml res. I have my loop set up to fill the res and im not sure if i should cap the top or not.

reason being is that when the system turns on the pumps suck the water down about an inch and during heavy gameplay the water rises back up about a half inch. I tried capping it off about a month ago and i believe it caused my flow indicator from bitspower to crack and leak:(

I have the air bled out and now wondering if my coolant is just evaporating with it being open at the top or not?

i know water expands while heated but should i not worry about it and just seal the top? Also would i cap it while the pumps are on or have the system off first?

thanks for any help.

Level 40
Funny...we had this discussion here the other day too....I leave the cap on but not screwed down fully so the res can "breathe"....same reason...dual D5s starting up drop the water level in the res and then expansion/contraction of rads and loop etc.

I don't care about evaporation since I run only water in my loop and change it every 8 weeks....

If you do cap it...cap it warm...negative pressure better than positive I would say....

Level 10
Thanks Arne, ill do just that and cap it while its warm~!

Level 14
list the parts you are cooling by water.
if the water drops that mutch i would guess the pumps are going on full speed and expanding the tubes becouse of restriction in the loop.

Level 16
Depending on how your reservoir is attached to the loop, that decrease on the level of the coolant may be good... - if the res is completely sealed, a vacuum will form in it, which will help keeping the air bubbles out of the system...

That drop in the coolant level most likely happens because of the expansion of the tubing... I haven't seen it with rigid tubing...

If your fittings are good, tubing is good, then I would not worry about it even if you completely seal the reservoir...