All of the Corsair H series all-in-one coolers are sealed loop systems. There isn't anyway for the end user to service the unit without voiding the warranty. These AIO units are typically rated for ~5 years of operation with the contained liquid. I imagine after 5 years the unit will continue to work if the motor doesn't fail and if the radiator/fittings don't corrode. The tubing and fittings used on those units are very very low leakage/evaporation designs.