Inexplicable consumption

Hello,
I'm fighting 6 months ago with the consumption of refrigerating liquid from my Diesel spazio.

I do about 10 km and the level of the liquid lowers me a lot in the container
since then I changed all the snack hoses, the thermostat and the heating tap.
It is not observed with the naked eye lost in the engine radiator or in the heating,

it is also not seen that there is water in the engine oil

when complete refrigerant liquid I always do it to the mark that is in the middle of the container and when I take the cover from it with the hot engine a "shhhh" is heard as if there was pressure inside the container (I do not know if this is correct).

The liquid circulates well inside it

if I leave the car stopped 2 or 3 days the liquid does not fall so that the problem appears when

the temperature is never passed the 90 degrees and the fan is well

at first glance there is no loss noly loss anywhere or even with the hot engine

no longer know what to do. If someone can throw me a clue to solve this I appreciate it
greetings
Marquin

Control the temperature sensor that is working well, check if the canister valve is not locked open and take fuel pressure to see if the regulator is fine.