In a truely 'closed' system, if you have zero pressure at certain temperature and you vary the temperature, you will get expansion and contraction and whenever the system returns to that zero pressure temperature, the pressure will ALWAYS be zero. If in real life it does not adhere to these thermodynamic laws, then you don't have a closed system. There is a leak somewhere.
I am suprised to hear of so many others out there who also have this as normal operation. I'd be curious to hear what the cooling system engineers at work would have to say about this.
Tell me more about this Evans waterless system.
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