The main goal of this project was to increase the reliability of CRYSIS by separating the ionization region from the insulating volume which contains vacuum seals at the cryostat. These volumes are separated with two bellow units installed between the cryostat and both ends of the vacuum vessel. The bellow units contain drift tubes with different fixed temperatures, heat shields, feedthroughs for drift tubes, and a gas delivery tube for gas injection. Preliminary results of tests after CRYSIS vacuum separation are presented.