A temperature control system for a controlled environmental vault including an indoor unit and an outdoor unit of a split-type room air conditioner that comprises a mounting component, shroud component, and a shroud cover component. The shroud component and shroud cover component are configured to be installed on the outdoor unit to effectively divert hot exhaust air from the outdoor unit to outside the controlled environmental vault. The mounting component assembles to the indoor unit such that the indoor unit can be secured to an architectural structure such as a ceiling joist or ceiling rafter.