Thermo Box - Insulated Plenum Boxes for Linear Slot Diffusers
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About Thermo Boxes
Ventmann Thermo Boxes are high-performance insulated plenum boxes engineered to enhance airflow efficiency while reducing heat loss and condensation within HVAC systems. Supplied in a flat-pack format, they optimise transportation, simplify on-site storage, and streamline installation workflows for contractors.
Installation is fast and reliable, with the box folded into position and secured using the included fixings and a standard SQ2 driver. Pre-drilled fixing points ensure accurate alignment, consistent build quality, and reduced installation time.
To support flexible ductwork layouts, each Thermo Box includes factory pre-scored knock-outs for 125mm, 160mm, and 200mm duct connections. External spigots (by others) are mounted using suitable self-drilling screws and sealing methods to create a secure, airtight connection.
Offered in three standard lengths to match Ventmann linear slot diffusers, and three width codes (A, B, and C), Ventmann Thermo Boxes provide precise system compatibility and dependable thermal performance for residential, commercial, and high-end architectural HVAC applications.

