Alton | Thermofor Roof Vent Opener Piston Replacement Coconut peat block Superior Ventilation System Equipped with

Superior Ventilation System Equipped with automatic roof vents and optional side louvres for excellent airflow

Its understated and timeless look will compliment your backyard

Decorative roof ridge adds a touch of English sophistication and to deter birds perch on the roof

or small vegetable plants

Alton | Thermofor Roof Vent Opener Piston Replacement Coconut peat block Superior Ventilation System Equipped withThe Thermofor Long Piston Replacement is a direct replacement cylinder designed for Thermofor automatic roof vent openers used in Alton greenhouses. If your current opener is no longer responding properly to temperature changes, replacing the piston is a simple way to restore reliable, automatic ventilation. This heat sensitive cylinder contains a wax core that expands as temperatures rise and contracts as they cool, driving the vent to open and close