--- product_id: 14106428 title: "Thermofor Double Spring Heavy Duty Automatic Greenhouse Window Opener. Opens Roof Vents and Also Top Hung Side Vents" brand: "elloughton greenhouses" price: "FREE" currency: GBP in_stock: false reviews_count: 2 url: https://www.desertcart.co.uk/products/14106428-thermofor-double-spring-heavy-duty-automatic-greenhouse-window-opener-opens store_origin: GB region: United Kingdom --- # Double spring mechanism Wind-resistant design 2-year guarantee Thermofor Double Spring Heavy Duty Automatic Greenhouse Window Opener. Opens Roof Vents and Also Top Hung Side Vents **Brand:** elloughton greenhouses **Price:** FREE **Availability:** ❌ Out of Stock ## Summary > 🌿 Breathe Easy: Your Greenhouse's Best Friend! ## Quick Answers - **What is this?** Thermofor Double Spring Heavy Duty Automatic Greenhouse Window Opener. Opens Roof Vents and Also Top Hung Side Vents by elloughton greenhouses - **How much does it cost?** FREE with free shipping - **Is it available?** Currently out of stock - **Where can I buy it?** [www.desertcart.co.uk](https://www.desertcart.co.uk/products/14106428-thermofor-double-spring-heavy-duty-automatic-greenhouse-window-opener-opens) ## Best For - elloughton greenhouses enthusiasts ## Why This Product - Trusted elloughton greenhouses brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Wind Warrior:** Engineered to resist wind, ensuring your greenhouse stays secure. - • **Peace of Mind:** Enjoy a 2-year manufacturer's guarantee for worry-free gardening. - • **Effortless Ventilation:** Automatically opens roof and side vents for optimal airflow. - • **Heavy-Duty Performance:** Built to withstand the elements, perfect for any greenhouse environment. - • **Versatile Installation:** Compatible with both roof vents and top-hinged side windows. ## Description This quality greenhouse vent opener automatically opens and closes your greenhouse window as the temperature changes. This model is fitted with a heavy duty double spring mechanism designed for use in exposed locations or on lightweight polycarbonate glazed vents which do not have sufficient weight to prevent the wind opening the vent unintentionally. With the same unique action and smooth twist free operation as the HD3200 this unit incorporating double upper arms has a stronger bracket assembly and includes extra strong springs to provide a very positive closing action. It is recommended for use on both aluminium and timber roof and top hung side vents, particuarly light polycarbonate glazed, in exposed areas to reduce wind snatch effect and provide increased resistance to wind flutter. Finished in a durable polyester powder coating and corrosion resistant throughout. It will lift up to 6 kg (13.25lbs), i.e a vent weighing up to 12 kg (glass area not exceeding 0.65m² in an aluminium frame), with a maximum opening of 35cm (14 inches). PLEASE NOTE: If you have one of the newer type of polycarbonate greenhouses which "trap" the plycarbonate in the frame these will not simply clip on as per the instructions, you will simply need to drill 4mm holes in the vent to bolt through. ## Features - Double spring Greenhouse Automatic Window Opener - Resists wind opening on lightweight vents or in exposed locations - Can also be used on top hinged greenhouse side windows - 2 Year manufacturer's guarantee ## Images ![Thermofor Double Spring Heavy Duty Automatic Greenhouse Window Opener. Opens Roof Vents and Also Top Hung Side Vents - Image 1](https://m.media-amazon.com/images/I/81KRI7pnFrL.jpg) ![Thermofor Double Spring Heavy Duty Automatic Greenhouse Window Opener. Opens Roof Vents and Also Top Hung Side Vents - Image 2](https://m.media-amazon.com/images/I/71PcLL12DRL.jpg) ![Thermofor Double Spring Heavy Duty Automatic Greenhouse Window Opener. Opens Roof Vents and Also Top Hung Side Vents - Image 3](https://m.media-amazon.com/images/I/91uf3RgEa6L.jpg) ![Thermofor Double Spring Heavy Duty Automatic Greenhouse Window Opener. Opens Roof Vents and Also Top Hung Side Vents - Image 4](https://m.media-amazon.com/images/I/810v8I1cUsL.jpg) ## Customer Reviews ### ⭐⭐⭐⭐⭐ Five Stars *by J***L on June 19, 2015* Perfect solution for overheating of greenhouse when you can't do it manually each hour. Works great! ### ⭐⭐⭐⭐⭐ Easy assembly with legible instructions *by E***M on May 2, 2016* Arrived quickly. Easy assembly with legible instructions. Simple installation.Works as advertised with great adjustment control. I used on wooden greenhouse with wood framed top hung windows. --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.co.uk/products/14106428-thermofor-double-spring-heavy-duty-automatic-greenhouse-window-opener-opens](https://www.desertcart.co.uk/products/14106428-thermofor-double-spring-heavy-duty-automatic-greenhouse-window-opener-opens) --- *Product available on Desertcart United Kingdom* *Store origin: GB* *Last updated: 2026-05-30*