--- product_id: 309742723 title: "E100 Solar Thermal Heat Transfer Fluid 5L" price: "£63.55" currency: GBP in_stock: true reviews_count: 4 url: https://www.desertcart.co.uk/products/309742723-e100-solar-thermal-heat-transfer-fluid-5l store_origin: GB region: United Kingdom --- # Pre-mixed, no dilution needed Protects down to -20°C Includes biocide for system longevity E100 Solar Thermal Heat Transfer Fluid 5L **Price:** £63.55 **Availability:** ✅ In Stock ## Summary > ❄️ Stay chill, stay efficient—solar protection that’s always a step ahead! ## Quick Answers - **What is this?** E100 Solar Thermal Heat Transfer Fluid 5L - **How much does it cost?** £63.55 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.co.uk](https://www.desertcart.co.uk/products/309742723-e100-solar-thermal-heat-transfer-fluid-5l) ## Best For - Customers looking for quality international products ## Why This Product - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Ready-to-Use Formula:** Pre-mixed blend means zero hassle—just add directly for instant protection. - • **Freeze-Proof Confidence:** Engineered to shield your solar system down to -20°C, ensuring year-round reliability. - • **Built-In Biocide Defense:** Protects your system from microbial growth, extending lifespan and efficiency. - • **Precision Protection Check:** Use a refractor to verify optimal freeze protection—because details matter. - • **System Cleanse Compatibility:** Works best when paired with C300 flush, following BS7593:2006 standards for peak performance. ## Overview E100 Solar Thermal Heat Transfer Fluid is a 5L pre-mixed solution designed to protect solar heating systems from freezing down to -20°C. It combines mono ethylene glycol, inhibitors, and biocide to ensure system longevity and microbial defense. Easy to use with no dilution required, it supports system maintenance protocols for optimal performance. ## Description E100 Solar Thermal Heating Fluid 25L Pre Mixed to treat 25L System to minus 20 degrees E100 Solar Thermal Heating System Fluid is a blend of Mono Ethylene Glycol, Inhibitor and Biocide Blended for protection of down to minus 20 degrees C Simple add E100 to your system without any dilution in order to receive the full minus 20 degree protection Use a refractor in order to double check the protection No need to add any other products to your Solar System Water Safety data sheets available upon request Review: E100 Solar Thermal Heat Transfer Fluid 5L - Excellent service...just what I wanted Review: Perfect for my requirements. - Used for topping up solar water heating circuits. ## Features - No need to add any other products to your Solar System Water - add E100 to your system without any dilution in order to receive the full minus 20 degree protection - Use a refractor in order to double check the protection - Product includes biocide - For best results systems should first be cleansed and then flushed with C300 in accordance with BS7593:2006 ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B08KY2H6RT | | Batteries Required? | No | | Batteries included? | No | | Customer Reviews | 4.5 4.5 out of 5 stars (29) | | Date First Available | 5 Oct. 2015 | | Item Package Quantity | 1 | | Item Weight | 5 kg | | Manufacturer | Trade Chemicals | | Manufacturer reference | C100S25 | | Part Number | C100S25 | | Size | 5L | ## Images ![E100 Solar Thermal Heat Transfer Fluid 5L - Image 1](https://m.media-amazon.com/images/I/61SpvG0ANGL.jpg) ![E100 Solar Thermal Heat Transfer Fluid 5L - Image 2](https://m.media-amazon.com/images/I/61t7CNm4wxL.jpg) ![E100 Solar Thermal Heat Transfer Fluid 5L - Image 3](https://m.media-amazon.com/images/I/41+kppVs2iL.jpg) ## Questions & Answers **Q: Will this mix with other transfer liquids ?** A: I would get in touch with the manufacturer and ask them first, I know some solar thermal heat transfer products are incompatible. I think the E100 is mono ethylene glycol MEG but check first! **Q: Can we use this in electric radiators?** A: No. This product is for solar panels not for electric heaters. **Q: Can this be used with a wet underfloor heating system?** A: No, this is for solar heating system, underfloor heating is the same as radiators - water with inhibitor **Q: Can you recommend a compatible pump to use with this solution?** A: you need a magnetic drive 12 or 24 volt solar pump if you are using it for solar. Either way a magnetic drive pump is what you need for chemicals. ## Customer Reviews ### ⭐⭐⭐⭐⭐ E100 Solar Thermal Heat Transfer Fluid 5L *by T***R on 2 January 2023* Excellent service...just what I wanted ### ⭐⭐⭐⭐⭐ Perfect for my requirements. *by A***R on 8 November 2022* Used for topping up solar water heating circuits. ### ⭐⭐⭐⭐⭐ A really good product and a good price *by T***L on 7 May 2022* Used in my solar hot water system very good product . ## Frequently Bought Together - E100 Solar Thermal Heat Transfer Fluid 5L - Dyna-Living Test Pump for Water Pipe Line Installation - Heating System Water Leakage Pressure Tester (Yellow) --- ## 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/309742723-e100-solar-thermal-heat-transfer-fluid-5l](https://www.desertcart.co.uk/products/309742723-e100-solar-thermal-heat-transfer-fluid-5l) --- *Product available on Desertcart United Kingdom* *Store origin: GB* *Last updated: 2026-05-15*