--- title: 3D Printed Einstein-Szilard Refrigerator Cools With Fire description: Ben Krasnow built a transparent, 3D printed Einstein-Szilard absorption refrigerator powered by an open flame. Unlike typical ammonia-water absorption fridges,... canonical: https://daily.dev/posts/3d-printed-einstein-szilard-refrigerator-cools-with-fire-no76vbmrc twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: 3D Printed Einstein-Szilard Refrigerator Cools With Fire | daily.dev og:description: Ben Krasnow built a transparent, 3D printed Einstein-Szilard absorption refrigerator powered by an open flame. Unlike typical ammonia-water absorption fridges,... og:url: https://daily.dev/posts/3d-printed-einstein-szilard-refrigerator-cools-with-fire-no76vbmrc og:image: https://api.daily.dev/og/posts/no76VbMRc.png og:image:alt: 3D Printed Einstein-Szilard Refrigerator Cools With Fire og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # 3D Printed Einstein-Szilard Refrigerator Cools With Fire **[Hackaday](https://daily.dev/sources/hackaday)** · 2 min read · 0 upvotes · 0 comments ## Summary Ben Krasnow built a transparent, 3D printed Einstein-Szilard absorption refrigerator powered by an open flame. Unlike typical ammonia-water absorption fridges, this design uses a third refrigerant liquid, here nonflammable perfluoropentane instead of the usual butane, since the system runs on fire. The body is clear resin with a copper block carrying heat from the flame into the boiler, though ammonia solution dissolves copper so it is not a long-term fix. A single internal fluid path makes it prone to airlocking from stray bubbles, but Krasnow got it to cool five degrees Celsius below ambient. He notes you could cool a drink with sufficiently high-concentration alcohol by burning a portion of it. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What is an Einstein-Szilard refrigerator and how is it different from a normal ammonia absorption fridge? It's an absorption refrigerator design that uses a third liquid as refrigerant instead of relying solely on ammonia and water. A strong ammonia-water solution is boiled apart, and the ammonia gas lowers the partial pressure to make the refrigerant evaporate; the gases later mix with water so the refrigerant condenses and the cycle repeats, avoiding the high pressures normal ammonia-water systems need. _Tinkerers comparing refrigeration cycle designs can keep exploring builds like this through daily.dev._ ### What refrigerant did Ben Krasnow use in his 3D printed flame-powered absorption fridge instead of butane? He used nonflammable perfluoropentane instead of the usual butane, because the system was being heated with an open flame and butane would have been a fire risk. The refrigerator body was 3D printed in clear resin with a copper block conducting heat from the flame into the boiler chamber. _Builders picking safe materials for heat-driven projects can track similar write-ups on daily.dev._ ### How much cooling can a DIY Einstein-Szilard absorption refrigerator achieve? A 3D printed, flame-heated version reached about five degrees Celsius below ambient temperature. The single internal fluid path made it prone to airlocking from stray bubbles since almost no pressure differential exists between sections, which limited how reliably it ran. _Anyone benchmarking DIY cooling builds can follow more experiments like this on daily.dev._ ## Similar posts on daily.dev - [Off-Grid Refrigeration Using Fire And Salt](https://daily.dev/posts/off-grid-refrigeration-using-fire-and-salt-gst4zwaje) · Hackaday · 0 upvotes · 0 comments - [Solid-State Elastocaloric Cooling Hits Sub-Zero Mark](https://daily.dev/posts/solid-state-elastocaloric-cooling-hits-sub-zero-mark-c8fmv3ivg) · IEEE Spectrum · 0 upvotes · 0 comments - [3D Printed Cubes Provide Passive Cooling](https://daily.dev/posts/3d-printed-cubes-provide-passive-cooling-ombyjp4em) · Hackaday · 0 upvotes · 0 comments - [Barocal can cool your food and drink by squeezing a hunk of plastic crystals](https://daily.dev/posts/barocal-can-cool-your-food-and-drink-by-squeezing-a-hunk-of-plastic-crystals-u1anhv4xd) · TechCrunch · 0 upvotes · 0 comments --- Tags: [#hardware](https://daily.dev/tags/hardware) [View this post on daily.dev](https://daily.dev/posts/3d-printed-einstein-szilard-refrigerator-cools-with-fire-no76vbmrc) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"3D Printed Einstein-Szilard Refrigerator Cools With Fire","url":"https://daily.dev/posts/3d-printed-einstein-szilard-refrigerator-cools-with-fire-no76vbmrc","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/3d-printed-einstein-szilard-refrigerator-cools-with-fire-no76vbmrc"},"datePublished":"2026-10-31T08:13:50.217Z","dateModified":"2026-10-31T08:14:22.368Z","description":"Ben Krasnow built a transparent, 3D printed Einstein-Szilard absorption refrigerator powered by an open flame. 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