{"product_id":"castair-all-filters-bowl-float-drain-valve-afd1","title":"Castair, All Filters, Bowl Float Drain Valve AFD1","description":"\u003cp\u003eThe \u003cstrong\u003eCast Air AFD1\u003c\/strong\u003e is a float-operated automatic drain valve for compressed air filter bowls, priced at $77.77. It fits all Castair filter bowls via a 1\/8\" NPT connection. If you are running Castair inline filters — at individual shop drops, at the main line, or in a spray booth — and those filter bowls are collecting water that requires manual draining, the AFD1 makes the draining automatic. No timers, no solenoids, no electrical work. A mechanical float inside the bowl rises with the water level and opens the drain when the condensate reaches a threshold, then closes when the bowl is clear.\u003c\/p\u003e\n\n\u003cp\u003eFilter bowls exist to pull moisture and particulates out of the air stream before the air reaches tools, paint guns, and pneumatic equipment. But a filter bowl is only useful if the condensate it collects actually gets removed. A bowl that overfills passes moisture downstream just like no filter at all. Manual bowl draining is one of those maintenance tasks that is easy to perform when someone remembers, and easy to skip when a shop is busy. The AFD1 removes the human element entirely.\u003c\/p\u003e\n\n\u003ch2\u003eHow a Float Drain Works\u003c\/h2\u003e\n\u003cp\u003eInside the AFD1 is a mechanical float — the same basic principle used in a toilet tank or a carburetor float bowl. As condensate collects at the bottom of the filter bowl, the float rises with the water level. When water reaches the drain threshold, the float mechanism opens a drain port and evacuates the condensate. When the bowl is drained, the float drops and the drain port closes. The cycle repeats automatically every time condensate accumulates. No electricity. No programming. No adjustments.\u003c\/p\u003e\n\n\u003cp\u003eThis passive mechanical approach is what makes float drains suitable for locations where running power to the filter is impractical — which describes most inline filter installations. The AFD1 threads directly into the bowl's existing drain port and replaces whatever manual drain fitting was there before.\u003c\/p\u003e\n\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFloat-Operated Automatic Drainage:\u003c\/strong\u003e Mechanical float actuates drain port automatically — no timers, solenoids, or electricity required\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003e1\/8\" NPT Connection:\u003c\/strong\u003e Threads into the standard drain port on all Castair filter bowls\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eUniversal Castair Bowl Fitment:\u003c\/strong\u003e Fits all Castair filter bowl sizes in the AFD series\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePassive Mechanical Operation:\u003c\/strong\u003e No consumable electronic components, no power supply, no timer battery\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eContinuous Protection:\u003c\/strong\u003e Drains as condensate accumulates, not on a fixed schedule — matches actual moisture load\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePrevents Bowl Overflow:\u003c\/strong\u003e Keeps filter bowls operating within capacity so they actually filter instead of passing water\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSimple Installation:\u003c\/strong\u003e Thread-in replacement for existing manual drain fitting on compatible filter bowls\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCast Air Quality:\u003c\/strong\u003e Built to the same manufacturing standard as the Castair compressor and filter product line\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhy Filter Bowl Draining Matters\u003c\/h2\u003e\n\u003cp\u003eAn inline compressed air filter does two things: it removes particulates and it separates condensate. The condensate collects in the bowl at the bottom of the filter housing. In a high-humidity environment or on a compressor that runs hard, a filter bowl can fill up in hours. When it fills, moisture carries over into the downstream air stream. At a spray gun, that means fisheye, blushing, and adhesion failures. At an air tool, it means accelerated internal corrosion and shortened tool life. At a pneumatic control, it means stuck valves and erratic operation.\u003c\/p\u003e\n\u003cp\u003eThe AFD1 keeps the bowl drained so the filter keeps doing its job. This is especially important at high-volume stations — main line filters, booth supply filters, and any point-of-use filter that sees significant airflow during peak hours.\u003c\/p\u003e\n\n\u003ch2\u003eWhat's in the Box\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e1x Cast Air AFD1 bowl float drain valve\u003c\/li\u003e\n  \u003cli\u003e1\/8\" NPT thread fitting for standard Castair filter bowl drain ports\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eAvailable Configurations\u003c\/h2\u003e\n\u003cp\u003eCast Air offers two float drain valve options for filter bowls. The correct one depends on your filter bowl series:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eAFD1 — $77.77 (this part):\u003c\/strong\u003e Watts Bowl float drain. 1\/8\" NPT connection. Fits all Castair filter bowls. Use this if you have standard Castair inline filters.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eAFD3 — $47.74:\u003c\/strong\u003e THB Bowl float drain. 1\/4\" NPT connection. Fits Castair THB-series filter bowls specifically. Lower cost, different bowl series. If you have THB bowls, use the AFD3.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eFor automatic tank draining (the receiver tank itself, not the filter bowl), see the ADVS ($119.43) or ADVSM ($154.00) air-operated tank drain valves.\u003c\/p\u003e\n\n\u003ch2\u003eWhen Does a Shop Need the AFD1\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eChoose the AFD1 when:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eYou have Castair inline filter bowls that currently require manual draining\u003c\/li\u003e\n  \u003cli\u003eYour filter bowls are in a humid environment and accumulate condensate quickly\u003c\/li\u003e\n  \u003cli\u003eYou want automatic bowl draining without any electrical work at the filter location\u003c\/li\u003e\n  \u003cli\u003eYou are upgrading from manual drain petcocks on existing Castair filter bowls\u003c\/li\u003e\n  \u003cli\u003eYou are installing new Castair filters and want automatic drainage from the start\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eChoose the AFD3 instead when:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eYour filter bowls are the THB series — the AFD3 is the correct fit for THB bowls and is $30 less\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eNote on tank draining:\u003c\/strong\u003e The AFD1 and AFD3 are filter bowl drains only. They do not mount on or drain the receiver tank. For tank drain automation, use the ADVS or ADVSM air-operated tank drain valves.\u003c\/p\u003e\n\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePart Number:\u003c\/strong\u003e AFD1\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManufacturer:\u003c\/strong\u003e Cast Air (Castair), Minnesota\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eType:\u003c\/strong\u003e Bowl float drain valve — automatic, mechanical\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eConnection Size:\u003c\/strong\u003e 1\/8\" NPT\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCompatible Bowl Series:\u003c\/strong\u003e All Castair filter bowls (Watts Bowl series)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eOperation:\u003c\/strong\u003e Mechanical float — no electricity required\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDrain Trigger:\u003c\/strong\u003e Float-activated when condensate reaches threshold level\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePrice:\u003c\/strong\u003e $77.77\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCountry of Origin:\u003c\/strong\u003e USA (Minnesota)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhy Buy From Air Compressor Factory Direct?\u003c\/h2\u003e\n\u003cp\u003eAir Compressor Factory Direct has stocked Cast Air compressors and accessories since 2016. We carry the full Castair filter and drain accessory line, so you can get both the filter and the correct drain valve from a single source. If you are not sure whether your bowl series takes the AFD1 or the AFD3, call us — give us the filter part number and we will tell you exactly which drain fits.\u003c\/p\u003e\n\u003cp\u003eEvery order ships free. Full manufacturer warranty. Our tech support is staffed by people who work with compressed air systems daily, not a general call center. We stock these parts because shops need them, and we will get you the right one the first time.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCall 866-217-0063 for quick answers and help!\u003c\/strong\u003e\u003c\/p\u003e","brand":"Cast Air","offers":[{"title":"Default Title","offer_id":53342513430741,"sku":"AFD1","price":143.42,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0622\/8466\/0949\/files\/DRAINS-3_39a9c9b9-961f-49e1-895e-c143a7a499f6.jpg?v=1772652564","url":"https:\/\/aircompressorfactorydirect.com\/products\/castair-all-filters-bowl-float-drain-valve-afd1","provider":"Air Compressor Factory Direct","version":"1.0","type":"link"}