{"product_id":"exhaust-fan-20","title":"Exhaust Fan 20\" for Riga XL Greenhouses","description":"\u003cp\u003eThe Riga 20\" Exhaust Fan is the highest-capacity ventilation option in the Riga exhaust fan lineup, engineered specifically for \u003ca href=\"https:\/\/riga-greenhouses.myshopify.com\/collections\/riga-xl-series-greenhouses\" title=\"Riga XL\"\u003eRiga XL\u003c\/a\u003e greenhouses. Its extra-large 20\" blade delivers the high-volume air exchange needed to keep the largest hobby greenhouse structures cool, dry, and productive year-round.\u003c\/p\u003e\n\u003ch2\u003eWhy Proper Greenhouse Ventilation Matters\u003c\/h2\u003e\n\u003cp\u003eWithout active airflow, greenhouse temperatures can climb 20–30°F above outdoor levels on sunny days, triggering heat stress, fungal disease, and crop loss. In an XL-footprint structure, passive roof vents alone are rarely sufficient — a powered exhaust fan mounted high on the back wall creates a negative-pressure draw that pulls fresh air through intake vents at the opposite end, the most effective ventilation strategy for large greenhouse volumes.\u003c\/p\u003e\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e20\" blade diameter\u003c\/strong\u003e — maximum CFM airflow for Riga XL footprints\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRequires a 20.25\" × 20.25\" wall opening\u003c\/strong\u003e — fits standard Riga XL panel cutouts\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePre-wired with a 9-foot grounded power cord\u003c\/strong\u003e — plug-and-play on standard 110–120V household power, no electrician required\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHigh-wall placement\u003c\/strong\u003e — installs near the ridge or above the rear door for maximum heat and humidity extraction\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePairs with a thermostat controller\u003c\/strong\u003e — add automatic temperature management for hands-free climate control\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eCompatible Greenhouse Models\u003c\/h2\u003e\n\u003cp\u003eThis fan is sized and rated for:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eRiga XL greenhouse models\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eFor smaller Riga models, see our \u003ca href=\"https:\/\/riga-greenhouses.myshopify.com\/products\/exhaust-fan-12\" title='12\" Exhaust Fan'\u003e12\" Exhaust Fan\u003c\/a\u003e (Riga 2–4) and \u003ca href=\"https:\/\/riga-greenhouses.myshopify.com\/products\/exhaust-fan-16\" title='16\" Exhaust Fan'\u003e16\" Exhaust Fan\u003c\/a\u003e (Riga 5) options.\u003c\/p\u003e\n\u003ch2\u003eInstallation Overview\u003c\/h2\u003e\n\u003cp\u003eCut a 20.25\" × 20.25\" opening in the polycarbonate panel high on the back wall — typically above the rear door on XL models so the fan can rest on a structural member. Insert the fan, bolt it through the flange holes, and seal the edges with neutral-cure silicone. Pair with passive intake vents or louvers on the front wall near ground level for a full cross-ventilation circuit. Detailed steps are included in the Riga XL assembly manuals; Exaco also provides a dedicated installation video: \u003cem\u003e\"Riga XL Fan Kit Installation Instructions.\"\u003c\/em\u003e\u003c\/p\u003e\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eWhat size opening does the 20\" exhaust fan require?\u003c\/strong\u003e\u003cbr\u003eThe fan requires a 20.25\" × 20.25\" square opening in your greenhouse wall panel.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes this fan need to be hardwired?\u003c\/strong\u003e\u003cbr\u003eNo. It comes pre-wired with a 9-foot grounded plug-in cord and runs on standard 110–120V household power — no electrician required for basic installation.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan I use this fan with a thermostat?\u003c\/strong\u003e\u003cbr\u003eYes, and it is highly recommended. A thermostat controller automatically turns the fan on and off based on your target temperature. If you also use an intake shutter vent, a simple plug splitter lets both units run from the same thermostat.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhere should I mount the fan?\u003c\/strong\u003e\u003cbr\u003eHigh on the back (leeward) wall, ideally above the rear door on XL models so it rests on a structural member. Position it opposite or diagonal from an intake vent to create an effective cross-breeze.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes the 20\" fan come with a warranty?\u003c\/strong\u003e\u003cbr\u003eYes. It carries the manufacturer’s standard warranty (typically 2 years on the motor, 1 year on other parts). It is not covered under the Riga greenhouse’s 10–15 year structural warranty.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the difference between the 12\", 16\", and 20\" exhaust fans?\u003c\/strong\u003e\u003cbr\u003eThe 12\" fan fits Riga 2–4 and Victorian J-Vic\/VI models; the 16\" fan fits the Riga 5 and Victorian VI 34–46; and the 20\" fan is designed exclusively for the Riga XL. Choose based on your greenhouse model for optimal airflow.\u003c\/p\u003e","brand":"Exaco","offers":[{"title":"Default Title","offer_id":59770633814302,"sku":"VES 20 C","price":425.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1078\/1802\/5246\/files\/Exhaust_2.webp?v=1786648234","url":"https:\/\/rigagreenhousekit.com\/products\/exhaust-fan-20","provider":"Riga Greenhouses","version":"1.0","type":"link"}