{"product_id":"gavita-fb1-ec-fan-balancer","title":"Gavita FB1 EC Fan Balancer – Grow Room Fan Controller","description":"\u003ch2\u003eBalance Intake Against Extraction From One Gavita Fan Signal\u003c\/h2\u003e\u003cp\u003eThe \u003cstrong\u003eGavita FB1 EC Fan Balancer\u003c\/strong\u003e is a compact add-on module that works \u003cstrong\u003eonly with a Gavita EL1F or EL2F Master Controller\u003c\/strong\u003e – the fan-control models. It cannot run fans on its own: it takes the controller's fan signal and splits it in two: the \u003cstrong\u003eOutput\u003c\/strong\u003e runs your \u003cstrong\u003eextraction fan\u003c\/strong\u003e exactly as the controller commands, while the \u003cstrong\u003eOffset Output\u003c\/strong\u003e runs your \u003cstrong\u003eintake fan\u003c\/strong\u003e at a lower speed you set on the dial, anywhere from \u003cstrong\u003e0% to 70% below\u003c\/strong\u003e the extractor. The controller keeps its automatic PID fan control for temperature and humidity, and the FB1 simply holds the gap between the two fans as their speed rises and falls.\u003c\/p\u003e\u003ch3\u003eKey Benefits\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eTwo fans from one control signal\u003c\/strong\u003e – one input feeds a direct output and an offset output.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e0 to −70% offset\u003c\/strong\u003e on the intake fan, set on a single rotary dial.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe controller stays in charge\u003c\/strong\u003e – the Master Controller still ramps both fans automatically, and the balance holds at every speed.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBalances two identical fans\u003c\/strong\u003e – no need to buy a smaller intake fan or choke the intake duct to create negative pressure.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSuits EC fans of any size\u003c\/strong\u003e; AC fans connect through Gavita's EFM1 module.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eOver-Pressure and Escaping Odours\u003c\/h3\u003e\u003cp\u003eCarbon filters, silencers and long duct runs all slow the extraction side, so an intake fan matched to the extractor often pushes in more air than the extractor can pull out. The room drifts into positive pressure: tent walls bulge, warm humid air and odours leak out through every seam and gap, and \u003cstrong\u003eairflow\u003c\/strong\u003e across the canopy turns uneven. Running the intake fan slower than the extractor keeps the grow room under slight \u003cstrong\u003enegative pressure\u003c\/strong\u003e, so fresh air comes in where you want it and stale air leaves through the filter. The FB1 sets that difference once, on a dial, and keeps it in step with the controller from lights-on to lights-off.\u003c\/p\u003e\u003ch3\u003eHow to Use\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eConnect the FB1's \u003cstrong\u003eInput\u003c\/strong\u003e to the fan output of your Gavita Master Controller (\u003cstrong\u003eEL1F\u003c\/strong\u003e or \u003cstrong\u003eEL2F\u003c\/strong\u003e).\u003c\/li\u003e\n\u003cli\u003eConnect the \u003cstrong\u003eextraction fan\u003c\/strong\u003e to \u003cstrong\u003eOutput\u003c\/strong\u003e and the \u003cstrong\u003eintake fan\u003c\/strong\u003e to \u003cstrong\u003eOffset Output\u003c\/strong\u003e.\u003c\/li\u003e\n\u003cli\u003eStart with the dial at \u003cstrong\u003e0%\u003c\/strong\u003e and turn it towards \u003cstrong\u003e−70%\u003c\/strong\u003e until the tent walls draw in slightly or a door shows a gentle inward pull.\u003c\/li\u003e\n\u003cli\u003eLeave the controller to manage temperature and humidity as normal – the offset follows every speed change.\u003c\/li\u003e\n\u003cli\u003eRunning AC fans? Fit Gavita's \u003cstrong\u003eEFM1\u003c\/strong\u003e module to bring them under the controller.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cdiv class=\"hcs-specs\"\u003e\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Gavita\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eModel:\u003c\/strong\u003e FB1 EC Fan Balancer (UK)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eType:\u003c\/strong\u003e Fan balancer \/ fan controller module\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInput:\u003c\/strong\u003e 1 – fan signal from a Gavita Master Controller\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOutputs:\u003c\/strong\u003e 2 – Output (follows the controller) and Offset Output\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOffset range:\u003c\/strong\u003e 0% to −70%, rotary dial\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFan type:\u003c\/strong\u003e EC fans of any size; AC fans via the Gavita EFM1 module\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompatible controllers:\u003c\/strong\u003e Gavita Master Controller EL1F and EL2F only (not the lighting-only EL1 or EL2)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFan control retained:\u003c\/strong\u003e the controller's automatic PID fan speed control\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cdiv class=\"hcs-faq\"\u003e\n\u003cdetails style=\"border:1px solid #e6e6e6;border-radius:8px;padding:12px 16px;margin:0 0 8px;\"\u003e\u003csummary style=\"cursor:pointer;font-weight:600;\"\u003eWhich Gavita controllers does the FB1 work with?\u003c\/summary\u003e\u003cp style=\"margin:10px 0 0;\"\u003eThe fan-control Master Controllers, the EL1F and EL2F. The FB1 splits the controller's fan signal, so a lighting-only EL1 or EL2 – which has no fan output – cannot drive it.\u003c\/p\u003e\u003c\/details\u003e\u003cdetails style=\"border:1px solid #e6e6e6;border-radius:8px;padding:12px 16px;margin:0 0 8px;\"\u003e\u003csummary style=\"cursor:pointer;font-weight:600;\"\u003eWhich fan goes on the offset output?\u003c\/summary\u003e\u003cp style=\"margin:10px 0 0;\"\u003eThe intake fan. The extractor runs at the speed the controller asks for and the intake follows it, reduced by the offset you dial in, which keeps the room under slight negative pressure.\u003c\/p\u003e\u003c\/details\u003e\u003cdetails style=\"border:1px solid #e6e6e6;border-radius:8px;padding:12px 16px;margin:0 0 8px;\"\u003e\u003csummary style=\"cursor:pointer;font-weight:600;\"\u003eCan I use it with AC fans?\u003c\/summary\u003e\u003cp style=\"margin:10px 0 0;\"\u003eIt is built for EC fans. AC fans need Gavita's EFM1 module before the Master Controller can control them.\u003c\/p\u003e\u003c\/details\u003e\u003cdetails style=\"border:1px solid #e6e6e6;border-radius:8px;padding:12px 16px;margin:0 0 8px;\"\u003e\u003csummary style=\"cursor:pointer;font-weight:600;\"\u003eHow much offset should I set?\u003c\/summary\u003e\u003cp style=\"margin:10px 0 0;\"\u003eIt depends on the filter, ducting and fan sizes. Start at 0%, increase the offset until the tent walls just pull inwards, and stop there – too much offset starves the room of fresh air.\u003c\/p\u003e\u003c\/details\u003e\n\u003c\/div\u003e\u003ch3\u003eWorks Well With\u003c\/h3\u003e\u003cdiv class=\"hcs-related\" style=\"display:flex;flex-wrap:wrap;gap:10px;margin:12px 0 0;\"\u003e\n\u003ca href=\"\/products\/gas-gavita-male-to-male-5m-pack-10\" style=\"flex:1 1 240px;display:flex;align-items:center;gap:12px;padding:10px 12px;border:1px solid #e6e6e6;border-radius:8px;text-decoration:none;color:inherit;background:#fff;\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0748\/7127\/5786\/files\/fan-controller-gas-digital-ec-cable-pack-10-connect-gas-to-gavita-31261546709176.webp?v=1773496828\u0026amp;width=160\" alt=\"G.A.S Gavita EC Cable Pack 10\" width=\"64\" height=\"64\" loading=\"lazy\" style=\"width:64px;height:64px;object-fit:contain;flex:none;\"\u003e\u003cspan style=\"font-size:14px;line-height:1.4;\"\u003e\u003cstrong style=\"display:block;\"\u003eG.A.S Gavita EC Cable Pack 10\u003c\/strong\u003e\u003cspan style=\"color:#008d37;\"\u003e5m lead from EC fan to Gavita balancer\u003c\/span\u003e\u003c\/span\u003e\u003c\/a\u003e\u003ca href=\"\/products\/revolution-vector-ec-fan\" style=\"flex:1 1 240px;display:flex;align-items:center;gap:12px;padding:10px 12px;border:1px solid #e6e6e6;border-radius:8px;text-decoration:none;color:inherit;background:#fff;\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0748\/7127\/5786\/files\/revolution-vector-ec-fan-1.png?v=1789231860\u0026amp;width=160\" alt=\"Revolution EC Vector Inline Extractor Fan\" width=\"64\" height=\"64\" loading=\"lazy\" style=\"width:64px;height:64px;object-fit:contain;flex:none;\"\u003e\u003cspan style=\"font-size:14px;line-height:1.4;\"\u003e\u003cstrong style=\"display:block;\"\u003eRevolution EC Vector Inline Extractor Fan\u003c\/strong\u003e\u003cspan style=\"color:#008d37;\"\u003eSystemair EC fan for intake or extraction\u003c\/span\u003e\u003c\/span\u003e\u003c\/a\u003e\n\u003c\/div\u003e","brand":"Gavita","offers":[{"title":"Default Title","offer_id":53931120361738,"sku":"ENV-GAV1-001-01","price":75.9,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0748\/7127\/5786\/files\/gavita-fb1-ec-fan-balancer-default-title-1.jpg?v=1792296089","url":"https:\/\/hydrocropshop.co.uk\/products\/gavita-fb1-ec-fan-balancer","provider":"Hydro Crop Shop","version":"1.0","type":"link"}