{"product_id":"coolautomation-gs-smt-hoa-underfloor-heating-controller","title":"CoolAutomation GS-SMT-HOA underfloor heating controller, 8 zones, Modbus RTU","description":"\u003cp\u003eThe CoolAutomation GS-SMT-HOA is an 8-zone controller for hydronic and electric underfloor (radiant floor) heating. Each zone has its own 10K temperature sensor input, setpoint and relay output, and every zone appears as a separate unit in home automation, BMS and the CoolAutomation apps when the board is connected to a CoolMaster, CoolMasterPro, CoolMaster EDGE or CooLinkBridge.\u003c\/p\u003e\n\u003cp\u003eRelays are dry contacts rated 5 A up to 230 V AC, so they can drive zone valves, actuators or contactors directly, and each has an On \/ Off \/ Auto override switch for commissioning and service. A general output closes whenever any zone calls for heat, ready to start the boiler or pump. Communication is Modbus RTU over RS485.\u003c\/p\u003e\n\u003ch3\u003eKey Features\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e8 independent zones, each with 10K temperature sensor input, setpoint and relay output\u003c\/li\u003e\n\u003cli\u003eDry-contact relays, 5 A, up to 230 V AC, with On \/ Off \/ Auto override switch per relay\u003c\/li\u003e\n\u003cli\u003eGeneral heat-demand output, active when at least one zone is on\u003c\/li\u003e\n\u003cli\u003e2 × 0–10 V DC analog outputs\u003c\/li\u003e\n\u003cli\u003eModbus RTU over RS485; DIP-switch address and end-of-line resistor\u003c\/li\u003e\n\u003cli\u003eUp to 4 boards (32 zones) per CoolMaster or CooLinkBridge, 8 boards (64 zones) per CoolMaster EDGE, 10 boards (80 zones) per CoolMasterPro\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eTypical Applications\u003c\/h3\u003e\n\u003cp\u003eHomes, hotels and spas with hydronic radiant floors or electric floor heating, where floor zones and VRF\/split air conditioning are controlled from the same KNX, BMS or home automation system.\u003c\/p\u003e\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003ctable\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower supply\u003c\/td\u003e\n\u003ctd\u003e24 V DC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower consumption\u003c\/td\u003e\n\u003ctd\u003e0.5 A\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eZone inputs\u003c\/td\u003e\n\u003ctd\u003e8 × 10K type 2 temperature sensor (or binary input)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eZone outputs\u003c\/td\u003e\n\u003ctd\u003e8 × relay, dry contact, 5 A, up to 230 V AC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAnalog outputs\u003c\/td\u003e\n\u003ctd\u003e2 × 0–10 V DC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCommunication\u003c\/td\u003e\n\u003ctd\u003eRS485, Modbus RTU; 2-wire shielded polarized twisted pair, 20–24 AWG\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMax bus wiring length\u003c\/td\u003e\n\u003ctd\u003e800 m (2600 ft)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDimensions (H × W × D)\u003c\/td\u003e\n\u003ctd\u003e19 × 210 × 120 mm (0.75 × 7.8 × 4.72 in)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.12 kg (0.26 lb)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating temperature\u003c\/td\u003e\n\u003ctd\u003e-10 °C to +50 °C (14 °F to 122 °F), 0–80 % RH\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCertifications\u003c\/td\u003e\n\u003ctd\u003eNot UL\/NRTL listed\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eManufacturer part no.\u003c\/td\u003e\n\u003ctd\u003eGS-SMT-HOA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\n\u003ch3\u003eRelated Products\u003c\/h3\u003e\n\u003cp\u003eCoolMaster, CoolMasterPro, CoolMaster EDGE, and their KNX versions for bringing underfloor heating zones into KNX alongside VRF.\u003c\/p\u003e\n\u003cp\u003e\u003cem\u003eNot UL\/NRTL listed — relay outputs can switch line-voltage loads; installation by a licensed electrician to local code. Verify local code requirements before specifying in US installations.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0673\/4161\/5360\/files\/CoolAutomation_GS-SMT-HOA_datasheet_KNXSupply.pdf\" target=\"_blank\" rel=\"noopener\"\u003eDatasheet (PDF)\u003c\/a\u003e · \u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0673\/4161\/5360\/files\/CoolAutomation_GS-SMT-HOA_wiring_details_KNXSupply.pdf\" target=\"_blank\" rel=\"noopener\"\u003eWiring details (PDF)\u003c\/a\u003e · Available to order.\u003c\/p\u003e","brand":"CoolAutomation","offers":[{"title":"Default Title","offer_id":50616581783808,"sku":"GS-SMT-HOA","price":873.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0673\/4161\/5360\/files\/Group-30872.png?v=1791979241","url":"https:\/\/www.knxsupply.com\/products\/coolautomation-gs-smt-hoa-underfloor-heating-controller","provider":"KNX Supply","version":"1.0","type":"link"}