{"product_id":"new-for-carrier-2pipe-tms910sa-4pipe-tms910sfa-fan-coil-room-thermostat","title":"Carrier Room Thermostat TMS910SA","description":"\u003c!-- SEO Introduction --\u003e\n\u003cdiv class=\"koeed-container\" style=\"line-height: 1.6; color: #333; width: 100%;\"\u003e\n    \u003ch2 style=\"color: #0056b3; border-left: 5px solid #16c8c8; padding-left: 15px; margin-top: 0;\"\u003eCarrier TMS910SA Digital Room Thermostat\u003c\/h2\u003e\n    \u003cp\u003e\n        The \u003cstrong\u003eCarrier TMS910SA\u003c\/strong\u003e is a premium, wall-mounted digital room thermostat specifically designed for the precise control of Fan Coil Units (FCU) in commercial, hotel, and residential HVAC systems. Featuring a clear, easy-to-read LCD display, it provides intuitive temperature management to maximize indoor comfort while optimizing energy consumption.\n    \u003c\/p\u003e\n    \u003cp\u003e\n        Engineered for standard 2-pipe or 4-pipe FCU configurations, the TMS910SA effectively controls 3-speed fans (High, Medium, Low, Auto) and motorized on\/off valves. Its built-in precision NTC thermistor continuously monitors room temperature, seamlessly bridging the gap between user comfort preferences and mechanical system responses.\n    \u003c\/p\u003e\n\n    \u003c!-- Technical Specifications --\u003e\n    \u003ch3 style=\"color: #0056b3;\"\u003eDetailed Technical Specifications\u003c\/h3\u003e\n    \u003cdiv style=\"overflow-x: auto;\"\u003e\n        \u003ctable style=\"width: 100%; border-collapse: collapse; margin: 20px 0; border: 1px solid #eeeeee;\"\u003e\n            \u003cthead\u003e\n                \u003ctr style=\"background-color: #16c8c8; color: white;\"\u003e\n                    \u003cth style=\"padding: 12px; text-align: left; border: 1px solid #eeeeee;\"\u003eParameter\u003c\/th\u003e\n                    \u003cth style=\"padding: 12px; text-align: left; border: 1px solid #eeeeee;\"\u003eSpecification Data\u003c\/th\u003e\n                \u003c\/tr\u003e\n            \u003c\/thead\u003e\n            \u003ctbody\u003e\n                \u003ctr style=\"background-color: #f4fcfc;\"\u003e\n                    \u003ctd style=\"padding: 10px; border: 1px solid #eeeeee; font-weight: bold;\"\u003eBrand \u0026amp; Model\u003c\/td\u003e\n                    \u003ctd style=\"padding: 10px; border: 1px solid #eeeeee;\"\u003eCarrier \/ TMS910SA\u003c\/td\u003e\n                \u003c\/tr\u003e\n                \u003ctr style=\"background-color: #fafafa;\"\u003e\n                    \u003ctd style=\"padding: 10px; border: 1px solid #eeeeee; font-weight: bold;\"\u003eSystem Compatibility\u003c\/td\u003e\n                    \u003ctd style=\"padding: 10px; border: 1px solid #eeeeee;\"\u003eFan Coil Units (FCU) - 2-pipe \/ 4-pipe systems\u003c\/td\u003e\n                \u003c\/tr\u003e\n                \u003ctr style=\"background-color: #f4fcfc;\"\u003e\n                    \u003ctd style=\"padding: 10px; border: 1px solid #eeeeee; font-weight: bold;\"\u003eOperating Voltage\u003c\/td\u003e\n                    \u003ctd style=\"padding: 10px; border: 1px solid #eeeeee;\"\u003e220V - 240V AC, 50\/60 Hz\u003c\/td\u003e\n                \u003c\/tr\u003e\n                \u003ctr style=\"background-color: #fafafa;\"\u003e\n                    \u003ctd style=\"padding: 10px; border: 1px solid #eeeeee; font-weight: bold;\"\u003eRelay Contact Rating\u003c\/td\u003e\n                    \u003ctd style=\"padding: 10px; border: 1px solid #eeeeee;\"\u003eFan: Max 3A (Inductive) | Valve: Max 2A\u003c\/td\u003e\n                \u003c\/tr\u003e\n                \u003ctr style=\"background-color: #f4fcfc;\"\u003e\n                    \u003ctd style=\"padding: 10px; border: 1px solid #eeeeee; font-weight: bold;\"\u003eTemperature Setting Range\u003c\/td\u003e\n                    \u003ctd style=\"padding: 10px; border: 1px solid #eeeeee;\"\u003e5°C to 35°C (Programmable setpoint)\u003c\/td\u003e\n                \u003c\/tr\u003e\n                \u003ctr style=\"background-color: #fafafa;\"\u003e\n                    \u003ctd style=\"padding: 10px; border: 1px solid #eeeeee; font-weight: bold;\"\u003eSensing Element\u003c\/td\u003e\n                    \u003ctd style=\"padding: 10px; border: 1px solid #eeeeee;\"\u003ePrecision NTC (Negative Temperature Coefficient) Thermistor\u003c\/td\u003e\n                \u003c\/tr\u003e\n                \u003ctr style=\"background-color: #f4fcfc;\"\u003e\n                    \u003ctd style=\"padding: 10px; border: 1px solid #eeeeee; font-weight: bold;\"\u003eMounting \/ Installation\u003c\/td\u003e\n                    \u003ctd style=\"padding: 10px; border: 1px solid #eeeeee;\"\u003eStandard 86x86 mm flush wall box\u003c\/td\u003e\n                \u003c\/tr\u003e\n                \u003ctr style=\"background-color: #fafafa;\"\u003e\n                    \u003ctd style=\"padding: 10px; border: 1px solid #eeeeee; font-weight: bold;\"\u003eKey Features\u003c\/td\u003e\n                    \u003ctd style=\"padding: 10px; border: 1px solid #eeeeee;\"\u003e3-Speed Fan Control, Cool\/Heat\/Vent modes, Sleep function\u003c\/td\u003e\n                \u003c\/tr\u003e\n            \u003c\/tbody\u003e\n        \u003c\/table\u003e\n    \u003c\/div\u003e\n\n    \u003c!-- Application \u0026 Reliability --\u003e\n    \u003ch3 style=\"color: #0056b3;\"\u003eHVAC Application \u0026amp; Reliability\u003c\/h3\u003e\n    \u003cp\u003e\n        The TMS910SA acts as the central command node for individual room climate control. Its robust internal relay structure ensures longevity even with the frequent switching cycles characteristic of commercial HVAC operation.\n    \u003c\/p\u003e\n    \u003cul\u003e\n        \u003cli\u003e\n\u003cstrong\u003eCommercial Offices \u0026amp; Hotels:\u003c\/strong\u003e The intuitive interface reduces user-error calls to facility management. The \"Auto\" fan speed setting seamlessly modulates airflow based on the temperature differential, reducing draft and acoustic noise.\u003c\/li\u003e\n        \u003cli\u003e\n\u003cstrong\u003eEnergy Conservation:\u003c\/strong\u003e Built-in sleep and energy-saving modes prevent excessive cooling or heating when the space is unoccupied, aligning with modern green building standards.\u003c\/li\u003e\n    \u003c\/ul\u003e\n\n    \u003c!-- Koeed B2B Tool: NTC Thermistor Calculator --\u003e\n    \u003cdiv id=\"koeed-hvac-tool\" style=\"background: #f9f9f9; border: 2px solid #16c8c8; border-radius: 8px; padding: 20px; margin: 30px 0;\"\u003e\n        \u003ch3 style=\"margin-top: 0; color: #16c8c8;\"\u003eFAE Tool: NTC 10K Sensor Diagnostic Calculator\u003c\/h3\u003e\n        \u003cp style=\"font-size: 0.9em; color: #666;\"\u003eIs your Carrier thermostat displaying a wildly inaccurate room temperature? The internal NTC sensor may have drifted. Disconnect power, use your multimeter to measure the Ohms (Ω) across the sensor terminals, and input the value below to see what temperature the thermostat \u003cem\u003ethinks\u003c\/em\u003e the room is.\u003c\/p\u003e\n        \n        \u003cdiv style=\"display: flex; flex-wrap: wrap; gap: 15px; margin-bottom: 15px;\"\u003e\n            \u003cdiv style=\"flex: 1; min-width: 200px;\"\u003e\n                \u003clabel style=\"display: block; font-weight: bold; margin-bottom: 5px;\"\u003eMeasured Resistance (Ohms Ω):\u003c\/label\u003e\n                \u003cinput type=\"number\" id=\"koeed-ohm-input\" value=\"10000\" min=\"500\" max=\"100000\" style=\"width: 100%; padding: 8px; border: 1px solid #ccc; border-radius: 4px; box-sizing: border-box;\"\u003e\n                \u003csmall style=\"color: #888;\"\u003e*A healthy standard HVAC sensor reads 10,000 Ω at 25°C (77°F).\u003c\/small\u003e\n            \u003c\/div\u003e\n            \u003cdiv style=\"flex: 1; min-width: 200px;\"\u003e\n                \u003clabel style=\"display: block; font-weight: bold; margin-bottom: 5px;\"\u003eStandard Beta (B) Value:\u003c\/label\u003e\n                \u003cselect id=\"koeed-beta-input\" style=\"width: 100%; padding: 8px; border: 1px solid #ccc; border-radius: 4px; box-sizing: border-box;\"\u003e\n                    \u003coption value=\"3950\"\u003e3950 (Typical HVAC Standard)\u003c\/option\u003e\n                    \u003coption value=\"3435\"\u003e3435\u003c\/option\u003e\n                    \u003coption value=\"3380\"\u003e3380\u003c\/option\u003e\n                \u003c\/select\u003e\n            \u003c\/div\u003e\n        \u003c\/div\u003e\n        \n        \u003cbutton onclick=\"koeedCalculateNTC()\" style=\"background: #16c8c8; color: white; border: none; padding: 12px 24px; border-radius: 4px; cursor: pointer; font-weight: bold; transition: background 0.3s;\"\u003eCalculate Sensed Temperature\u003c\/button\u003e\n        \n        \u003cdiv id=\"koeed-ntc-results\" style=\"margin-top: 20px; padding: 15px; background: white; border-radius: 4px; border-left: 5px solid #0056b3; display: none; box-shadow: 0 2px 4px rgba(0,0,0,0.05);\"\u003e\n            \u003cdiv style=\"margin-bottom: 10px;\"\u003e\n\u003cstrong\u003eCalculated Temperature (Celsius):\u003c\/strong\u003e \u003cspan id=\"koeed-cel-out\" style=\"color: #0056b3; font-weight: bold; font-size: 1.2em;\"\u003e\u003c\/span\u003e\n\u003c\/div\u003e\n            \u003cdiv style=\"margin-bottom: 10px;\"\u003e\n\u003cstrong\u003eCalculated Temperature (Fahrenheit):\u003c\/strong\u003e \u003cspan id=\"koeed-fah-out\" style=\"color: #d32f2f; font-weight: bold; font-size: 1.2em;\"\u003e\u003c\/span\u003e\n\u003c\/div\u003e\n            \u003cp id=\"koeed-diag-msg\" style=\"font-size: 0.9em; color: #555; margin-top: 10px; border-top: 1px solid #eee; padding-top: 10px;\"\u003e\u003c\/p\u003e\n        \u003c\/div\u003e\n\n        \u003cnoscript\u003e\n            \u003cp\u003e\u003cstrong\u003eSEO Tool Formula:\u003c\/strong\u003e This calculator uses the simplified Steinhart-Hart (Beta parameter) equation for NTC thermistors. For an NTC 10K sensor with a Beta of 3950: if your multimeter reads 12,500 Ohms, the perceived temperature is approximately 19.8°C (67.6°F). A reading of 0 Ohms (short) or Infinite Ohms (open circuit) means the sensor has critically failed and the thermostat must be replaced.\u003c\/p\u003e\n        \u003c\/noscript\u003e\n    \u003c\/div\u003e\n\n    \u003cscript\u003e\n        function koeedCalculateNTC() {\n            const r_measured = parseFloat(document.getElementById('koeed-ohm-input').value);\n            const beta = parseFloat(document.getElementById('koeed-beta-input').value);\n            \n            const resultsBox = document.getElementById('koeed-ntc-results');\n            const diagMsg = document.getElementById('koeed-diag-msg');\n\n            if (isNaN(r_measured) || r_measured \u003c= 0) {\n                alert(\"Please enter a valid resistance value in Ohms.\");\n                return;\n            }\n\n            \/\/ Constants for NTC 10K\n            const r_ref = 10000; \/\/ 10K Ohms at 25C\n            const t_ref_kelvin = 298.15; \/\/ 25 Celsius in Kelvin\n\n            \/\/ Beta Parameter Equation: 1\/T = 1\/T0 + (1\/B) * ln(R\/R0)\n            const ln_ratio = Math.log(r_measured \/ r_ref);\n            const t_kelvin = 1 \/ ((1 \/ t_ref_kelvin) + (ln_ratio \/ beta));\n            \n            \/\/ Convert to Celsius and Fahrenheit\n            const t_celsius = t_kelvin - 273.15;\n            const t_fahrenheit = (t_celsius * 9\/5) + 32;\n\n            document.getElementById('koeed-cel-out').innerHTML = t_celsius.toFixed(1) + \" °C\";\n            document.getElementById('koeed-fah-out').innerHTML = t_fahrenheit.toFixed(1) + \" °F\";\n            \n            \/\/ Diagnostic Logic\n            if (r_measured \u003c 500) {\n                diagMsg.innerHTML = \"⚠️ \u003cstrong\u003eDiagnostic Warning:\u003c\/strong\u003e Extremely low resistance indicates a near short-circuit. The thermostat will likely show an Error code (e.g., E1) or read max temperature.\";\n            } else if (r_measured \u003e 90000) {\n                diagMsg.innerHTML = \"⚠️ \u003cstrong\u003eDiagnostic Warning:\u003c\/strong\u003e Extremely high resistance indicates an open circuit or broken sensor trace. The thermostat will likely read negative or minimum temperature.\";\n            } else {\n                diagMsg.innerHTML = `\u003cstrong\u003eField Check:\u003c\/strong\u003e If the calculated ${t_celsius.toFixed(1)}°C deviates by more than 2°C from the actual room temperature (measured with an independent thermometer), the internal sensor is degraded and the thermostat should be replaced.`;\n            }\n\n            resultsBox.style.display = 'block';\n        }\n    \u003c\/script\u003e\n\n    \u003c!-- Troubleshooting FAQ --\u003e\n    \u003ch3 style=\"color: #0056b3;\"\u003eMaintenance \u0026amp; Troubleshooting FAQ\u003c\/h3\u003e\n    \u003cp\u003e\u003cstrong\u003e1. The thermostat screen is completely blank. How do I fix this?\u003c\/strong\u003e\u003cbr\u003e\n    The TMS910SA is hardwired and does not use batteries. A blank screen means a loss of 220V AC power. Check the main HVAC circuit breaker. If the breaker is on, use a multimeter to verify 220V is reaching the Line (L) and Neutral (N) terminals on the backplate. If voltage is present but the screen is dead, the internal power supply board has failed.\u003c\/p\u003e\n    \n    \u003cp\u003e\u003cstrong\u003e2. The fan runs continuously, but the room isn't cooling down.\u003c\/strong\u003e\u003cbr\u003e\n    First, ensure the thermostat is set to \"Cool\" mode and the setpoint is lower than the room temperature. Listen for a distinct \"click\" from the thermostat—this is the relay engaging to open the chilled water valve. If you hear the click but no cooling happens, the issue is likely a stuck motorized valve in the ceiling, not the thermostat. You can verify this by checking if 220V is being sent out from the Valve Open terminal.\u003c\/p\u003e\n\n    \u003cp\u003e\u003cstrong\u003e3. The temperature displayed on the screen jumps around randomly.\u003c\/strong\u003e\u003cbr\u003e\n    Fluctuating temperature readings usually point to a failing NTC thermistor or condensation\/dust buildup on the sensor circuit. You can remove the front cover and gently blow compressed air over the sensor tip. If the problem persists, the sensor resistance is drifting, and the unit requires replacement.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003c!-- Structured Data --\u003e\n\u003cscript type=\"application\/ld+json\"\u003e\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"FAQPage\",\n  \"mainEntity\": [\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Why is my Carrier TMS910SA thermostat screen blank?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"The thermostat is hardwired for 220V AC. A blank screen indicates a loss of power. Check the circuit breaker and use a multimeter to verify voltage at the L and N terminals. If voltage is present, the thermostat's internal power board has failed.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Why is the FCU fan running but there is no cooling?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"If the thermostat is set to cool and 'clicks' (relay engaging), but there is no cooling, the motorized water valve in the ceiling fan coil unit is likely stuck closed or its actuator has failed. Verify 220V output from the thermostat valve terminal.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Why is the displayed room temperature fluctuating randomly?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"This is often caused by a failing internal NTC thermistor, or moisture\/dust bridging the sensor connections. Clean the sensor area gently. If the reading remains unstable, the thermostat must be replaced.\"\n      }\n    }\n  ]\n}\n\u003c\/script\u003e\n\n\u003cscript type=\"application\/ld+json\"\u003e\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"WebApplication\",\n  \"name\": \"HVAC NTC 10K Sensor Diagnostic Calculator\",\n  \"description\": \"Calculates the perceived room temperature based on the measured Ohmic resistance of an NTC 10K thermistor, assisting in the diagnosis of faulty HVAC thermostats.\",\n  \"applicationCategory\": \"EngineeringTool\",\n  \"operatingSystem\": \"Any\"\n}\n\u003c\/script\u003e","brand":"CARRIER","offers":[{"title":"Default Title","offer_id":44402413732025,"sku":"185985384219","price":82.88,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0268\/8476\/7929\/files\/s-l1600_4581283b-c262-4953-8ab0-f641f66419a9.jpg?v=1723082099","url":"https:\/\/koeed.com\/pl\/products\/new-for-carrier-2pipe-tms910sa-4pipe-tms910sfa-fan-coil-room-thermostat","provider":"KOEED","version":"1.0","type":"link"}