{"product_id":"resideo-braukmann-tr21-a-10k-ohm-ntc-non-linear-temperature-wall-module-for-averaging","title":"Resideo Braukmann tr21-a 10K Ohm Ntc Non-linear Temperature Wall Module for Averaging","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\u003cp\u003eThe Resideo Braukmann TR21-A is a 10K ohm NTC non-linear temperature wall module designed specifically for use in averaging applications with multiple sensors. This direct-wired wall module is part of the TR21 through TR24 family, all of which include an integrated space temperature sensor. The TR21-A is intended for installation in commercial and light industrial HVAC systems where accurate zone temperature averaging is required across multiple measurement points. It is not a standalone thermostat and does not include a separate external sensor. The module itself serves as the sensor in a parallel averaging circuit, using a unique 10K ohm non-linear thermistor formed by two 20K ohm resistors wired in parallel. This configuration is specifically engineered to deliver consistent, reliable temperature averaging when multiple TR21-A units are connected together on a shared input. HVAC technicians and building automation specialists rely on this type of wall module when a single-point temperature reading is not sufficient to represent zone conditions accurately, such as in large open spaces, corridors, or multi-zone averaging loops. The TR21-A is compatible with a broad range of Honeywell and Resideo controllers, including Spyder Unitary Controllers, Excel 600, 500, 100, and 80 controllers, Excel 10 W7750, W7751A, W7752, and W7753 controllers, the W7761 Controller, and Excel 10 and 15 Series Controllers. It can also be used with T7350 and TB8220 thermostats. The module mounts on a standard 2 by 4 inch junction box or on a 60 mm diameter junction box, making field installation straightforward. Its white housing blends cleanly into commercial wall surfaces. Operating humidity range is 5 to 95 percent RH, non-condensing, and the operating temperature range spans 45 F to 99 F, covering typical occupied space conditions. The physical dimensions are 4 and 13\/16 inches high, 3 inches wide, and 7\/8 inches deep.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eUnique 10K ohm non-linear NTC thermistor formed by two 20K ohm resistors in parallel, optimized for multi-sensor averaging circuits\u003c\/li\u003e\n\u003cli\u003eCompatible with Spyder, Excel 600, 500, 100, 80, Excel 10 and 15 Series Controllers, W7761, T7350, and TB8220 Thermostats\u003c\/li\u003e\n\u003cli\u003eMounts on a standard 2 by 4 inch or 60 mm diameter junction box for straightforward field installation\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eProduct Highlights\u003c\/h4\u003e\u003cp\u003eThe Resideo Braukmann TR21-A delivers accurate, stable zone temperature averaging for commercial HVAC building automation systems. Its broad controller compatibility and simple junction box mounting make it a dependable choice for HVAC technicians working with Honeywell and Resideo control platforms.\u003c\/p\u003e\u003ch3\u003eProduct Information\u003c\/h3\u003e\u003ch4\u003eStandard Information\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand\u003c\/strong\u003e: RESIDEO BRAUKMANN\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: TR21-A\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSensor Type\u003c\/strong\u003e: 10K ohm NTC non-linear, two 20K ohm resistors in parallel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplication\u003c\/strong\u003e: For use only when averaging multiple sensors\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eColor\u003c\/strong\u003e: White\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMounting\u003c\/strong\u003e: Standard 2 by 4 inch junction box or 60 mm diameter junction box\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOperating Humidity Range\u003c\/strong\u003e: 5 to 95 percent RH, non-condensing\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOperating Temperature Range\u003c\/strong\u003e: 45 F to 99 F\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDimensions\u003c\/strong\u003e: 4 and 13\/16 inches high by 3 inches wide by 7\/8 inches deep\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompatible Controllers\u003c\/strong\u003e: Spyder, Excel 600, 500, 100, 80, Excel 10 and 15 Series, W7761, W7750, W7751A, W7752, W7753\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompatible Thermostats\u003c\/strong\u003e: T7350, TB8220\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"RESIDEO","offers":[{"title":"Default Title","offer_id":51120826057010,"sku":"TR21-A","price":145.68,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/304881558.jpg?v=1778781666","url":"https:\/\/voomisupply.com\/products\/resideo-braukmann-tr21-a-10k-ohm-ntc-non-linear-temperature-wall-module-for-averaging","provider":"Voomi Supply","version":"1.0","type":"link"}