Reviews and General Information on Programmable Thermostats. Remove the wall screws holding up the thermostat before disconnecting the wiring to prevent the wires from falling into the wall. Install the replacement wall plate and hook the new thermostat up to the old wires. Depending on the thermocouple’s type, a thermocouple’s wires may be magnetic. Finally, the 5 wires likely cover Red for 24-volt hot, white for heat, yellow for cooling, green for the fan, and blue for common (common could be another color). Turn on the circuit breaker and test the heater and thermostat for proper op… Fiberglass insulation is great for preventing drafts from affecting thermostat operation. Thermostat Wiring for Dummies. Thermistor motor protection. The manufacturer typically determines this property with a high degree of accuracy, as this is the primary characteristic of interest to thermistor buyers. HSTH-44000. Do not let them fall back in through the hole in … Unused C Wire Terminal. Tighten the terminal screws to secure the wires in place. If your system has both heating and cooling functions, you'll need to connect both the Rc and Rh terminals with a red wire. Green – The green wire connects to the fan. Furnace Thermostat Wiring Diagram Terminal Letters On a Thermostat and What They Control The Hot wire (24 volts) usually Red from the transformer is the main power wire to turn on or off a furnace components. See the diagram below for what each wire controls on your system: Y – Compressor Stage 1 (Cooling) Y2 – Compressor Stage 2 (Cooling) G – Fan C – Common If you have heat and AC, you’ll need 18/5. Step 9. This new wire will serve as the C wire or common wire to provide necessary power to the thermostat. It’s a cheap protective layer that is necessary for all installations. Mount the control unit to the base using the screws included with your thermostat. How to Hook Up a Thermostat: Hook up the wires. The same two wires that connect the thermistor to its excitation source can be used to measure the voltage across the thermistor. Connect the wires to the terminals. The Orange Wire. Now, loop each copper end around each terminal, and tighten the screw on the terminal. Thermistor is a small non-linear resistance sensors, which can be embedded within the insulation of a motor winding, to provide a close thermal association with the winding.It’s made from a metal oxide or semiconductor material. https://www.thermostatcenter.com/ is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com. HSTH-44000, Handheld Infrared Industrial Thermometers, Temperature Connectors, Panels and Block Assemblies, Temperature and Humidity and Dew Point Meters, Multi-Channel Programmable and Universal Input Data Loggers, Safe and precise temperature transmission and control can prevent unplanned production downtime. Please verify your address. Once the new thermostat is on the wall, turn power back on from the breaker. Tighten the screws securely. Connect the wires. A C wire adapter (common wire adapter) is basically a small electronic device, which re-purposes the existing wiring between your thermostat and the furnace, to add a new wire to the system. When you purchase an item through links on our site, we may earn an affiliate commission. Heck, now I’m not calling anyone a dummy! .top-level { In a three-wire installation, connect the red wire to the “R” terminal, the white wire to the “Y” terminal, and the blue wire to the “W” terminal. What I would like you to know is the information detailed below is based on the industry standard, yet not all thermostats will work this way simply because letters and numbers are used as well as color. But what if you have a system that's a little different like a Heat Pump System, Then your thermostat is going to be wired a little different as well. Thermostat Center is supported by our readers. Installing The Wrong Thermostat Type – Always install a thermostat to its compatible base. The orange wire connects to terminal O on your thermostat. View this page in another language or region, Learn more about the  Thermistors are also available with metal or plastic cage-style element covers for air temperature measurement. One is for cool and the other is for heat, hence the abbreviation “RH” and “RC”. The thermistor has to be connected to a control circuit, which can convert the resistance signal, which again has to disconnect the motor. Yellow – The yellow wire connects to your compressor. In this really short video you will learn how to connect an unused wire so it can be used as your C wire, which in a lot of cases has solved the problem of a thermostat not working. Errors were found with the address you provided. The main trouble is dealing with those different colored wires, knowing which one does what and if that wasn’t enough, you also have numbers and letters to deal with. The O/B wire can have many configurations. If you’re still a little confused (and I can understand why you would be), I have added a thermostat wiring made simple video for you to look at which isn’t very long but is one of the best explanations I have come across. The thermostat uses 1 wire to control each of your HVAC system’s primary functions, such as heating, cooling, fan, etc. Mount your new Sensi thermostat base using the supplied screws, drilling holes if necessary.] What is a Thermistor and how does it work? Complete the wire connections on the baseboard heater, if this has not already been done. The wire colors indicate the thermocouple type. 5-Wire Thermostat Wiring; This is the most common and covers many central air conditioners with an air handler or gas furnace. Connecting to a Thermistor These thermistors are pretty hardy, you can strip the PVC insulation and stick the wires into a breadboard or solder to them directly. AND it has been recorded by a professional in the industry. For example, if the Red wire is connected to W on the thermostat … Running New Thermostat Wire – It is possible that you may have to run a new thermostat wire from the air handler or furnace to the location where the existing thermostat is located. Wire the smart thermostat to the correct terminals. Plus, I’m anything but a technician so what I have detailed below is here purely as a guideline. White – The white wire is what connects to the (auxiliary) heat on your system. Safe and precise temperature transmission and control can prevent unplanned production downtime Snap the thermostat to the mounting plate. Since the resistance is pretty high (10Kohm) the wire resistance won't make a … } These letters are standard; hook them up to the same terminals on the new thermostat. It terminates in your outdoor condenser for reversing valve operation from hot to cold. }, Copyright 2003 - 2019 OMEGA Engineering is a subsidiary of Spectris plc. Thermostat wire comes in various weights. So you’ve decided to install your new thermostat and discover that you have an unused wire but you do need a C wire connection. The wire will run through a dedicated opening on the side of the furnace into the control panel. I will explain that in a little more detail further down this page. 4-Wire Thermostat Wiring So 4/4 and 5/5 when dealing with the wire setup. So, this is what you might expect to see in terms of colored wires and what they mean: You may also have up to two black wires as well but these are used for various heating systems in the North or for outdoor purposes, so for most of you these won’t need any attention. If you already have a C wire in place, you just need to connect the same C wire to the new thermostat (when you replace the old model). Connect the remaining supply wire, which is typically white, to the second thermostat wire (typically marked L2 or Line). The orange thermostat wire links to your heat pump, if you have one. Running new thermostat wire can challenging even for professionals. Thermistors are a type of semiconductor, meaning they have greater resistance than conducting materials, but lower resistance than insulating materials. Install new thermostat base. Connect each marked wire to the corresponding terminals on the thermostat with a screwdriver. But you do have a gas, oil or propane conventional forced-air system and a wire labeled G. If you use this option, the G wire will be substituted for your c wire at both your thermostat and HVAC system. Drill a hole in the drywall, and use a fishtape to feed the wire from the furnace through the hole in the wall. If you don’t have a “C” wire: Check the area behind the thermostat to see if a c-wire was tucked into the wall by your electrician or the installer. Screw the system wiring to the screw terminals on the new thermostat using the letter labels as reference (strip the wires back if necessary). Determine your schedule. Mount the baseplate of the smart thermostat to the wall using the provided screws. Tuck the wires into the electrical box and secure the thermostat with the mounting screws. If you have one, that’s your c-wire and you’re ready for general installation. It is very simple and pretty straight forward. How Do You Wire Your Thermistor? 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