C-Wire Check product guide
ecobee Smart Thermostat Premium with SmartSensor
24 VAC forced-air, heat pump, boiler or PTAC systems, checked first with ecobee's compatibility tool
ecobee's top thermostat ships with a room SmartSensor, the Power Extender Kit and a trim plate. The maker's spec sheet covers conventional 2H/2C, heat pumps to 4H/2C, boilers and PTACs on 24 VAC, and rules out line-voltage, millivolt and 0-10VDC systems. Dual-band Wi-Fi, Alexa built in, Siri with an Apple home hub. Read the warranty's installer clause before you fit it yourself.
Listing checked . Confirm the model, included parts and availability before ordering.
Published specifications
- Maker: 24 VAC systems; conventional 2H/2C; heat pump 4H/2C; boilers; PTAC or fan coil to 3 fan speeds
- Maker: not compatible with line voltage (110/220V), millivolt or 0-10VDC systems
- Maker: Power Extender Kit included for homes without a C wire; booklet requires 3 or 4 specific wires
- Maker: dual-band Wi-Fi 2.4GHz and 5GHz, Bluetooth 5.0, 915MHz sensor radio, 4 VA, hardwired
- Maker: 4.09 x 4.09 x 1.02 in; 4-inch 540x540 touchscreen; trim plate and one SmartSensor in the box
- Warranty: 3-year limited; maker's pro sheet advertises 5 years with professional installation
Fit and limits
Strengths
- SmartSensor, Power Extender Kit and trim plate are all included, not add-ons
- Maker publishes a full spec sheet: stages supported, wire terminals, Wi-Fi bands and power draw
- Dual-band Wi-Fi, Alexa built in, Siri with an Apple home hub, Google Assistant and SmartThings
Caveats
- The warranty excludes units not installed by a licensed HVAC contractor, while the listing sells DIY installation
- The Power Extender Kit only works if you have the three or four wires the booklet names
- Listing paperwork is inconsistent: part number EB-STATE6-01 and a user guide warranting a different ecobee model
What arrives, and what ecobee says is in the box
This is ecobee's top thermostat: a 4-inch full-colour touchscreen, 540 by 540 pixels, in a metal body. ecobee's own spec sheet lists the box contents as the thermostat, one SmartSensor with a detachable stand or wall mount, the backplate, wiring diagrams, screws and drywall plugs, the Power Extender Kit, a trim plate (also called an adaptor plate) and a quick start guide. The Amazon Item details list the same components. You do not have to buy the room sensor or the trim plate separately, which is the main thing that separates this model from the cheaper ecobee models on the same shelf.
The thermostat itself is 4.09 inches square and, per ecobee's spec sheet, 1.02 inches deep. The trim plate is larger at 6.29 by 5.65 inches, and it exists to cover paint marks and holes left by the thermostat you are removing. Amazon's table gives the product dimensions as 2.9 inches deep by 4.09 wide by 4.09 high; the maker's 1.02-inch depth is the figure taken from the device drawing, so measure against that and treat Amazon's depth as packaging or listing data.
ecobee's spec sheet also lists the on-board sensors: temperature, humidity, proximity, occupancy and air quality measuring VOC and eCO2. The air quality monitor is the feature ecobee uses to separate this model from the Enhanced, and its output is alerts and suggestions in the app, not a laboratory measurement.
The systems ecobee says it works with, and the ones it does not
ecobee's spec sheet says the Premium works with most 24 VAC HVAC equipment: gas, oil, electric, dual fuel and forced air; conventional systems at two stages of heat and two of cool; heat pumps at four stages of heat and two of cool, meaning a two-stage heat pump plus two stages of auxiliary heat; boilers; and PTACs or fan coil units with up to three fan speeds. It lists 1-wire or 2-wire accessory support for humidifiers, dehumidifiers and ventilators, and names the terminals RC, RH, G, Y1, Y2, C, W1, W2, O/B, ACC+, ACC- and PEK+.
On the unsupported side, the maker is direct. The compatibility panel ecobee runs on the Amazon listing says any of these high voltages is not compatible: line voltage at 110 or 220 volts, millivolt systems and 0-10VDC systems. The installation booklet repeats it as a warning: the thermostat is designed for 24VAC with a 2A maximum current, and you should not connect it to line voltage or millivolt systems. The booklet has a compatibility checkpoint at step 3 that asks you to look for those voltage markings on your old backplate before you go any further.
Amazon's specification table muddies this. Its "Specific Uses For Product" field lists Air Conditioner, Boiler, Dehumidifier, Electric Baseboard Heater, Furnace, Heat Pump and Humidifier. ecobee's own panel on the same page rules out line-voltage systems such as electric baseboard heat. Do not read that field as a compatibility statement. Run your own wires through ecobee's checker at ecobee.com/compatibility/thermostat before you buy, which is what both the listing bullet and the booklet tell you to do.
No C wire? The Power Extender Kit has its own wire requirement
ecobee's spec sheet says the Premium is hardwired and does not need charging or another power source, and that the included Power Extender Kit lets you power it reliably when a C wire is not available. That is the selling point of the PEK, and it is why the listing can call this an easy install in homes without a C wire. The booklet routes you at page 24 into a separate PEK procedure that happens at the HVAC equipment, not at the wall.
The part buyers miss is the checkpoint on the next page. The booklet says the Power Extender Kit requires your system to have either four wires, W/W1, Y/Y1, G and R (or RC or RH), or three wires, Y/Y1, G and R (or RC or RH). If your wall does not have that set, the booklet sends you to ecobee's compatibility checker and support rather than on to the next step. So "no C wire needed" is conditional on which wires you do have.
The PEK install is not a wall job. The booklet has you power down the HVAC system at the breaker, open the equipment cover to reach the control board, photograph and label the R, Y or Y1, G, and W or W1 wires, move them into the PEK's grey terminal blocks, connect the PEK's five white wires back to the matching control-board terminals, and mount the PEK inside the equipment. It carries a warning that HVAC systems contain high-voltage wiring and points to ecobee.com/proinstall if you would rather not do it. It also says that wires on both RC and RH at the control board may mean a two-transformer system, and to call ecobee support before continuing. We are not reproducing the wiring steps here; follow the printed booklet or the app.
Network, voice and the parts that need a subscription
ecobee's spec sheet lists dual-band Wi-Fi, 802.11 b/g/n at 2.4GHz and 802.11 a/n/ac at 5GHz, plus Bluetooth 5.0 and a 915MHz radio for ecobee's own sensors. It gives WEP, WPA and WPA2 encryption, DHCP or static IP addressing, power consumption of 4 VA and an estimated 15MB of bandwidth a month depending on Alexa use. Amazon's table lists connectivity technology as Bluetooth and claims one lithium-ion battery is required and included; the maker describes a hardwired device with no other power source, so read the table field with care.
The maker page says it works with Amazon Alexa, Google Assistant, Apple Home, Samsung SmartThings and ecobee by Generac, and the spec sheet adds Alexa Built-in, Siri enabled with an Apple home hub required, control through iOS and Android apps and on Apple Watch, built-in microphones, a built-in speaker and far-field voice recognition. Nothing we read on ecobee's spec sheet or product page states Matter support for this thermostat, so do not assume it; check ecobee's current support pages if Matter is a requirement for you.
Several headline features are subscription-gated, and the listing says so in small print. The listing's own bullet says the smoke-alarm listening feature requires an ecobee Smart Security subscription, and the spec sheet footnotes both the smoke alarm detection and the security-hub role the same way. The doorbell live view needs an ecobee Smart Doorbell Camera you buy separately. The temperature, sensor and scheduling functions do not need a subscription; the security and monitoring layer does.
Three versions of the warranty appear, and one clause matters
Amazon's Item details give a 3 year manufacturer warranty. ecobee's product page says its devices are covered by a 3-year limited warranty. ecobee's contractor spec sheet for this same model says something different: under "Warranty (Pro install only)" it advertises an industry-leading 5-year warranty, and the sheet's pro-facing summary opens with "5-year warranty with professional installation". The longer term is tied to professional installation, not to the box.
The clause worth reading before you buy is in the warranty text of both PDFs the listing supplies. The 3-year limited warranty lists what it does not apply to, and one of the listed conditions is a product that "was not installed by a licensed Heating Ventilating and Air Conditioning (HVAC) contractor", alongside improper installation. The same listing markets easy DIY installation right out of the box and an industry-leading 3-year warranty in one bullet. Those two statements sit badly together, and we are not going to resolve them for you: if the warranty matters, ask ecobee in writing how it treats a self-installed unit before you fit it yourself.
The rest of the terms are ordinary. The warranty runs from the date of purchase to the consumer, repair or replacement is at ecobee's option, a repaired or replaced device is covered for the rest of the original term or ninety days, whichever is longer, proof of purchase is required, removal and reinstallation costs are not covered, and the warranty is valid only in the country where the product was purchased. Abuse, neglect, electrical fault, accident, acts of nature and unauthorised modification are excluded. Check the seller and the condition of the offer you select, since warranty eligibility follows the original purchase.
What the listing's own documents disagree about
The model identity is not clean. Amazon's Item details give both Model Number and Manufacturer Part Number as EB-STATE6-01. The terminal chart that the listing supplies as its User Manual names three ecobee models by part number, and the Premium appears there as US EBSTATE6P-01 and CAN EB-STATE6PC-01. The six-page user guide the listing supplies carries a warranty that names its product as "the ecobee SmartThermostat with voice control", which is ecobee's earlier model, while the same guide's body describes the built-in air quality sensor that belongs to the Premium. The 29-page installation booklet is dated 2019 and never uses the word Premium at all.
None of that changes what you are buying: the listing title, the A+ content, the included-components list and ecobee's own Premium spec sheet all describe the Smart Thermostat Premium with its SmartSensor, PEK and trim plate. But it does mean the paperwork in the box may not match the model name on the listing, and the part number shown in Amazon's table is not the part number ecobee prints for the Premium. If you need a specific part number for a rebate application or a contractor quote, confirm it against the label on the unit you receive.
One more useful line comes off the terminal chart: it notes that a heat pump configuration supports a dual fuel or hybrid system with 1-stage auxiliary heat, that there is no support for fan-coil pipe sensors, and that powered accessories require an add-in isolation relay. The chart covers three ecobee models in three near-identical tables and does not clearly label which table belongs to which part number, so treat those notes as questions to ask ecobee rather than settled facts about the Premium.
Check the current listing
Confirm the model, included parts and availability before ordering.
Primary sources
- ecobee Smart Thermostat Premium tech specs and sell sheet (maker PDF)
- ecobee product page for Smart Thermostat Premium
- ecobee installation booklet supplied with the Amazon listing
- ecobee terminal-designation chart supplied with the Amazon listing
- ecobee user guide supplied with the Amazon listing
Primary sources checked .
Compare with
- Sensi Smart Thermostat ST55
Conventional or heat pump systems up to two stages, on a 2.4GHz network, in the old thermostat's footprint
- Google Nest Thermostat (Charcoal)
Single-stage 24V systems that need a schedule and app control, not multi-stage equipment
- Mysa Smart Thermostat V2 for Electric Baseboard Heaters (BB.2.0.01.NA-US)
120V or 240V electric baseboard, fan-forced convector and radiant ceiling heat in a standard gang box
- Google Nest Learning Thermostat (4th gen) with Nest Temperature Sensor (2nd gen)
Multi-stage 24V systems run through the Google Home app, in homes with or without a C wire
- ecobee Smart Thermostat Essential (EB-STATE7-01)
Simple single-transformer systems with one stage of cooling, on a 2.4GHz network
Side-by-side pages, this model next to: Sensi Smart Thermostat ST55, Google Nest Thermostat (Charcoal), Mysa Smart Thermostat V2 for Electric Baseboard Heaters (BB.2.0.01.NA-US), Google Nest Learning Thermostat (4th gen) with Nest Temperature Sensor (2nd gen), ecobee Smart Thermostat Essential (EB-STATE7-01).