Yes, you can put a smart thermostat on a heat pump, but only if the thermostat has an O/B reversing valve terminal and stage 2 heat wires, and only if the installer configures it as a heat pump rather than a furnace. Get that wrong and the compressor gets stuck in the wrong mode, the backup electric heat runs far more often than it should, and you can spend a heating season paying bills that make no sense. I have spent 2026 walking through wiring diagrams with our readers, and the single most common mistake is treating a heat pump like an ordinary gas furnace.
That is why this roundup is not just another ranked list of screens and apps. Every pick below is judged against the same heat pump checklist: does it accept an O/B input, does it stage heat up to two stages, can you set an auxiliary heat lockout, does it work on a 24 VAC system, and what happens on your walls when there is no C wire. The specs come from the manufacturer listings and the owner reviews; the compatibility verdicts are mine.
Ten models made the cut, and they run from a straightforward Amazon unit to the ecobee Premium with a room sensor in the box. If you want the broader picture of connected temperature control first, read our guide to the best smart thermostats overall and our picks for thermostats for smart homes, then come back here for the heat pump detail.
One thing to know before you buy anything: a thermostat cannot fix a mechanical problem. If your heat pump short cycles, freezes up or runs backup heat constantly no matter what you set, the issue is refrigerant charge, airflow, duct sizing or a failing reversing valve. A smart box will simply report the problem more accurately than the old dial did. Fix the equipment first.
Top 3 Best Smart Thermostats For Heat Pumps (October 2026)
Google Nest Thermostat
- Learns your schedule
- Works with Matter and Alexa
- ENERGY STAR certified
Amazon Smart Thermostat
- Alexa and Ring control
- Home away sleep schedules
- ENERGY STAR certified
The Nest Thermostat takes the top slot because it does the two things a heat pump needs most without a subscription or an accessory purchase: it learns a schedule that keeps the compressor running long and steady, and it runs on the batteries already in most 24V systems. The Amazon Smart Thermostat is the honest budget answer for anyone who lives entirely inside the Alexa ecosystem. The Sensi ST55 is the one we install most often in older houses because the C wire question simply goes away.
Quick Overview: Every Pick Side by Side
Ten models, all rated for 24 VAC low voltage systems and all listed for heat pump use. Read the heat pump column notes before anything else.
| Product | Specifications | Action |
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| Google Nest Thermostat |
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Check Latest Price |
| Amazon Smart Thermostat |
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| Sensi ST55 |
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 Honeywell Home RTH9600WF |
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 Sensi ST75 |
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 ecobee Smart Thermostat Premium |
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 ecobee Smart Thermostat Enhanced |
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 Google Nest Learning 4th gen |
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 Honeywell Lyric T6 Pro |
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 ecobee Smart Thermostat Essential |
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Check Latest Price |
1. Google Nest Thermostat – the learning default with one heat pump caveat
Google Nest Thermostat – Smart Thermostat for Home – Programmable Wifi Thermostat – Snow
Pros
- Largest review base in this roundup at 29k+
- Learns occupancy patterns without setup
- Works with Google Home
- Alexa and Matter
- HVAC alerts and maintenance reminders
- ENERGY STAR certified
Cons
- Heat pump installs may need a C wire or power accessory
- Swipe ring is awkward for less technical users
- Loses function without internet
- Minimal documentation in the box
I picked this one first for a house I was helping a reader in, where the outdoor unit runs a reversing valve and the old thermostat was a 1980s mercury dial. Google lists heat pump as a specific use for this model, and it works on 24 volts, which is what every residential heat pump control board runs. The learning behaviour is the part that matters on a heat pump: the algorithm settles into long, steady cycles rather than the short cycling you get from a fixed schedule, and long steady cycles are exactly what an outdoor unit wants.
The caveat is real and the manufacturer says so plainly. This Nest is designed to work without a C wire in most homes, but heat pump systems may need a C wire or a power accessory. That single line decides whether your install is ten minutes or a two hour job with an electrician, so check your terminal count before ordering. Our general explainer on precision temperature regulation covers how sensor placement changes accuracy, which matters here too, because the Nest reads air at the wall plate and nowhere else.
What you get is a small polycarbonate disc, 3.31 inches across and about 10 ounces, with an LCD face and the familiar metal ring. On the software side the app is still the cleanest of the mainstream options: Savings Finder suggests schedule changes, Nest Renew shifts usage to lower cost hours, and HVAC monitoring sends alerts when something looks wrong. Matter support means it drops into newer smart home setups without much fuss.
The complaints in the reviews cluster in three places. Documentation in the box is minimal, so most installs end with an hour of online research. The unit degrades when the internet is down, which is a genuine problem for a heat pump in an outage, because the whole point of the system is keeping the house safe. And the ring-based swipe controls frustrate older users, which matters a lot in the Reddit conversations about multi-unit homes, where one relative is often handling the thermostat.
Does it stage and lock out auxiliary heat properly?
Because it treats the system as a heat pump, the Nest gives you stage 2 heat and an auxiliary heat lockout setting, which is what stops electric backup strips from carrying the whole house on a mild afternoon. Set the lockout a few degrees above the temperature where your heat pump loses to resistive heat and the compressor stays in charge far longer. On a dual fuel system, the lockout is the single setting that decides whether you save on gas or burn electricity at 3pm.
Where it falls short is sensors. There is no bundled room sensor with this model, so an upstairs bedroom that runs warm stays warm. Owners installing it downstairs and wondering why the readings differ from the old Honeywell Pro are usually seeing exactly that, and a sensor from a different brand is the usual fix.
Who should skip it?
Skip this Nest if your heat pump is dual fuel with a gas furnace backup and you care about precise staging control, or if your internet service is unreliable. It is also the wrong pick for a cold climate house where you need lockout values you can tune finely across a wide outdoor temperature range, because the menus are shallower than the premium models. In a mild climate with a single stage system, it is an easy recommendation.
2. Amazon Smart Thermostat – a no-fuss schedule for Alexa homes
Amazon Smart Thermostat, Save money and energy, Works with Alexa and Ring, C-wire required
Pros
- Lowest entry cost of the roundup
- Backed by Amazon returns
- Solid Honeywell hardware
- Schedules work with little configuration
Cons
- C wire required so some installs need an adapter
- Basic display with little on screen detail
- Alexa features are less useful outside that ecosystem
- Limited scheduling depth
This is the thermostat I suggest when someone says they do not need crazy features, they just want to change the temperature from their phone. It runs on the same hardware family Honeywell uses, which tells you something about the build, and the app setup walks you through the wiring with support available if you get stuck. The heat pump note on the listing is a warning rather than a promise, so verify your system before purchase.
For a heat pump, the useful parts are scheduling and comfort zones. Home, away and sleep schedules cover most households on their own, and comfort zones use select Alexa devices for presence detection so the temperature drops when the last person leaves. The thermostat also emails you details on local rebates after purchase, which is a nice touch in states where utility programs are generous but poorly advertised.
On the savings side the listing quotes the ENERGY STAR estimate of about 90 dollars a year on heating and cooling, which is a marketing figure rather than a promise. Our rule for the buying guide is the same one we use in the smart thermostat energy savings guide: judge savings against what you are replacing, not against the sticker claim.
Reviews praise the price to feature ratio and the painless app setup. They also note the plain display and the fact that the feature set is smaller than what ecobee or Nest offer. If your household is not an Alexa household, several of the headline features quietly stop mattering, and you are paying for a schedule you could set in ten seconds.
Is the C wire going to be a problem in your house?
A C wire is required here, and that is the whole installation question. If your existing control board has a common terminal, this is a straightforward swap. If it does not, you are looking at running a new wire, adding a power adapter at the board, or choosing a different model. The reviews on this product are honest that some installations need an adapter, so budget for that possibility rather than the clean swap.
From a heat pump standpoint, the limitation is depth rather than capability. Auxiliary heat configuration on a dual fuel system is where the money is, and this unit gives you far fewer levers than the Sensi or Honeywell options below. If your system is a simple single stage heat pump with no backup, that limitation rarely comes up.
Who should skip it?
Skip it if you care about humidity control in a humid climate, since the display gives you almost nothing to read at a glance. Skip it if you want remote room sensors, or if you are replacing an old Honeywell Pro and want the interface to feel familiar. It is a poor match for anyone who wants detailed energy reports, and a good match for a rental unit or a secondary space where the thermostat just needs to hold a number.
3. Sensi ST55 – the easiest retrofit when there is no C wire
Pros
- Often installs in about 10 minutes
- C wire not required in most applications
- Scheduling app is the most flexible in class
- Heat pump listed among specific uses
- Sensi does not sell personal data
Cons
- No color touchscreen or voice assistant
- No bundled room sensor
- Geofencing is less refined than premium models
Of everything in this roundup, the ST55 solves the problem that blocks most heat pump thermostat swaps. The common wire is not required in most applications, and the unit ships with two AA batteries, so in a 1980s or 1990s house you can usually mount it, label the wires and be running inside an afternoon. There is a built in level on the body, which sounds trivial until you are trying to get a plate flush on an uneven wall.
The app is the reason this model keeps showing up in our recommendations. It supports independent per day schedules plus multiple schedule templates, which is close to essential for shift workers, and it adds usage reports, equipment alerts and filter reminders without any subscription. On a heat pump, those alerts are worth more than they are on a furnace, because a system that is quietly stuck in backup heat does not announce itself.
Sensi also states plainly that it will not sell your personal information to third parties. In a category where connected devices are permanently attached to your occupancy patterns, that written policy is a genuine differentiator rather than a marketing line, and privacy comes up repeatedly in owner discussions about these devices.
Fit and finish are the trade off. This is a button and display thermostat in a traditional footprint, 5.88 inches wide with an LED readout, and it will look like the unit it replaced. The design is dated next to the Sensi ST75, and there is no speaker, no touchscreen and no included room sensor. The reviews are unusually consistent about that: owners like the app and the install, and they stop there.
What it takes to run a heat pump on this thermostat?
Heat pump is listed among the specific uses, and the ST55 handles multi stage heating, which is what you want when your outdoor unit has a second stage compressor or when a gas furnace is carrying the top stage in a dual fuel setup. During setup you choose system type, and picking heat pump rather than furnace is the step that tells the thermostat to use the reversing valve and to respect the balance point.
The one thing you will not get is fine grained control over auxiliary heat lockout values at specific outdoor temperatures. You can set a lockout, but you cannot build the kind of table a contractor would use. For most households that is a rounding error, and for a cold climate house with electric backup it is not.
Who should skip it?
Skip it if anyone in the house will struggle with a physical button interface, or if you want the temperature visible from across the room. The plain design also means you will be checking your phone to confirm a change, which defeats the purpose for people who like a glanceable display. Choose the ST55 when the wiring is old, the schedule matters, and the budget is real.
4. Honeywell Home RTH9600WF – the color screen heat pump owners read at a glance
Honeywell Home RTH9600WF Smart Color Thermostat ENERGY STAR Wi-Fi Programmable Touchscreen Alexa Ready – C-Wire Required
Pros
- Customizable color display at this tier
- Shows indoor outdoor humidity and forecast
- Works with Alexa and Google Assistant
- Rebate finder built into the app
- Broad forced air and steam support
Cons
- C wire required with finicky setup
- App and menus feel dated
- No included room sensor
- Not for 120 to 240V baseboard heat
Humidity is where this Honeywell earns its place in a heat pump list. It lists heat pumps with electric backup as a supported use, and the home screen shows indoor and outdoor temperature, humidity and a daily forecast. On a system running in the southeast or the Gulf Coast, where latent load drives a large share of your bill, seeing the numbers rather than guessing them changes how you set the schedule.
It also handles the equipment breadth that older homes have. Forced air gas, oil and electric, hot water and steam, and heat pumps with electric backup are all called out, and the app supports Alexa, Google Assistant, IFTTT, Android and iOS. The color screen is customizable, which sounds cosmetic until you have a thermostat mounted at eye level in a bright hallway.
There is also a rebate finder and incentive enrollment support in the app, which is the least glamorous feature on this list and one of the most useful in a cold January. Utility rebates for smart thermostats often cover a meaningful share of the device, and the Amazon Smart Thermostat is not the only model here that will point you at them. Check eligibility before you assume the program excludes your model.
Reviews like the display, the weather data and the broad compatibility, and they push back on three things. The C wire is required, and setup can be finicky without clear documentation. The app and menu structure feel dated next to Sensi or ecobee. And there is no room sensor, so hot and cold spots stay exactly where they were.
Is it the right controller for a heat pump with electric backup?
Yes, and that is the specific use the manufacturer lists. When your heat pump drops out below the balance point and the backup strips take over, this thermostat can hold a lockout so the transition happens where the equipment vendor intended rather than whenever the house feels a little cool. On a system with electric auxiliary heat, that setting is where real money is made or lost.
One caution for very old or very high tech systems. It is not compatible with 120 to 240V electric baseboard heat, and on a communicating or variable speed system you may lose equipment specific features that only the factory controller speaks. Ask your contractor whether your indoor unit needs its own board.
Who should skip it?
Skip it if you want a modern app, because reviewers consistently describe the software as a generation behind. Skip it if the wiring is marginal, because the C wire requirement plus the setup notes make for a frustrating first afternoon. It is a strong choice for a humid home on a heat pump with electric backup where the person living there wants humidity data on the wall, and a weak choice for someone who lives in their phone.
5. Sensi ST75 – the highest rated screen in the roundup
Pros
- Highest average rating here at 4.5 stars
- Large color touchscreen with intuitive menus
- Illuminated easy click terminals and built in level
- Keeps the Sensi flexible scheduling and geofencing
- Sensi does not sell personal data
Cons
- C wire required unlike the ST55
- No built in speaker or voice assistant
- Sensors and eco features trail the ecobee models
The ST75 is the model I recommend when someone wants the simple button layout gone but does not want to pay for a smart speaker or a subscription. A 4.3 inch color LCD, a plastic body that weighs 13.6 ounces, and the same app the ST55 owners already praise. On a heat pump, the difference from the entry model is really about the interface, not about equipment control.
That distinction matters for a specific reason. Adjusting auxiliary heat lockout on a heat pump means visiting menus, and doing that on a small monochrome readout is miserable. The color screen with clear menus turns a configuration chore into a two minute job, and on a heat pump the configuration is where the savings actually live.
Installation is friendlier than the rating suggests because the terminals are illuminated and there is a built in level, though the C wire is required. Heat pump is listed among the specific uses, and the C wire requirement is often already satisfied on a heat pump system because many of them were installed with a common wire for the outdoor unit and defrost controls.
Reviews center on the touchscreen, the straightforward wiring and the app, and this holds the highest average rating of any product we analyzed, with 77 percent five star reviews. The named drawbacks are the C wire requirement compared with the ST55, the absence of a voice assistant, and room sensors being a separate purchase with a separate price.
What you give up versus the ecobee options?
You give up the sensors and the speaker. Ecobee units in this roundup include or support a SmartSensor for room by room comfort, and the Premium adds a smart speaker with Siri or Alexa, an air quality monitor and a doorbell camera option. The ST75 has none of that. It reads temperature at the wall plate and reports what it reads.
For a heat pump owner in a two storey house, that limitation is about comfort, not efficiency. The compressor still runs the same way. If your complaint is a warm upstairs bedroom, you need sensors or a second zone. If your complaint is the electric bill, this screen is more than enough.
Who should skip it?
Skip it if you want a thermostat that can make calls to your heating system without touching a phone, or if you are starting from scratch and want sensors included. It is also a poor fit for a house with no C wire, where the ST55 is the same app for less money. Choose the ST75 when the wiring is good, the household wants a screen they can read, and the schedule is complex.
6. ecobee Smart Thermostat Premium – room sensors in the box
ecobee Smart Thermostat Premium – WiFi, Siri & Alexa Built-In, Smart Sensor
Pros
- Room sensor included so balance works out of the box
- Highest compatibility claim here at 95 percent
- Radar occupancy sensing preheats and precools
- Air quality alerts and filter reminders
- Siri and Alexa built in
Cons
- Highest cost in the roundup
- Additional SmartSensors cost extra
- Siri needs an Apple home hub
- Heavy metal body needs solid mounting
This is the only model here that ships with a remote room sensor, and for a heat pump home with uneven temperatures that is the feature that earns its place. The SmartSensor detects which rooms you actually use and moves the target temperature there, which shortens the run time of the outdoor unit while making the rooms you care about more comfortable. Nothing else in the list does that without a second purchase.
The Power Extender Kit is also included, along with a trim plate, so in most homes without a C wire you avoid the adapter purchase that the other ecobee models leave to you. Compatibility is claimed at 95 percent of HVAC systems, the highest figure in this roundup, and the listed uses cover heat pumps, furnaces, boilers, baseboard heaters, humidifiers and dehumidifiers.
There is a metal body, roughly 1.3 pounds, which is heavier than everything else on this list and needs a solid mounting position. The built in radar occupancy detection preheats and precools so the house is comfortable when you arrive rather than ten minutes later, and the air quality monitor produces alerts, improvement tips and filter reminders that are genuinely useful on a heat pump running long shoulder seasons.
The built in speaker runs Siri or Alexa and can stream Spotify or listen for smoke alarms, and it can two way talk through an ecobee smart doorbell camera. That is a lot of hardware in one wall box, and reviewers who bought it for the sensor frequently note that they never touch the speaker, which is fine, because the sensor is the reason to buy it.
How it behaves on a heat pump with backup heat?
Like the other ecobee models, it treats the system as a heat pump and lets you set an auxiliary heat lockout so the compressor carries the load until it genuinely cannot. The SmartSensor also changes that calculus slightly, because the sensor averaged temperature can delay the call for backup heat that the wall plate would have triggered sooner, which usually saves money and occasionally annoys someone.
Two cautions. Additional SmartSensors are sold separately, so a four bedroom house needs a plan and a budget. And some smart security features sit behind a subscription, which is worth checking before you commit.
Who should skip it?
Skip it for a single zone home where the wall plate temperature matches the rest of the house, because you would be paying for a sensor that has nothing to balance. It is also a poor match for a household that does not want a microphone in the living room, and for anyone who finds the installation too heavy to be comfortable on their own. For a two storey or three storey heat pump home with real temperature swings, it is the most complete answer on this list.
7. ecobee Smart Thermostat Enhanced – occupancy automation without the speaker
Pros
- Occupancy sensing and eco+ deliver real efficiency gains
- PEK included so no C wire purchase needed
- Widest ecosystem support including Apple Watch
- Metal build feels more premium than plastic rivals
- Free app upgrades and 3 year warranty
Cons
- No SmartSensor in the box
- Less capable than the Premium at a similar spend
- No smart speaker or air quality sensor
Everything about this model is aimed at the same target as the Premium, minus the parts most people never use. Occupancy sensing detects when the house is empty and adjusts, eco+ uses routine, weather and grid activity to improve efficiency, and the Power Extender Kit plus trim kit are in the box. Compatibility is claimed at 90 percent of HVAC systems, and heat pumps, furnaces, boilers and humidifiers are all listed uses.
On a heat pump this is the most automation forward option without a sensor. The system learns temperature preferences and schedule, and it adjusts for humidity, which is the behavior that keeps a heat pump from overshooting in shoulder season. If you have a predictable morning routine, the occupancy features do more for your compressor hours than a fancier screen would.
Build quality is a step above the plastic competitors, with a metal body and a 4 inch display, and it works with Alexa, Google Assistant, Apple HomeKit and SmartThings, with remote control from an Apple Watch. The 3 year warranty is the longest offered by the brands in this roundup alongside the other ecobee models and the Sensi units.
The honest weakness is the comparison shoppers keep making. It is less capable than the Premium while sitting at a similar spending level, and the SmartSensor is not included, so the room balancing that justifies the Premium is a second purchase here. The most common owner caveat is exactly that, and the second most common is that some smart security functions need a subscription.
Is it compatible with your heat pump setup?
Run the ecobee compatibility checker before you buy, because the 90 percent figure is an aggregate across every equipment type, not a promise about your particular board. In practice the models that fail are unusual staging arrangements and some older or proprietary systems. A dual fuel system with two heat stages is routine, and a communicating or variable speed system is where you should ask your contractor first.
Because the PEK is included, the wiring side is easy. You mount the trim plate, adapt the power at the control board, and the app walks through terminal identification. Give yourself an afternoon and label the wires before you start.
Who should skip it?
Skip it if the room sensor is the whole point, or if you were drawn to the Premium for the speaker and air quality monitor, since neither is here. It is also a strange buy for a house with balanced rooms, because occupancy automation is the feature doing the work. Choose it when you want a thermostat that quietly adapts to a heat pump with no schedule management, and you would rather not think about it.
8. Google Nest Learning Thermostat 4th gen – the bundled sensor changes the picture
Google Nest Learning Thermostat (4th gen) + Nest Temperature Sensor (2nd gen) – Obsidian
Pros
- Temperature sensor included for hot and cold rooms
- 60 percent larger display readable across the room
- Adaptive Eco recovers within an hour
- Works with most 24V systems including heat pumps
- Build quality with a precise dial
Cons
- High cost for the category
- Depends fully on the Google Home app and cloud
- Learning schedule changes can surprise users
- Limited support outside US and EU systems
The fourth generation fixes the two complaints that used to matter most from Nest owners, and both fixes matter on a heat pump. The first is the bundled Nest Temperature Sensor, which lets the thermostat average or prioritize a room instead of trusting a hallway wall plate. The second is compatibility, since it works with most 24V systems including gas, electric, oil, forced air, heat pump and radiant, and a C wire is not required in most homes.
Adaptive Eco uses outdoor temperature to find an efficient away setting and recovers within an hour, and the system learns how outdoor conditions affect indoor temperature and pauses when it can. On a heat pump that pause behavior is worth real money, since an outdoor unit that is not asked to run during a mild afternoon is an outdoor unit you are not paying to maintain.
The display is 60 percent larger than the previous generation with Dynamic Farsight and automatic brightness adjustment, and the body is aluminium rather than polycarbonate. It works with Alexa, Siri, Google Assistant, HomeKit and Matter. Reviewers single out the display and build as the reasons this generation feels like a step up, and 78 percent of reviews are five star.
The reservations are about ecosystem dependence and money. The unit depends on the Google Home app and cloud connectivity, so an outage means no control. It asks permission before making schedule changes rather than editing silently, and some users read that as the thermostat second guessing them. It also costs more than every other model here except the ecobee Premium, and extra sensors add to that.
What the bundled sensor changes for a heat pump home?
It changes where the thermostat thinks your house is. With a sensor in the bedroom, the system targets the temperature you actually want in the room you actually use, which usually means a slightly lower setpoint for the same comfort level. Lower average setpoint in shoulder season means the compressor runs within a narrower band, and a heat pump is most efficient when it is not being asked to heat a hallway to 72.
It also gives you the closest thing to room prioritization in this roundup. The thermostat will use the sensor reading rather than the wall plate for the call, and you can place the sensor in the room that runs cold. What it will not do is send more air to that room, which is the limit owner after owner mentions in the forums about unbalanced systems.
Who should skip it?
Skip it if you are outside the US and EU heating markets, since compatibility without extra hardware is limited. Skip it if the cloud dependence worries you, or if the cost is the deciding factor, because no other model here combines a bundled sensor with this build quality at a lower spend. It is a strong fit for a heat pump household that wants minimal involvement and has rooms worth watching.
9. Honeywell Lyric T6 Pro – built for two heat and one cool heat pumps
Honeywell TH6220WF2006/U Lyric T6 Pro Wi-Fi Programmable Thermostat with Stages Up to 2 Heat/1 Cool Heat Pump or 2 Heat/2 Cool Conventional
Pros
- Explicitly rated for two stage heat pumps
- Proven long running Honeywell platform
- Good value for a Wi-Fi programmable
- Solid 4.4 star average across a large review base
Cons
- Dated hardware and app by current standards
- No touchscreen or room sensors
- Little detail in the listing about accessories
This is the most technically specific pick in the roundup. The Lyric T6 Pro is specified for heat pump systems up to two heat and one cool stage, and for conventional systems up to two heat and two cool. If your outdoor unit has a second stage compressor, or your dual fuel setup has a furnace top stage, this is the model whose manual was written for your equipment.
It runs on two AA batteries with Wi-Fi programming, app and voice control, and it is ENERGY STAR certified. At four ounces and 5 by 2.3 by 6 inches it is the smallest and lightest controller on this list, which matters if you are mounting it on a thin wall or in an older plaster house where a large plate needs care.
Buyers rely on it for dependable multi stage heat pump control and report stable scheduling, with 74 percent five star reviews. The dated styling and app compared with the T5 and newer T series come up often, and so does the lack of any touchscreen, sensor or voice assistant. For a controller that lives in a hallway, none of that matters as much as the stage handling does.
One practical note from the listing itself. This model has been available since December 2016, so the hardware is proven and the firmware is settled, but the app experience reflects its age. If you plan to live in your phone for thermostat control, test the app in the store or on a reviewer’s account before committing.
Why two stage support is the feature that matters?
Stage 2 on a heat pump exists because the first stage cannot always keep up on a cold morning. A thermostat that can call the second stage, and lock out the electric backup until the second stage is already working, is what keeps your compressor from short cycling and your strips from running as the first response to every call.
Most general purpose thermostats in this roundup can stage two heat. The difference here is that the manufacturer documents the heat pump limit explicitly, two heat and one cool, which is the correct specification for a heat pump rather than a mistake. On a dual fuel system the same model handles two heat and two cool, so one controller covers both equipment types.
Who should skip it?
Skip it if you want room sensors, a color screen, or an app that feels current. Skip it if you plan to add a smart speaker, since there is no voice assistant beyond the usual ecosystem integrations. It suits a household that wants a proven controller for a specific multi stage heat pump, and does not want to fiddle with anything after install.
10. ecobee Smart Thermostat Essential – the budget door into the ecobee app
Pros
- Entry point to the ecobee app and ecosystem
- Color touchscreen at a modest spend
- eco+ adds humidity detection and schedule assistant
- Free software upgrades extend the value
- Works with HomeKit
- Google Assistant and Alexa
Cons
- Power Extender Kit and SmartSensors cost extra
- Lowest compatibility figure in the ecobee range
- Lowest rating in the roundup at 4.2 stars
The Essential is the way into the ecobee app without paying for the metal bodies and the sensor. You get a 3.74 inch color touchscreen, app control with free software upgrades, and the eco+ feature set, which includes indoor humidity detection, a schedule assistant and time of use preheat and precool. That humidity detection is more useful on a heat pump than on a furnace, since a system that is over cooling to strip moisture is doing exactly what the setting is meant to support.
Compatibility is claimed at 85 percent of systems, the lowest of the three ecobee models here, and the listed hardware coverage is wide: gas, oil, electric, dual fuel, forced air, heat pumps with two heat and one cool, and boilers. Run the online compatibility checker first, and if your system is anything unusual, ask your contractor before ordering.
The Power Extender Kit and trim kit are not included, so a house without a C wire has an extra step. That is the single biggest reason the higher ecobee models exist, and it is worth pricing before you decide this is the cheaper route. The body is plastic, 3.2 ounces, with a matte white face that looks closer to a traditional thermostat than the black metal units.
Owners treat it as good value and like the touchscreen plus eco+ scheduling. Complaints concentrate on accessories having to be purchased separately and on occasional compatibility questions in less common HVAC setups. It holds the lowest average rating in this roundup at 4.2 stars, with 68 percent of reviews still at five stars, which reads as a solid budget product rather than a problem.
When this model makes more sense than the ecobee above it?
It makes sense when you have a C wire, one zone, and no interest in sensors or speakers. In that case the extras on the Premium and the Enhanced are dead weight, and this touchscreen with eco+ scheduling covers everything a heat pump needs day to day. The savings claims referenced in the listing compare against holding 72F, which is a reasonable benchmark to keep in mind.
It makes less sense if the plan is to add SmartSensors later, because you are buying the thermostat twice. Add the sensor cost to the Premium and the math changes quickly in a house with real temperature swings between floors.
Who should skip it?
Skip it without a C wire unless you are willing to buy the extender kit, and skip it if your installer needs a wide compatibility margin. It is a weak fit for a cold climate heat pump where you want a finely tuned lockout table, and a poor second choice for a house that will later need room sensors. It is a good fit for a first smart thermostat in a straightforward single system home.
How to Choose a Smart Thermostat for a Heat Pump?
Start with the terminals on your control board, not with the screen. A heat pump system needs R for 24 VAC power, W for heat, Y for cooling, G for the indoor fan, C for the common power wire, and O/B for the reversing valve that switches the outdoor unit between heating and cooling. A two stage heat pump adds W2, and a system with electric backup heat adds AUX or E. If your new thermostat has no O/B terminal, it is not a heat pump thermostat, whatever the box says.
Next, decide how many heat stages your system has. Most residential heat pumps are single stage, some are two stage, and dual fuel systems add a gas furnace stage on top. A thermostat rated for two heat and one cool handles the common case, and the Honeywell Lyric T6 Pro documents that limit explicitly.
Then think about power. A C wire supplies constant 24 VAC so the thermostat can drive relays, run a color screen and keep the outdoor unit and indoor fan communicating. A power stealing design can limp along, but on a heat pump with stage 2 and a reversing valve, we would not trust it. Several models here ship a power extender kit that adapts power at the control board instead, which is a good middle path.
After that, match the interface to the household. People who will genuinely use a schedule benefit from a good app, and the Sensi app is the one we see praised most often for independent per day schedules. People who want the house to behave without them prefer occupancy sensing, which is what the ecobee Enhanced and Premium do well. People who want a familiar box with buttons are better served by the Honeywell and Sensi models that keep the traditional layout.
Sensors are the last decision, and the one most people get wrong. A remote sensor tells the thermostat what a room feels like. It does not send more air to that room. If your upstairs is cold because the ductwork is undersized or the static pressure is high, no thermostat in this roundup fixes that, and owners say so repeatedly in the forums. Sensors solve comfort reporting, not airflow.
Finally, check the ecosystem and the privacy terms. Sensi states it will not sell personal information to third parties, which is a difference worth weighing against devices with voice assistants that are always listening. If your home already runs on one platform, staying inside it reduces friction far more than any single feature on the spec sheet.
Do You Need a C-Wire for a Heat Pump Thermostat?
Not always, but heat pumps make it more likely than furnaces do. A smart thermostat needs a reliable power source, and the C wire is the clean one. Many heat pump installations from the last 25 years include a common wire because the outdoor unit and the defrost logic need constant power, so check before you assume the worst.
Count the wires at the current thermostat, not at the furnace. If you see a bundle that includes a blue or black wire going into a C terminal, you have a common wire and can move on. If you see only red, white, yellow and green, keep reading.
You have three options when the C wire is missing. First, run a new wire, which is the most correct answer and usually a short run through an attic or basement. Second, install a power extender kit at the equipment, which adapts power from the heating circuit and is the right call when the walls are finished and you do not want to open them. Third, use a power stealing design, which we do not recommend on a heat pump with stage 2, a reversing valve and a color screen, because the load is too heavy and the failure mode is a dead display in January.
On a heat pump specifically, check the manufacturer’s requirement before assuming power stealing will be fine. The Nest listing itself warns that heat pump systems may need a C wire or a power accessory, which is a plain statement that the usual exemptions do not always apply.
If your wiring is unidentified, if you have a zoning panel, if your equipment is communicating or variable speed, or if you cannot get reliable power at the board, stop and call an HVAC contractor. The cost of a service call is trivial compared with a failed control board, and contractors can also confirm whether your indoor unit needs its own factory controller.
Auxiliary Heat Lockout, the Balance Point, and What You Will Actually Save
The balance point is the outdoor temperature where your heat pump can no longer deliver enough heat to keep up with the house. Below it, the backup heat has to run whether you like it or not. Above it, the compressor is doing the work at a fraction of the cost per hour. A thermostat cannot change the balance point, but it decides when the system gives up on the compressor, and that decision is worth more on a heat pump than on any other system.
Auxiliary heat lockout is the setting that controls it. Raise the lockout temperature and the compressor is asked to work harder for longer before the backup strips or the gas furnace kicks in. Lower it and you get a warm house with a bigger bill. For a heat pump with electric auxiliary heat, moving the lockout up a few degrees is often the single largest controllable saving available to you, and it is free.
Set the lockout, then let the thermostat run for two weeks before changing anything else. Owners who adjust the schedule, the lockout, the sensor placement and the setback in the same weekend never learn which change worked. Our heat pump buying guide covers the same discipline on the equipment side, and the same logic applies to the controller.
On savings, be realistic about where you started. Replacing a manual dial thermostat with any ENERGY STAR model commonly produces a 10 to 15 percent reduction. Replacing a programmable thermostat that was working fine and that you ignored produces closer to 3 to 7 percent. Replacing an old smart thermostat that already schedules for you produces very little, sometimes nothing. Marketing figures such as 23 or 26 percent are upper bounds computed against a 72F hold, not field averages.
The honest framing is that a smart thermostat on a heat pump is mostly an efficiency tool for the shoulder season and the hours nobody is home. The equipment is what carries you through a cold snap, and no thermostat setting changes the cost of that stretch. A variable compressor on a well sized system already outperforms almost anything the thermostat can do, which is why we would rather see you spend effort on sizing and ductwork than on another app.
Frequently Asked Questions
Can you put a smart thermostat on a heat pump?
Yes, as long as the thermostat has an O/B reversing valve terminal and stage 2 heat wires. Set the system type to heat pump during setup so the reversing valve and the balance point are handled correctly. A mismatch can leave the compressor in the wrong mode or run backup heat far more often than it should.
Do I need a C-wire to install a smart thermostat?
Usually, yes. The C wire provides constant 24 VAC power for the display and the relays. If it is missing, you can run a new wire, install a power extender kit at the equipment, or use a power stealing design. On a heat pump with stage 2, we recommend the extender kit over power stealing.
Will a smart thermostat save money with a heat pump?
Sometimes. Moving from a manual dial to an ENERGY STAR model commonly yields 10 to 15 percent. Moving from a working programmable thermostat you already used well yields about 3 to 7 percent. The larger win on a heat pump is setting auxiliary heat lockout so the compressor carries the load above the balance point.
Is ecobee or Nest better for a heat pump?
It depends on the room. Nest wins for a simple single system with a schedule you set once, and the fourth generation bundles a temperature sensor. ecobee wins for uneven temperatures because sensors and occupancy sensing are central, and the Premium includes a sensor and a power extender kit.
Is Sensi better than Honeywell?
Sensi wins on installation flexibility, since the ST55 usually runs without a C wire and both models share a flexible scheduling app. Honeywell wins on hardware breadth and on documenting heat pump stage support, with the Lyric T6 Pro specified for two heat and one cool systems.
Why do HVAC contractors push back on popular smart thermostats?
Because of installation, not brand. Contractors worry about identifying wires correctly, losing factory features on communicating equipment, and being called back when a cloud dependent device has no schedule after an outage. A thermostat chosen for its heat pump terminals and stage support makes their job easier.
How do I set auxiliary heat lockout on my thermostat?
Enter installer settings, choose system type, and find the auxiliary heat lockout value. Set it a few degrees above the outdoor temperature where your heat pump stops keeping up, then run the system for two weeks before changing it again. On a dual fuel system, raise it until the gas furnace stops carrying mild afternoons.
Do room sensors make a heat pump home more efficient?
No. A sensor tells the thermostat what a room feels like, but it cannot send more air there. Sensors improve comfort and can let you lower the average setpoint slightly, which helps. If a room is cold because of duct sizing or static pressure, that is an equipment problem and needs a contractor.
The Verdict
The best smart thermostats for heat pumps in 2026 come down to what your wiring and your house actually look like. The Nest Thermostat is the default for a single system with a straightforward schedule. The Sensi ST55 is the answer for older wiring with no common wire. The ecobee Premium is the one to buy when floors run at different temperatures. The Honeywell Lyric T6 Pro is the correct choice for a documented two stage heat pump, and the Sensi ST75 is the best screen you can get without a speaker or a sensor.
Check your terminals, set the system type to heat pump, and tune the auxiliary heat lockout before you change anything else. If any of that is unclear, an HVAC contractor visit is cheaper than a season of bad bills.
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