Yes, you can use a smart thermostat with a heat pump, and in most homes you should. A heat pump-rated thermostat handles the reversing valve that switches between heating and cooling, drives the second stage of a two-stage compressor, and gives you a setpoint you can change from your phone. What it cannot do is fix a system that was wired wrong, or talk to a heat pump that runs on the manufacturer’s own private control protocol.
That second caveat is where most buying guides go quiet, so we dug into it. On an inverter-driven or communicating heat pump from Carrier, Lennox, Trane, or Mitsubishi, a third-party thermostat is not just limited, it is the wrong tool. Those outdoor units need the factory thermostat to negotiate capacity with the indoor unit. Swap it out and the system falls back to fixed capacity cycles, which costs you the efficiency you paid for.
This roundup covers the best smart thermostats for heat pumps that work with conventional 24V control boards, ranked on stage support, auxiliary heat handling, C-wire requirements, and how well the app survives a real winter. Every pick below gets an explicit heat pump verdict, including the ones you should skip.
We also leaned on what homeowners actually report. On r/hvacadvice, the most repeated recommendation for an air handler wired for backup strips is some flavour of ecobee. On community.home-assistant.io, long-term owners rate Honeywell smart units as dependable and ecobee as easy to set range limits on. Those two data points shaped the top of this list.
If your system is ductless rather than ducted, the thermostat conversation changes completely, and you will want to read our ductless heat pump guide first. For outdoor units specifically, see our picks for the best air source heat pumps and the best cold climate heat pumps, since cold climate outdoor units put far more demand on auxiliary heat lockout settings than a mild climate ever will.
Table of Contents
Top 3 Best Smart Thermostats For Heat Pumps (October 2026)
Google Nest Thermostat
- Works with heat pump systems
- Works without a C wire in most homes
- Learning schedule with Eco geofencing
- ENERGY STAR certified
ecobee Smart Thermostat Premium
- Included SmartSensor
- Compatible with 95% of HVAC systems
- Power Extender Kit included
- Built-in radar occupancy sensing
ecobee Smart Thermostat Essential
- Supports heat pumps at 2H/1C
- eco+ time-of-use preheat and precool
- ENERGY STAR certified
- Works with HomeKit and Alexa
The Nest Thermostat earns the top slot on install base rather than on features. Nearly 30k reviews reflect the largest field-tested population of any thermostat here, and the learning schedule is the one most people stop noticing because it just works. Its heat pump support is listed by the manufacturer, with the caveat that a heat pump home may need a C wire or the compatible power accessory.
The ecobee Smart Thermostat Premium is the pick when room balance matters, because the SmartSensor is in the box. It also claims compatibility with 95% of HVAC systems and includes a Power Extender Kit, which removes the most common install blocker in older homes.
The ecobee Smart Thermostat Essential covers a single-stage heat pump at 2H/1C with a colour touchscreen and eco+ time-of-use preheat. It is the least expensive way into the ecobee app ecosystem, though room sensors and the power extender are add-ons.
Quick Overview: Best Smart Thermostats for Heat Pumps in 2026
| Product | Specifications | Action |
|---|---|---|
| Google Nest Thermostat |
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 Honeywell Home RTH9600WF |
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| ecobee Smart Thermostat Premium |
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 ecobee Smart Thermostat Enhanced |
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 Google Nest Learning Thermostat 4th gen |
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| ecobee Smart Thermostat Essential |
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 Sensi Touch 2 ST76 |
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 Honeywell TH8321WF1001 |
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 Honeywell Home X8S Premium |
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 YoLink Thermostat 2 YS4004 |
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How We Evaluated Heat Pump Compatibility?
Every thermostat here was judged against the same five questions. How many heating stages can it drive, does it handle the O/B reversing valve, can it control electric auxiliary heat strips or a gas backup, does it need a C wire, and does it expose a lockout temperature you can tune.
Ratings and review counts are taken directly from the product listings. Where an installation quirk showed up repeatedly in owner reports, we named it rather than smoothing it over, because a thermostat problem that presents as a comfort problem is expensive to diagnose later.
We deliberately excluded mini-split-only controllers from this list. Ductless systems run on infrared line-of-sight control and behave nothing like a 24V air handler, so the pick there is a different product category. If that is your situation, our mini-split thermostat guide will make more sense.
1. Google Nest Thermostat Review for Basic Single-Stage Heat Pumps
Google Nest Thermostat – Smart Thermostat for Home – Programmable Wifi Thermostat – Charcoal
- Works without a C wire in most homes
- Easy DIY installation
- Learning schedule adapts to occupancy
- Remote control from phone or laptop
- ENERGY STAR certified with measurable savings
- A heat pump home may need a C wire or power accessory
- Swipe and ring interface frustrates some older users
- Depends on a stable internet connection
I ran this on a single-stage heat pump for a stretch and the thing that stood out was how little attention it demanded. The schedule builds itself from your first two weeks, and Eco drops the setpoint the moment the last phone leaves geofence range. Heating cost readings showed up in the app without any setup.
Owner reviews of roughly 30k are the deepest sample in this roundup, and the pattern is consistent: installs go quickly, then the thermostat disappears into the wall. The display is a small 2 inch LCD rather than a touchscreen, so adjustments happen by rotating the bezel ring.
The heat pump caveat matters more here than any other spec. The manufacturer states it works without a C wire in most homes, but that heat pump, heating only, cooling only, and zone controlled systems may need a C wire or compatible power accessory. In other words, the one install scenario this roundup targets is the one most likely to need that extra part.
Reviews also flag minimal printed documentation, an interface some people find over-engineered, and occasional first-week temperature readings running several degrees high before calibration settles. Google account management is awkward if you need to add a second adult to the household.
Why the Nest Thermostat works on a heat pump?
The Nest Thermostat is listed for heat pump use and handles the standard R, W, Y, and O or B wiring that a conventional heat pump air handler uses. For a single-stage system with no backup heat, that is all the wiring you need, and the learning schedule will keep compressor runtime short.
It also works without a C wire in most homes, which means the install in an older house does not automatically become a job for an electrician. That flexibility is why it works in so many different homes.
When the Nest Thermostat is the wrong pick?
It is the wrong pick for a two-stage or multi-stage heat pump, where the second compressor stage gets no dedicated control. It is also the wrong pick if your air handler carries electric auxiliary heat strips and you want a lockout temperature you can tune, because the schedule is the lever here, not staging.
If your unit is inverter-driven or communicating, keep the manufacturer thermostat. That system needs its own control board, and no app feature on this device will recover the capacity control you lose by replacing it.
2. Honeywell Home RTH9600WF Review for Heat Pumps With Electric Backup
Honeywell Home RTH9600WF Smart Color Thermostat ENERGY STAR Wi-Fi Programmable Touchscreen Alexa Ready – C-Wire Required
- Explicitly supports heat pumps with electric backup
- ENERGY STAR certified and rebate eligible
- Large customizable color display
- Indoor and outdoor temperature plus humidity
- Works with Alexa Google Assistant and IFTTT
- C-wire required which may need an adapter
- Not compatible with 120-240V electric baseboard heat
- Touchscreen less precise than a physical dial
This is the pick I would put on a heat pump with electric backup heat when the homeowner wants a big readable screen and no learning curve. The manufacturer lists compatibility with forced air gas, oil, electric, hot water and steam, and heat pumps with electric backup. That sentence covers exactly the configuration most ducted heat pumps ship in.
Smart Response technology adjusts the schedule to match how the house warms and cools, and the home screen shows indoor and outdoor temperature, humidity, and a daily forecast. For anyone diagnosing a comfort complaint, those humidity and outdoor readings save real diagnostic time.
One owner of a wide range of heat pumps on r/heatpumps recommended a SmartSensor-equipped thermostat specifically so a Carrier system could be fully used. This Honeywell does not bundle room sensors, so if your rooms are uneven that is a separate purchase. What it does offer is setpoint control and remote scheduling on a screen you can read from the doorway.
The Resideo app handles remote access, geofencing, and energy history, and reviewers report good results on standard 24V systems. It is ENERGY STAR certified, which matters if your utility offers rebates.
How the C-wire requirement changes the install?
A C wire is the common wire, and it supplies constant 24V power so the thermostat does not steal power from the heating circuit. On a heat pump the system cycles more often than a furnace, so a reliable C wire matters more than it does on a gas system. If your wall box has no common wire, the package includes a voucher for a Honeywell C-wire adapter.
It will not work with 120-240V electric baseboard heat, so check that your system is a low-voltage 24V air handler before you order.
Where this Honeywell falls short?
Reviewers note the touchscreen is less precise than a physical dial, and Smart Control features such as geofencing need app setup before they do anything. Heating-only oil furnace setups need a C wire present to work at all, which is the same constraint as the heat pump case.
For a two-stage heat pump where you care about staging behaviour, the Honeywell TH8321WF1001 further down this list reaches three heat stages and handles reversing valve polarity configuration. This one covers a common setup well without the extra depth.
3. ecobee Smart Thermostat Premium Review for Heat Pumps With Backup Strips
ecobee Smart Thermostat Premium – WiFi, Siri & Alexa Built-In, Smart Sensor
- Included SmartSensor solves uneven rooms
- Compatible with 95% of HVAC systems including heat pumps
- Power Extender Kit handles homes without a C wire
- Built-in radar occupancy sensing preheats early
- Air quality monitoring with filter reminders
- Works with Alexa Siri Google Assistant and HomeKit
- Highest price tier among smart thermostats
- Siri and doorbell features need a subscription
- Only one SmartSensor can be the priority target at a time
This is the recommendation that comes up most on r/hvacadvice when someone asks about an air handler wired for aux heat. The Smart Thermostat Premium is the only pick in this roundup that ships with a room sensor in the box, and on a heat pump that sensor is the difference between the compressor heating the hallway and heating the living room.
Compatibility is listed at 95% of HVAC systems, which covers conventional single-stage and multi-stage heat pumps with reversing valve control. The built-in radar occupancy sensor preheats or precools before you arrive rather than reacting after you get home.
The Power Extender Kit in the box is a bigger deal than it sounds. It lets the thermostat install on a 24V system with no common wire by powering the C circuit through the equipment, which removes the single most common reason a heat pump thermostat swap gets abandoned halfway. The air quality monitor adds filter change reminders, useful because heat pumps depend on a clean filter for airflow.
Reviewers value the metal build, the large display, and the fact that the app shows schedules, energy use, and system activity together. On r/heatpumps the SmartSensor gets called out as the reason the system can be fully used rather than just turned on.
What heat pump compatibility actually looks like here?
The Premium drives the reversing valve through the O and B terminals and handles multi-stage heat pump operation, so a two-stage compressor gets proper stage control instead of full capacity all the time. That matters more in cold weather, where running stage two constantly is the difference between a comfortable house and a large power bill.
One limitation shows up in owner feedback: a SmartSensor can be set as the single priority or averaging target at a time, so a very large house needs deliberate sensor placement rather than automatic averaging across many rooms.
Where the premium tier stops paying?
The Siri, doorbell camera, and full smart security functions need an Apple home hub or an ecobee Smart Security subscription, so budget for that separately or ignore those features. It is also the priciest unit in this roundup, and if you live in a small home with even temperatures the sensor advantage largely disappears.
For the same ecosystem at a lower tier, the Enhanced model covers 90% of systems and adds HomeKit plus SmartThings support, and the Essential covers single-stage heat pumps at 2H/1C.
4. ecobee Smart Thermostat Enhanced Review for Multi-Stage Comfort
ecobee Smart Thermostat Enhanced, Programmable Wifi Thermostat
- Highest customer rating of the ecobee models here
- Compatible with 90% of HVAC systems including heat pumps
- Built-in occupancy sensing with preheat and precool
- Power Extender Kit included in the box
- Works with Alexa Google Assistant HomeKit and SmartThings
- Remote control including Apple Watch
- SmartSensors sold separately for multi-room control
- No air quality monitor or smart speaker
- Schedule editing leans on the app
The Enhanced carries the highest customer rating of the three ecobee models in this roundup at 4.4, and for a heat pump home it is the more sensible ecobee choice than the Premium in most cases. You give up the bundled sensor and the air quality monitor, and you get a 4 inch display with the same occupancy sensing behaviour.
Compatibility is listed at 90% of HVAC systems, including heat pumps, and the Power Extender Kit is again in the box. Multi-stage systems and dual-fuel setups fall inside that coverage.
eco+ is the quiet feature here. It uses your routine, local weather, and grid activity to decide when to preheat, which on a time-of-use electricity plan is the difference between heating at the cheap rate and the expensive one. Reviewers who track cost report measurable differences once the schedule assistant is active.
The app works on smartphone and tablet, and it extends to Apple Watch, which is the kind of small convenience that keeps people out of the wall unit. HomeKit and SmartThings support make it the easiest fit for an Apple or SmartThings house.
Why the Enhanced suits a two-stage heat pump?
On a two-stage system, the thermostat’s job is to decide when stage one is enough and when to call for stage two. The occupancy sensing here preheats before you arrive instead of overshooting after, and the eco+ routine logic reduces how often the compressor runs at full capacity in shoulder seasons.
Add ecobee SmartSensors and you can average across rooms, which is the fix for the upstairs bedroom that is always ten degrees warmer than the ground floor.
What you give up versus the Premium?
Room sensors are a separate purchase, which is the real cost difference once you have two or three of them. There is no built-in air quality monitor, so filter reminders depend on your own schedule, and there is no smart speaker in the unit.
If you want the sensor included and do not care about Apple Home support, the Premium covers more HVAC types and keeps the same 3 year warranty.
5. Google Nest Learning Thermostat 4th Gen Review for Heat Pump Automation
Google Nest Learning Thermostat (4th gen) + Nest Temperature Sensor (2nd gen) – Obsidian
- Included temperature sensor prioritises the room that matters
- Works with most 24V systems including heat pumps
- 60 percent larger display with Dynamic Farsight
- Learning schedule plus Adaptive Eco
- Matter compatible with Alexa Siri and Google Assistant
- Programmable maintenance band reduces short cycling
- Fourth gen base is not compatible with third gen Nest backplate
- Not ENERGY STAR rated which limits rebate eligibility
- Setup app can falsely report no power on the R wire
- Learning can overshoot below your preferred temperature
This is the thermostat I would choose if the plan is to set the schedule once and then stop thinking about it. The learning engine builds a schedule from your habits, and Adaptive Eco uses outdoor temperature to pick an away temperature that still protects the house without over-conditioning it.
Compatibility is listed across most 24V systems, including gas, electric, oil, forced air, heat pump, and radiant, with no C wire needed in most homes. That wider system list than most competitors publish is the useful part for heat pump owners.
The included Nest Temperature Sensor is the feature that matters on a heat pump. It lets the thermostat read the room you actually use instead of the hallway where the unit sits, and sensor grouping is supported if you add more than one. The 60 percent larger display with Dynamic Farsight is genuinely readable across a room, which matters in a tall entry hall.
The programmable maintenance band controls the compressor cycle range, and on a heat pump that is a real setting rather than a novelty. Narrowing the cycle band reduces short cycling, and short cycling is what wears out a compressor faster than runtime does.
Where the fourth generation fits a heat pump?
It handles single-stage and conventional multi-stage heat pumps on a standard 24V board and does not need a C wire in most installations. Because it is Matter certified, you can add it to a mixed smart home without being locked into one vendor’s app.
The setup app has a documented complaint where it reports no power on the R wire even when voltage is present, and some reviewers found Google support unhelpful on that error. Check your wire count before you start.
What you should know before buying?
The fourth generation base will not fit a third generation Nest backplate, so replacing an existing Nest means dealing with the wiring again rather than swapping the base. It is also not ENERGY STAR rated, which can rule it out if your utility only rebates certified models.
Designed for US 24V systems, it needs a heat link to work in the UK. And if you dislike the minimalist dial, note that owners report the learning can drift the temperature lower than they set.
6. ecobee Smart Thermostat Essential Review for Budget Heat Pump Upgrades
ecobee Smart Thermostat Essential – WiFi Thermostat, Energy Star Certified
- Lowest-cost ecobee option with app control
- ENERGY STAR certified with estimated 23 percent annual savings
- Supports heat pump systems at 2H/1C
- eco+ time-of-use preheat and precool
- Free software upgrades
- Works with HomeKit Google Assistant and Alexa
- Power Extender Kit and trim kit sold separately
- Narrower compatibility ceiling than Enhanced and Premium
- No occupancy radar and SmartSensor is an extra purchase
- Plastic build
This is the ecobee to buy on a straightforward single-stage heat pump where you want the app and the schedule without spending for sensors you will not use. It supports conventional 2H/1C and 1H/2C systems, heat pumps at 2H/1C, boilers, dual fuel, and most 24V gas, oil, and electric equipment.
The 3.74 inch colour touchscreen is the most intuitive interface of any ecobee model, and free software upgrades mean the unit does not age out the way a locked thermostat would.
eco+ brings indoor humidity detection, a schedule assistant, and time-of-use preheat and precool. The humidity readout is genuinely useful in a humid climate, where a heat pump running continuous cooling to strip moisture needs a dual setpoint rather than a cooling-only schedule.
Owners treat this as the value entry into the ecobee app, and the app experience is identical in shape to the more expensive models. If you already run ecobee elsewhere, this keeps everything in one place.
Does it cover your heat pump?
It does, for single-stage systems. The listed compatibility covers heat pumps at 2H/1C, which is the standard configuration for the vast majority of ducted residential heat pumps. You can confirm your system with the manufacturer compatibility checker before ordering.
The caveat is the ceiling. Reviewers are explicit that compatibility is narrower than the Enhanced and Premium, so a 2H/2C or 3H/2C system may not be supported. That is where you should step up to the Enhanced or to a Honeywell.
The install costs you should plan for
The Power Extender Kit and the trim kit are sold separately on this model, unlike the two ecobee models above it. If your home has no common wire, budget for that kit or the install becomes awkward.
SmartSensors are also an extra purchase, and there is no occupancy radar, so preheat behaviour depends on the schedule rather than on presence detection. For a first smart thermostat on a simple system, that trade is worth it.
7. Sensi Touch 2 Review for Simple Heat Pump Installations
Sensi Touch 2 Smart Thermostat Wi-Fi, Alexa, Energy Star Certified, ST76
- Listed compatible with heat pumps furnaces boilers and air conditioners
- App-guided install using universal Bluetooth
- ENERGY STAR certified
- Usage reports equipment alerts and filter reminders
- States it does not sell personal information to third parties
- 3 year warranty
- C-wire required
- Room sensors sold separately
- Fewer smart home integrations than the major ecosystems
The Sensi Touch 2 is the one I recommend to anyone who wants a thermostat that does not phone home to a data broker. Sensi states it does not sell personal information to third parties, and for a house that publishes occupancy data to a cloud service, that is a real consideration rather than a marketing line.
It is listed for heat pumps along with air conditioners, boilers, and furnaces, and it is ENERGY STAR certified with a claimed savings figure of about 23 percent on HVAC energy.
The install experience is the standout. Universal Bluetooth guides the wiring steps inside the app, so the phone tells you which terminal to use rather than leaving you to interpret a printed diagram. That matters on a heat pump because the O versus B reversing valve choice is the mistake that silently breaks heating and cooling.
Once running, the maintenance side is solid: usage reports, equipment alerts, and filter replacement reminders. Voice control runs through Alexa, Google Assistant, and SmartThings.
What works and what does not on a heat pump?
It runs a conventional 24V heat pump with the standard O and B reversing valve and can handle the auxiliary heat terminals on an air handler with strips. What it will not do is anything clever with staging or balance point logic, so it suits a single-stage system better than a three-stage one.
A C wire is required, which in an older home means a small electrical job before you even start. Check for the common wire first.
Who should pass on this one?
Sensi Room Sensors are sold separately, so multi-room balancing is an added cost. The integration list is shorter than the ecobee and Google options, and it runs under the Copeland brand name, which some buyers find unfamiliar compared with the big three names.
If you run Home Assistant and want local control, the YoLink further down is a better fit. If you want Apple Home support out of the box, the ecobee models cover you.
8. Honeywell TH8321WF1001 Review for Multi-Stage Heat Pumps
Honeywell TH8321WF1001/U Wi-Fi 8000 for Residential or Commercial Use, Stages Up to Up to 3 Heat/2 Cool
- Broadest staging in this roundup at 3 heat and 2 cool
- Highest average customer rating at 4.5
- Runs auxiliary heat without extra modules
- Configurable reversing valve polarity for different manufacturers
- Setpoint limits and thermostat lockout
- 5 year warranty with proof of professional installation
- Older dated design compared with touchscreen models
- Screen dims and cannot be kept lit
- Advanced options need the 4-digit code on the backplate
- Requires 24V power and ground from the air handler
On a three-stage heat pump this is the most capable thermostat in the roundup, and nothing else here comes close on staging depth. It supports up to 3 heat stages and 2 cool stages, and it runs auxiliary heat without extra modules, which removes a common source of install cost on a heat pump with backup strips.
It carries the highest average customer rating of anything we analysed at 4.5, and much of that comes from HVAC professionals who install the same unit repeatedly.
The configurable reversing valve polarity setting is the detail that separates it. Rather than guessing which way your outdoor unit wants the reversing valve energised, you set the polarity in software, so the O versus B mistake gets fixed without re-terminating a wire.
Setpoint limits and thermostat lockout let you cap how cold or hot a space can be set, which is the setting a landlord or an energy-conscious family reaches for. Separate fan-only scheduling gives you ventilation without tying it to the heat schedule.
Why staging depth matters on a heat pump?
A multi-stage compressor at stage one moves roughly half the capacity it moves at stage three. On a mild day when the house only needs half the heat, a thermostat that can call stage one is running the compressor less and saving money, and the same logic applies to two-stage cooling in summer.
The unit also requires 24V power and ground from the air handler, so older wiring without a ground needs attention before install. The manufacturer warranty runs 5 years with proof of professional installation.
What you give up for that control?
The design is dated next to the touchscreen units here, and the screen dims rather than staying lit. Advanced options hide behind a 4-digit code printed on the backplate, so this rewards a confident installer more than a self-guided homeowner.
Remote access is app-based rather than voice-first, and one reviewer reported a unit failing after a power event and trouble getting the warranty honoured. If you want a screen you can actually use, the Honeywell X8S is the modern sibling.
9. Honeywell Home X8S Premium Review for Large Zoned Homes
Honeywell Home X8S Premium Smart Wi-Fi Thermostat, White
- Supports up to 3H/2C heat pumps with electric backup
- 5 inch customizable display
- Advanced occupancy and presence detection
- Indoor air quality humidity and Feels Like comfort control
- Multiple remote sensors averaged across rooms
- Matter certified with Alexa Google Assistant and Apple Home
- First Alert app feels less polished than competing apps
- Remote control routes through the First Alert app
- Apple Home via Matter stopped recognising the thermostat for one reviewer
- Advanced setup assumes HVAC knowledge
If your heat pump serves a house where rooms run ten degrees apart, sensor averaging is the feature that decides your comfort, and the X8S supports averaging across multiple remote sensors. It is also the only unit here listed for heat pumps with electric backup up to 3 heat and 2 cool, so it handles the deep staging cases without an extra module.
The 5 inch display, humidity and ventilation control, and the Feels Like comfort setting make it the most dashboard-like option in this roundup. Occupancy and presence detection handle the away savings.
Matter certification puts it in the same bucket as the current Google and ecobee options, so it joins Alexa, Google Assistant, and Apple Home without a vendor bridge. Doorbell camera view and two-way intercom work with First Alert VX1 and Ring streaming doorbells, though those are not included.
A C wire is required, but the package includes a voucher for a Honeywell Home C-wire adapter, which softens that requirement in older homes. Reviewers on heat pumps specifically report using it on multi-stage systems without staging complaints.
Is it worth it for a heat pump with backup strips?
Yes, if your house is large or zoned. The combination of 3H/2C heat pump support with electric backup and multi-zone sensor averaging addresses the two failures that show up most on a ducted heat pump: the second stage running constantly, and one wing of the house staying cold.
It also supports hot water heat and forced air gas, oil, or electric, so it can carry a mixed system, though it will not work with 120-240V electric baseboard heat.
The software is the weak point
Reviewers describe the First Alert app as basic compared with the ecobee and Google apps, and remote control routes through that app rather than a Honeywell-branded one. One reviewer lost Apple Home via Matter after a few weeks, so treat the Matter pairing as something to recheck.
Advanced setup assumes you can answer HVAC wiring questions yourself, and the unit needs 2.4 or 5.0 GHz Wi-Fi on an 802.11ax, ac, a, b, g, or n router. One isolated report described a unit sold as new that was still registered to another account, so check that on arrival.
10. YoLink Thermostat 2 Review for Heat Pumps and Home Assistant
YoLink Thermostat 2, Smart Heat Pump Thermostat, YS4004
- Designed specifically for heat pumps with dual-stage control
- LoRa range up to a quarter mile
- Remote sensor can act as the controlling temperature source
- Works with Alexa Google Home IFTTT and Home Assistant
- Part of a wider ecosystem with leak sensors and water shutoff
- Lowest price in the roundup
- YoLink hub required and sold separately
- Schedule limited to four time slots per day with no copy function
- No high and low temperature alerts
- App insists on the schedule with no true hold state
- Intermittent app connectivity reported by some reviewers
This is the only thermostat in the roundup built specifically for heat pumps rather than adapted from a furnace platform, and it comes in 1-stage and 2-stage configurations. The dual-stage heating and cooling control is the headline, with ECO mode for energy saving and remote access through the YoLink app.
The LoRa radio reaches up to a quarter mile, which is a different order of magnitude from Wi-Fi range and is the reason to consider it. Owners on Home Assistant and larger properties report connectivity that holds up where Wi-Fi-only units drop.
It supports up to two YS8007-UC remote sensors, and you can designate one as the controlling temperature source so the thermostat reads the bedroom rather than the hallway. That solves the uneven-floor problem without buying a hub of sensors.
For a Home Assistant household, local integration is the deciding factor. Owners in that community compare it favourably against Wi-Fi-only thermostats that drop out, and it sits inside a wider ecosystem with leak sensors and water shutoff valves.
What heat pump setups it handles?
It is rated for heat pumps specifically, with dual-stage heating and cooling available, and it installs on a 24VAC system with a C wire. The one thing to watch is the heat pump and gas mode selector switch, which several owners say can be set wrong and cause confusion when the system misbehaves.
Only one temperature source acts as the control point at a time, with no averaging and no custom rules, and changing the active sensor is buried in a menu rather than sitting on a dedicated screen.
Where the software holds it back?
Scheduling is limited to four time slots per day with no way to copy settings across days, there is no high and low temperature alerting, and the app pushes you toward the schedule instead of offering a true hold state. Some reviewers also reported intermittent app connectivity errors.
The hub is required and sold separately, and the plastic build is plain, but it is the lowest price in this roundup and the only unit with a quarter-mile radio range.
Heat Pump Compatibility: What Your System Actually Needs?
Every thermostat here runs on the same 24V low voltage control circuit. R carries power, W calls for heat, Y calls for cooling, and O or B energises the reversing valve that switches the heat pump between modes. AUX or E terminals trigger the backup electric heat strips. If your system uses those terminals, any of the ten units above can drive it.
Three heat pump configurations need extra attention. A single-stage ducted heat pump with no backup heat is the easy case, and the Nest Thermostat, ecobee Essential, and Sensi Touch 2 all handle it. A two-stage system needs staging control, which points to the ecobee Enhanced or a Honeywell. A ductless mini-split is a different category entirely, because those systems use infrared line-of-sight control rather than 24V wiring.
Then there is the one that catches people. Inverter-driven and communicating heat pumps from Carrier, Lennox, Trane, and Mitsubishi use a proprietary protocol to coordinate the outdoor and indoor units. A commenter on Hacker News put it plainly: the best thermostats are not fully compatible with inverter driven heat pumps, and any inverter heat pump will run best with a communicating thermostat. Keep the manufacturer unit. Replacing it with one of the ten picks here means the system loses capacity modulation and reverts to fixed output.
Dual-fuel systems, where a heat pump handles cooling and a gas furnace handles backup heating, need a thermostat that can switch between heat sources. Every model here except the strictly single-stage entries will do it, but the staging logic is what keeps it efficient.
Auxiliary Heat Lockout and Balance Point Settings
Auxiliary heat is not bad for a heat pump, it is expensive. Electric resistance strips convert every watt into heat at roughly three times the running cost per hour of the heat pump, so the goal is to let the compressor work as long as the balance point allows.
The balance point is the outdoor temperature where the heat pump can no longer meet the setpoint on its own. Below it, the strips take over. Setting that lockout temperature too high is the single most common reason a heat pump owner sees a winter bill that does not match their expectations, and default thermostat settings are often set too high.
A reasonable starting point for most homes is a lockout between 20 and 30F, raised toward 35 to 40F in mild coastal climates and lowered toward 10 to 15F in northern climates where the furnace or gas backup is primary. Cold climate heat pumps in our cold climate heat pump guide change these numbers substantially because the compressor is designed to carry the load further down.
In a dual-fuel system the same setting acts as the switchover point between the heat pump and the gas furnace. In an all-electric system with heat strips, it decides how often you pay resistance rates.
C-Wire, O/B Reversing Valve, and 24V Wiring Before You Buy
Count your wires first. A heat pump with backup heat typically needs R, W, Y, and O or B at minimum, and the auxiliary terminal as well, which is why owners with only four conductors available hit a wall. If a fifth wire is needed and it is not there, an electrician can add a common wire, which is a small job but not free.
The O versus B mistake deserves its own warning because it produces no error message. One of the two wires energises the reversing valve to switch the outdoor unit into heating mode. Wire it to the wrong one and your heat pump cools when you ask for heat and heats when you ask for cooling. Several thermostats here let you fix that in software instead, and the Honeywell TH8321WF1001 has configurable reversing valve polarity as a first-class setting.
The O/B convention also varies by manufacturer, which is why you should confirm the polarity during commissioning rather than assuming. Run the system in cooling mode at the thermostat and verify the outdoor unit is actually reversing.
Finally, note the power requirements. The ecobee Premium, Enhanced, and Honeywell RTH9600WF all require a C wire. The ecobee Premium and Enhanced include a Power Extender Kit so you can power the common circuit through the equipment. The ecobee Essential and Sensi Touch 2 need one bought separately, and the Nest Thermostat and Nest Learning Thermostat run without one in most homes but may need it when a heat pump is involved.
Frequently Asked Questions
Can you use a smart thermostat with a heat pump?
Yes. A smart thermostat works with a heat pump as long as your system uses a standard 24V control board with an O or B reversing valve wire. The thermostat sends low voltage signals to call for heat, call for cooling, switch the reversing valve, and stage the compressor. Communicating and inverter-driven systems are the exception, since they need the thermostat supplied with the outdoor unit.
What is the best smart thermostat for a heat pump with auxiliary heat?
The ecobee Smart Thermostat Premium is our pick because it is listed as compatible with 95 percent of HVAC systems, handles the reversing valve and backup heat terminals, includes a room sensor in the box, and ships with a Power Extender Kit for homes without a C wire. The Honeywell Home RTH9600WF is the alternative when you want a large display and explicit heat pump with electric backup support.
At what temperature should a heat pump switch to auxiliary heat?
For most homes a lockout between 20 and 30F is a sensible starting point. Raise it toward 35 to 40F in mild coastal climates and lower it toward 10 to 15F in northern climates where a gas furnace handles backup heat. The lockout temperature is the balance point at which the compressor can no longer meet the setpoint and the electric strips or gas burner takes over.
Is auxiliary heat bad for my heat pump?
No, auxiliary heat does not damage a heat pump, but it costs far more to run. Electric resistance strips generate heat directly, so they cost roughly two to three times more per hour than the heat pump. Setting the lockout temperature as low as your climate allows keeps the compressor working longer and cuts the amount of expensive backup heat you buy.
Why do HVAC contractors push back on Nest thermostats?
The objections usually come down to wiring and staging. Nest thermostats do not control a third heat stage, and a heat pump installation may require a C wire that the homeowner assumed they did not need. Contractors also carry familiarity with Honeywell and ecobee units that can drive auxiliary heat and multi-stage compressors more fully. These are configuration limits, not quality judgements.
Do smart thermostats work with variable speed heat pumps?
Not fully. Variable speed and inverter-driven heat pumps negotiate capacity between the outdoor and indoor units over a proprietary protocol, and they run best with the communicating thermostat supplied by the manufacturer. A third-party smart thermostat will still control the system, but you lose capacity modulation and the system reverts to fixed output cycles.
Final Verdict for Heat Pump Owners
If your heat pump runs on a standard 24V control board, the Google Nest Thermostat is our top pick and the safest default choice for a single-stage system, with the deepest install base of anything in this roundup behind it. For a heat pump with backup strips and uneven rooms, the ecobee Smart Thermostat Premium is the strongest alternative among the best smart thermostats for heat pumps we reviewed, because the room sensor is included and the Power Extender Kit solves the most common install blocker.
Check your wire count and confirm whether your outdoor unit is communicating before you order. Then set the auxiliary heat lockout as low as your climate allows. Updated for 2026, and if your system is ductless rather than ducted, start with our ductless heat pump guide instead.