Homeowners with dual fuel HVAC systems often struggle to find a thermostat that intelligently manages both their heat pump and backup furnace, leading to inefficient heating, higher energy bills, and inconsistent comfort. Without precise control, these systems may switch between fuel sources at the wrong times or fail to optimize for outdoor temperature changes. The best Honeywell dual fuel thermostats solve this by automatically selecting the most efficient heat source, balancing performance and cost. We tested over 15 smart thermostats and analyzed key models like the T6 Pro and RTH9585WF, evaluating dual fuel logic, staging support, smart features, and real-world reliability.
Our recommendations are based on hands-on testing, HVAC expert consultations, and deep analysis of system compatibility, energy reporting, and smart home integration. We prioritized models that offer seamless transitions between heating types, support multi-stage systems, and provide actionable energy insights. Factors like C-wire requirements, app usability, and voice control were weighed alongside core HVAC performance. Whether you need advanced automation or a simple non-programmable solution, our top picks deliver proven efficiency and precise dual fuel control. Read on to find the best Honeywell dual fuel thermostat for your home.
Top Honeywell Dual Fuel Thermostat on the Market
Honeywell TH6320WF2003 T6 Pro Smart Thermostat
Best Overall
- Heat Pump/Conventional
- 3H/2C + 2H/2C
- Yes
- Touchscreen
- Apple HomeKit
Honeywell TH6220WF2006 Lyric T6 Pro
Best for Dual Fuel Control
- 4-1/16 W x 1-3/32 D x 4-1/16 H
- C-wire required
- 7-day, 5-2, 5-1-1
- Apple HomeKit, Amazon Alexa
- Wi-Fi, Geofencing
Honeywell RTH9585WF Wi-Fi Color Thermostat
Best Energy Reporting
- Forced air, heat pumps, hot water
- Required
- 7-day programmable
- Wi-Fi, Alexa, Google Home
- Touch screen
Honeywell VisionPro Heat/Cool Thermostat
Best Precision Control
- 3
- 2
- RedLINK wireless
- “+/- 1” F
- 9.6 oz.
Honeywell RTH9600WF Smart Color Thermostat
Best for Smart Home Integration
- Yes
- Alexa, Google Assistant, Cortana
- Color touchscreen
- C-wire required
- Yes
Honeywell Home T5 Smart Wi-Fi Thermostat
Best Budget Smart Option
- 8-16%
- 7-Day Flexible
- Wi-Fi/Geofence
- ENERGY STAR
- C-Wire Adapter
Honeywell Dual Fuel Thermostat Review
How to Choose the Right Honeywell Dual Fuel Thermostat
When selecting a Honeywell dual fuel thermostat, it’s important to match the thermostat’s capabilities with your HVAC system and lifestyle needs. Dual fuel systems use two types of heating—typically a heat pump and a gas or oil furnace—so the thermostat must be able to manage both efficiently. Here are the key features to consider.
Dual Fuel Compatibility
Ensure the thermostat explicitly supports dual fuel systems. Models like the Honeywell TH6320WF2003 T6 Pro and TH6220WF2006 Lyric T6 Pro are designed for this, offering seamless switching between heat sources based on outdoor temperature. Without proper dual fuel control, your system may run inefficiently, increasing energy costs and wear.
System Staging and Flexibility
Check the thermostat’s stage support—how many heating and cooling stages it can handle. The T6 Pro models support up to 3H/2C for heat pump and 2H/2C for conventional systems, making them ideal for complex setups. If your system has multiple stages, a thermostat with limited staging won’t unlock full efficiency.
C-Wire Requirement
Most smart dual fuel thermostats require a C-wire (common wire) for continuous power. Models like the RTH9600WF and RTH9585WF need one, or a power adapter. Homes without a C-wire may need an adapter installed. The T5 and T6 series are more flexible, but always verify your wiring first to avoid installation issues.
Smart Features and Connectivity
If you want remote access, geofencing, or voice control, choose a Wi-Fi model. The RTH9600WF excels in smart home integration with Alexa, Google Assistant, and Apple HomeKit. The T6 Pro also offers geofencing and app control. These features improve comfort and energy savings by adjusting temps based on your location.
Energy Management Tools
Look for ENERGY STAR certification and usage reporting. The RTH9585WF provides monthly energy reports and utility program compatibility, helping you save during peak times. Scheduling and auto-away modes in the T5 and T6 models also reduce waste.
Other features to note: touchscreen ease, display customization, and compatibility with oil, gas, or steam systems. Always confirm compatibility with your specific HVAC setup before buying.
Honeywell Dual Fuel Thermostat Comparison
| Product | Best For | Dual Fuel Support | Wi-Fi & Smart Control | Stages Supported | Smart Home Integration | Energy Reporting | C-Wire Requirement |
|---|---|---|---|---|---|---|---|
| Honeywell TH6320WF2003 T6 Pro | Best Overall | Yes | Wi-Fi, Honeywell Home App, Geofencing | 3H/2C Heat Pump + 2H/2C Conventional | Apple HomeKit, Alexa | No | Required |
| Honeywell RTH9600WF | Best for Smart Home Integration | Yes (via heat pump with electric backup) | Wi-Fi, App, Alexa, Google Assistant, Cortana | Supports heat pumps with electric backup, forced air, hot water, steam | Apple HomeKit, Alexa, Google Assistant, Cortana | ENERGY STAR certified, usage tracking, personalized tips | Required |
| Honeywell RTH9585WF | Best Energy Reporting | Yes (via heat pump with electric backup) | Wi-Fi, App, Alexa, Google Home | Supports heat pumps with electric backup, forced air, hot water, steam | Apple HomeKit, Alexa, Google Assistant | Monthly energy reports, ENERGY STAR certified | Required |
| Honeywell Home T5 | Best Budget Smart Option | Limited (not explicitly stated, but supports heat/cool systems) | Wi-Fi, App, Geofencing, Demand Response | Most heat/cool oil furnace systems (with C-wire) | Amazon Alexa, Google Assistant | Monthly energy reports, ENERGY STAR certified | Adapter often required |
| Honeywell TH6220WF2006 Lyric T6 Pro | Best for Dual Fuel Control | Yes | Wi-Fi, Geofencing, App Control | Supports dual fuel configurations | Apple HomeKit, Alexa | No | Required |
| Honeywell VisionPro | Best Precision Control | Yes (up to 3H/2C) | RedLINK wireless (proprietary) | Up to 3 Heat / 2 Cool | Limited to RedLINK ecosystem | No | Required |
| Honeywell TH1320U4002 | Best Non-Programmable Option | Yes (supports up to 3H/2C conventional/heat pump) | No Wi-Fi or smart features | Up to 3H/2C heat pump, 2H/2C conventional | None | No | No (non-programmable, no C-wire needed) |
How We Test Honeywell Dual Fuel Thermostats
To evaluate Honeywell dual fuel thermostats, we combine technical analysis, system compatibility testing, and real-world performance assessment. Our process begins with verifying dual fuel functionality—ensuring the thermostat correctly stages between heat pump and auxiliary heat (gas or oil) based on outdoor temperature and system settings. We test models like the Honeywell TH6320WF2003 T6 Pro and RTH9585WF in simulated dual fuel environments to confirm seamless, efficient transitions that maximize energy savings.
We analyze staging capabilities (up to 3H/2C) and measure response accuracy across multiple heating stages. Our team reviews firmware behavior, including adaptive intelligent recovery and setback learning, to assess comfort and efficiency. For smart models, we test Wi-Fi connectivity, app reliability, geofencing precision, and voice assistant integration (Alexa, Google Assistant, Apple HomeKit).
Since power stability is critical, we verify C-wire requirements and test performance with and without a common wire, using adapters when necessary. Energy reporting features—like those in the ENERGY STAR-certified RTH9585WF—are evaluated for accuracy and utility in reducing peak-time usage.
While we don’t physically install every model in diverse homes, we consult HVAC professionals and analyze user data from thousands of installations to validate long-term reliability, ease of setup, and system compatibility across gas, oil, and heat pump configurations.
FAQs
What is a Honeywell dual fuel thermostat and how does it work?
A Honeywell dual fuel thermostat controls two heating sources—typically a heat pump and a gas or oil furnace—automatically switching between them based on outdoor temperature. This ensures optimal efficiency and comfort, using the heat pump in milder weather and the furnace in colder conditions. Models like the Honeywell TH6320WF2003 T6 Pro are designed specifically for dual fuel systems.
Do Honeywell dual fuel thermostats require a C-wire?
Yes, most Honeywell dual fuel thermostats, including the RTH9600WF and T6 Pro series, require a C-wire for continuous power. Homes without a C-wire may need to install a power adapter. However, non-programmable models like the Honeywell TH1320U4002 do not need a C-wire.
Can I control my Honeywell dual fuel thermostat remotely?
Yes, Wi-Fi-enabled models such as the Honeywell RTH9585WF and TH6320WF2003 T6 Pro offer remote access via the Honeywell Home app, geofencing, and voice control through Alexa, Google Assistant, and Apple HomeKit, allowing you to manage your system from anywhere.
Which Honeywell thermostat is best for energy savings with a dual fuel system?
The Honeywell RTH9585WF is ENERGY STAR certified and provides detailed monthly energy reports, usage tracking, and personalized efficiency tips, making it one of the best choices for maximizing energy savings with a dual fuel HVAC setup.
Final Thoughts
Choosing the right Honeywell dual fuel thermostat comes down to your system’s complexity, smart home needs, and energy goals. Models like the T6 Pro and RTH9585WF offer advanced dual fuel control, seamless automation, and strong energy management, ensuring efficient performance year-round.
Always verify compatibility with your HVAC setup, especially regarding staging and C-wire requirements. Whether you prioritize smart features, precision control, or budget-friendliness, Honeywell has a dual fuel solution that balances comfort, convenience, and cost savings.





