Imagine a room thermostat

...with a slim, modern design.
...that’s backward and forward compatible with multiple heating systems.
...that supports greener energy systems.

The Honeywell Home DT4 Room Thermostats: Where functionality meets elegance

eye-pleasing design icon

Designed for installers. Made for users.

DT4 Room Thermostats combine slim, modern design with simple functionality. They’re designed to be easy to use, with features that are easy to love.

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Backward and forward compatible.

DT4 Room Thermostats work with OpenTherm®, heat pumps and legacy systems. Available wired or wireless, they’re made to suit a wide variety of homes and applications, so you can choose what’s right for your customer.

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Supporting greener energy systems.

DT4 Room Thermostats can be installed standalone or as part of a wider home comfort solution, with products such as the HCC100 underfloor multi-zone controller. They’re also compatible with hybrid and greener energy systems, as well as a range of energy-efficient solutions.

Parent reading a book with a child.

The only thermostat you need

As the first point of contact for homeowners, installers know exactly what features household appliances should have. That’s why we listened to feedback from professionals when developing the DT4 Room Thermostats, to ensure they deliver everything you and your customers need – just like you imagined.

The DT4 range

Product comparison Table



DT40WT20 (white)
DT40GT21 (grey)
DT40BT22 (black)
YT42WRFT20 (white)
YT42GRFT21 (grey)
YT42BRFT22 (black)
DTS42WRFST20 (white)
DTS42GRFST21 (grey)
DTS42BRFST22 (black)


White, Grey, Black White, Grey, Black White, Grey, Black


yes yes yes


YES (included) YES (included) YES (included)


3.5 years 1.5 years 1.5 years


BDR91A evohome, ST9000 Timer range, HCC100, BDR91A, HCE80, HCC80


Boilers, heat pumps, zone valves, underfloor, solid fuel boiler, electric heater Boilers, heat pumps, zone valves, underfloor, solid fuel boiler, electric heater, replacement market Zoning, underfloor, replacement market


5 years 5 years 5 years

The DT4 range brochure

Discover more about the full DT4 range of thermostats.

Installer tutorials

Get the right training for the right job.

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