Honeywell Home

New! Honeywell Home RTH21B Programmable Thermostat — 1H/1C, Flexible 7-Day Schedule (White)

High-performance tools and home improvement made for confident daily results

$52.89

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Why customers choose TaskHolt Tools

The Honeywell Home RTH21B is a reliable programmable thermostat designed for single‑stage heating and cooling. It supports 1 heat/1 cool configurations and can adapt to a variety of systems, including gas, oil, and hot water setups. While it’s not suited for electric baseboard heat, it offers straightforward control that can blend with your daily routines.

Flexible scheduling that adapts to your week

Choose from several scheduling options to match your lifestyle. The 7‑day program covers both workdays and weekends, while 5‑1‑1, 5‑2, or a full 1‑week plan provide tailored routines. If you prefer simplicity, a non‑programmable mode is available for quick overrides.

  • 7‑day programming for comprehensive weekly routines
  • 5‑1‑1 day options for weekday/weekend balance
  • 5‑2 day options for a typical business week

These options help you maintain comfort without constant manual adjustments, offering a practical path to consistent temperatures throughout the day.

Clear display and easy setup

A large, backlit screen keeps information legible from across the room, with a clean typeface that reduces eye strain during nighttime adjustments. The interface emphasizes intuitive controls for everyday use.

  • Backlit display for low-light viewing
  • Bright, readable fonts for quick checks
  • Display settings to tailor brightness and contrast

Install, personalize, and coordinate with your decor

Installation is streamlined with the Honeywell Home UWP wall plate, and you can personalize the look with interchangeable decorative accents in white and gray to harmonize with nearby furnishings.

  • Interchangeable white and gray accent pieces
  • Replacement options for familiar models (RTH2510/RTH2410)
  • Power by two AA batteries (not included) for flexible placement

Whether you’re refreshing a room or upgrading an existing system, the RTH21B offers practical features and a clean appearance to fit a variety of living spaces.

FAQ

Q: What heating and cooling systems are compatible with the RTH21B?

A: Supports 1 heat/1 cool setups (gas, oil, or electric forced air) and hot water heat; not suitable for electric baseboard heat.

Q: What scheduling options does the RTH21B offer?

A: 7-day, 5-1-1 day, 5-2 day, or 1-week programs, plus a non-programmable option.