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Honeywell Home RTH6580WF Wi-Fi 7-Day Programmable Thermostat (White) vs Sensi Lite Smart Thermostat ST25 (Black)

These are side-by-side facts taken from each product guide: published specifications, strengths and caveats as their sources state them. This page is not a test, a ranking or a verdict about which model is better.

Check Honeywell Home RTH6580WF Wi-Fi 7-Day Programmable Thermostat (White) on AmazonCheck Sensi Lite Smart Thermostat ST25 (Black) on Amazon

Honeywell Home RTH6580WF Wi-Fi 7-Day Programmable Thermostat (White)

24 VAC forced-air, hydronic or heat pump systems that already have a C wire

A Wi-Fi thermostat with a backlit LCD and four schedule periods a day. Honeywell's guides say a C wire is mandatory and that it will not run millivolt or 120/240 V baseboard systems. Setup joins a 2.4 GHz network through a browser page, remote control runs through Total Connect Comfort, and the warranty is one year.

Published specifications

  • Maker: up to 2 heat/2 cool conventional; up to 3 heat/2 cool heat pump
  • Guides: C wire required, primary power; 24 V systems only, no millivolt or 120/240 V
  • Maker: Wi-Fi 802.11 b/g/n, 2.4 GHz; Total Connect Comfort app; Alexa, Google Assistant
  • Guide: 7-day schedule, 4 periods a day; temporary and permanent hold; Smart Response
  • Maker: 3.5 x 5.75 x 1.5 in; backlit LCD; accuracy +/- 1°F
  • Guide and maker: 1-year limited warranty

Strengths

  • Maker lists up to 2H/2C conventional and 3H/2C heat pump staging
  • Guide says it keeps running your system with or without Wi-Fi
  • Maker page, listing and guide agree on the box contents

Caveats

  • C wire is mandatory: without it the thermostat will not power up
  • Listing shows 2 AA batteries and a Honeywell Home app; maker documents do not
  • One-year warranty; removal and reinstallation costs not covered

Check this model on Amazon

Read the full Honeywell Home RTH6580WF Wi-Fi 7-Day Programmable Thermostat (White) guide

Sensi Lite Smart Thermostat ST25 (Black)

Single-stage or one-extra-stage 24 VAC systems on a 2.4 GHz network

Copeland's Sensi Lite thermostat, confirmed by matching UPC. It handles 1H/1C, 1H/2C or 2H/1C conventional systems and 2H/1C heat pumps. Copeland and the listing agree that heat-only, cool-only and heat pump systems need a C wire. Setup requires the Sensi app and an account; the warranty is three years for DIY or pro installs.

Published specifications

  • Maker: stages 1H/1C, 1H/2C or 2H/1C conventional; heat pump 2H/1C; 3-wire zone heat
  • Maker and listing: C wire required for heat-only, cool-only and heat pump systems
  • Maker: 24 VAC, 20-30 Vac rating; hardwire with power stealing; 2 x AAA included
  • Guide: Wi-Fi 2.4 GHz only; Sensi app and account required; Alexa, Google Assistant, SmartThings
  • Maker: 5.07 x 3.13 x 0.88 in; 7-day schedule, 8 periods a day; geofencing; keypad lockout
  • Maker warranty table: 3 years, DIY or professional install

Strengths

  • Listing and maker agree on exactly which systems need a C wire
  • Three-year warranty applies whether you or a contractor installs it
  • UPC matches Copeland's product page, which publishes a specification block

Caveats

  • Only one extra stage: no 2H/2C, and no two-stage heat pump support
  • Heat pump, heat-only and cool-only systems need a C wire
  • Requires the Sensi app, an account and a 2.4 GHz network to set up

Check this model on Amazon

Read the full Sensi Lite Smart Thermostat ST25 (Black) guide

How to choose between them

Choose the Honeywell Home RTH6580WF Wi-Fi 7-Day Programmable Thermostat (White) if your situation matches: 24 VAC forced-air, hydronic or heat pump systems that already have a C wire. Its main caveat: C wire is mandatory: without it the thermostat will not power up.

Choose the Sensi Lite Smart Thermostat ST25 (Black) if your situation matches: Single-stage or one-extra-stage 24 VAC systems on a 2.4 GHz network. Its main caveat: Only one extra stage: no 2H/2C, and no two-stage heat pump support.

Both entries repeat what each guide records. Confirm the model, included parts and availability on the current listing before ordering.

Primary sources

  1. Honeywell Home product page and specifications, WiFi 7-Day Programmable Thermostat RTH6580WF1001/U1 Source for Honeywell Home RTH6580WF Wi-Fi 7-Day Programmable Thermostat (White)
  2. Honeywell Home User Guide 69-2715EF-07, RTH6500WF Smart Series RTH65801006 (listing-supplied PDF) Source for Honeywell Home RTH6580WF Wi-Fi 7-Day Programmable Thermostat (White)
  3. Honeywell Home Quick Start Guide, RTH6500WF Wi-Fi Series (listing-supplied PDF) Source for Honeywell Home RTH6580WF Wi-Fi 7-Day Programmable Thermostat (White)
  4. Copeland product page and specifications for Sensi Lite Smart Thermostat ST25 Source for Sensi Lite Smart Thermostat ST25 (Black)
  5. Sensi Lite installation guide R-5664 (ST25 series) supplied with the Amazon listing Source for Sensi Lite Smart Thermostat ST25 (Black)
  6. Copeland Sensi warranty table by model Source for Sensi Lite Smart Thermostat ST25 (Black)

Primary sources checked .