No C Wire Options
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Lennox S40 (22V24) S40 (22V24) Smart Thermostat
Features
- WiFi and Alexa enabled for remote access
- 7-inch high-resolution color touchscreen
- Compatible with 4-wire standard thermostat cables
- Geo-fencing with One-Touch Away Mode
- On-demand weather with 7-day forecasts
- Works with most 24VAC HVAC systems
General specs
- Brand: Lennox
- Model: S40 (22V24)
- Seller: Retailer
- ID: B0C9R25DXF
- Features: Programmable, High Efficiency, Geo-Fencing, Remote Access, One-Touch Away Mode, Smart Away, On-Demand Weather, live weather data, seven day forecasts, Test on entire system or individual components, Service Panel for real-time monitoring
- Warranty: 10 year warranty against manufacturing defects
- Screen Size: 7 inch
- Screen Type: high resolution color, touchscreen
- Connectivity: WiFi, Wi-Fi, Alexa Enabled
- Model Number: S40, 22V24
- Control Technology: Smart Zoom System (iHarmony), PureAi S Air Purification System
- System Compatibility: Communicating System Control, 4-wire standard thermostat cables, most 24VAC ovens, air conditioners, air conditioning processors, heat pump (up to 3-stage heat and 2 cooling stages), traditional HVAC systems with optional Equipment Interface Module (EIM)
- Accessory Compatibility: Smart Room Sensor, Smart Air Quality Monitor, Wireless Expander
- Installation Requirement: certified HVAC loader for proper installation, Easy Installation
- First listed by seller: April 15, 2026
If you are interested in more details, you can find full information on the seller's page.
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Shipping options
Delivery to 
United States
United States
Available
This smart thermostat is for the homeowner who wants to simplify their daily routine. It helps you manage your home's comfort from anywhere, like adjusting the temperature before you leave work or checking on your system while traveling.
Think of it as your home's personal climate manager, not just a programmable device. The 7-inch touchscreen makes setup intuitive, and the Lennox Smart app lets you control everything remotely. You can use geo-fencing to automatically switch to Away Mode when you leave, saving energy without a second thought.
Features like On-Demand Weather keep you informed, and compatibility with Alexa allows voice commands for hands-free adjustments. It works with most HVAC systems, including heat pumps and air conditioners, and supports accessories like room sensors for precise temperature control. Installation requires a certified HVAC professional to ensure warranty coverage and optimal performance.
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| Brand | Lennox | Honeywell | Honeywell | Walfront | Honeywell Home | BECA |
| Model | S40 (22V24) | TH6320WF2003 | TH8321WF1001 | X7S | BHT 8000GBLW | |
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| Price | €946.88 | €204.35 | €157.97 | €12.90 | €134.79 | €46.89 |
| Seller | Retailer | Retailer | Retailer | Retailer | Retailer | Banggood |
| Update | May 29, 2026 | Jun 24, 2026 | Jun 24, 2026 | May 20, 2026 | Jun 24, 2026 | May 9, 2026 |
| Connectivity | WiFi, Wi-Fi, Alexa Enabled | Wi-Fi | WiFi | WiFi | WiFi (2.4 or 5.0 GHz), 802.11ax/ac/a/b/g/n wireless router | |
| Compatibility | Heat Pump, Conventional | Stages up to 3 Heat / 2 Cool | Heat Pump with Electric Backup (up to 3 heat/2 cool), Conventional Systems (2 heat/2 cool), Hot Water Heat, Forced Air (gas, oil, or electric) | |||
| Type | Touchscreen Thermostat | Wall Thermostat | Smart Thermostat | WiFi | ||
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