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White rectangular smart thermostat with smooth finish and subtle display, about six by four inches

Sensi Smart Thermostat

SKU CH-MSF4-EWMBZ

Wi-Fi thermostat with Alexa control and Energy Star certification saves about 23% on HVAC energy

  • ColorWhite
  • Privacy protected — personal data never sold to third parties
  • Easy DIY install with built-in level and step-by-step app guidance
  • Saves about 23% on HVAC energy via ENERGY STAR certified features
  • Simple configuration fits existing thermostat space without wall repairs
  • Smart maintenance alerts monitor system performance and remind filter replacement

Smart thermostat with Wi-Fi and Energy Star

The Sensi ST55 is a white smart thermostat designed for residential heating and cooling systems. It connects to a 2.4 GHz Wi-Fi network for remote control and monitoring. Energy Star certification indicates the device can help reduce HVAC energy use by about 23 percent. The unit includes a built-in level for straight mounting.

Check HVAC wiring and Wi-Fi band before ordering

Most installations do not require a common wire, but the thermostat can be powered by battery or a C-wire if present. Verify that the existing equipment is compatible with the wiring terminals on this model. The home network must broadcast a 2.4 GHz signal because the thermostat does not support 5 GHz bands. The wall opening should accommodate the 5.875 by 3.75 inch footprint.

Fits standard thermostat locations

The thermostat occupies the same footprint as a traditional unit so patching and painting are unnecessary. Physical buttons and a backlit display provide local control without a phone. Remote access, usage reports and smart maintenance alerts are delivered through the companion app. Privacy protection means personal data is not sold to third parties.

Highlights

  • Privacy protected — personal data never sold to third parties
  • Easy DIY install with built-in level and step-by-step app guidance
  • Saves about 23% on HVAC energy via ENERGY STAR certified features
  • Simple configuration fits existing thermostat space without wall repairs
  • Smart maintenance alerts monitor system performance and remind filter replacement

Specifications

BrandSensi
ColorWhite

Questions about this item

Does the ST55 thermostat include a C-wire adapter or must one be purchased separately?

The ST55 works with most HVAC systems without a common wire, so a separate C-wire adapter is not required for typical installations.

Which model should I choose between the Sensi Wi-Fi Thermostat and the Sensi Touch Wi-Fi Thermostat?

Choose the Sensi Touch if you want a colour touchscreen display; choose the standard Sensi Wi-Fi model if a basic backlit display suits you.

What does the claimed 23% energy saving mean for my actual heating and cooling bills?

The ENERGY STAR certification indicates the ST55 can reduce HVAC energy use by about 23% through flexible scheduling, remote access and usage reports.

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