Will it work with your system?
Works well with
- Phone control and scheduling
- Systems the maker's checker confirms
Check first if you have
- Line-voltage baseboard heat
- Millivolt gas heaters
What it controls
The Sensi ST25 Smart Thermostat is a smart Wi-Fi thermostat. Systems, per the maker: Works with the HVAC equipment found in most homes.
Power is where installs stall: its maker says no C wire is needed; its wording is "COMMON WIRE REQUIREMENTS: Designed to work without a C-wire in most homes, but for some sys". C-wire options.
The listing doesn't state heat pump support; if you have an O/B wire, confirm with the maker before ordering. Heat pump wiring.
Connectivity: Wi-Fi. It amazon Alexa, Google Assistant, Hand Control, SmartThings.
Tick your terminals in the wiring checker to see whether its maker's statements cover your system.
Also on the listing: dimensions of 0.88 in (D) x 5.07 in (W) x 3.13 in (H), a weight of 4.8 ounces and a lcd.
Warranty, per the listing: 3 years.
Compatibility and specs
These come from the maker's listing for this exact model; the source of each is marked. Anything the maker leaves out is marked not stated.
| Model number | ST25 | Retailer |
|---|---|---|
| Model name | Sensi Lite | Retailer |
| Dimensions (seller) | 0.88"D x 5.07"W x 3.13"H | Retailer |
| Works with | Amazon Alexa, Google Assistant, Hand Control, SmartThings | Retailer |
| Features (seller) | Data Privacy, Easy DIY Install, Energy Savings, Programmable | Retailer |
| Connectivity | Wi-Fi | Retailer |
| Power | Battery or C-wire | Retailer |
| Voltage | 24 V | Retailer |
| Display | LCD | Retailer |
| Mounting / installation | Wall Mount | Retailer |
| Batteries | 2 AAA batteries required. (included) | Retailer |
| Warranty | 3 years. | Retailer |
| Product weight | 4.8 ounces | Retailer |
| C-wire | COMMON WIRE REQUIREMENTS: Designed to work without a C-wire in most homes, but for some sys | Retailer |
| Works with systems | Works with the HVAC equipment found in most homes | Retailer |
Strong points and weak points
Strong points
- No C wire needed (maker)
- Works with Amazon Alexa, Google Assistant
Weak points
- Needs Wi-Fi for smart features
Wiring and install notes
- Compatibility statements are the maker's own. Confirm with the maker's compatibility checker, turn the power off before wiring, and leave line-voltage and furnace work to a licensed electrician or HVAC technician.
Thermostats to compare it with
FAQ
Does the Sensi ST25 Smart Thermostat need a C wire?
Does the Sensi ST25 Smart Thermostat work with a heat pump?
Other smart thermostats with similar wiring
- Levoit LTM-A401S-WUS Smart Thermostat
- Honeywell Home RCHT8610WF2006/W Smart Thermostat
- Honeywell Home RCHT8612WF Smart Thermostat
- Google Nest GA01334-CA Smart Thermostat
All smart thermostats in one grid · Every Sensi control listed
Our take
A fit for phone control and scheduling.
Where to get it
The link goes to this exact model's listing. Check that the box includes the trim plate or C-wire adapter you need, and confirm your wiring with the maker's compatibility checker before you order.
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