Will it work with your system?
Works well with
- Phone control and scheduling
- Heat pump systems
Check first if you have
- Walls without a C wire, unless you add one
- Line-voltage baseboard heat
- Millivolt gas heaters
What it controls
The Sensi 1F87U-42WF Smart Thermostat is a smart Wi-Fi thermostat. Its listing doesn't spell out which heating and cooling systems it supports, so run the maker's compatibility checker before you buy.
Check your wall for a C terminal: its maker says it needs a C wire ("Works with the HVAC equipment found in most homes - a c-wire is required for heat-only, cool-only and heat pump systems"). The C wire guide covers adapters.
The maker states heat pump support ("und in most homes - a c-wire is required for heat-only, cool-only and heat pump systems"), so it can drive an O/B reversing valve. What a heat pump needs from a thermostat.
Connectivity: Wi-Fi. It amazon Alexa, Apple HomeKit, Google Assistant, SmartThings, Vera.
Tick your terminals in the wiring checker to see whether its maker's statements cover your system.
Also on the listing: dimensions of 1 in (D) x 5.88 in (W) x 3.75 in (H) and a digital.
Warranty, per the listing: 5 years with professional installation.
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 | 1F87U-42WF | Retailer |
|---|---|---|
| Model name | Wi-Fi Thermostat for Smart Home, Pro Version | Retailer |
| Dimensions (seller) | 1"D x 5.88"W x 3.75"H | Retailer |
| Works with | Amazon Alexa, Apple HomeKit, Google Assistant, SmartThings, Vera | Retailer |
| Features (seller) | Auto-Scheduling | Retailer |
| Connectivity | Wi-Fi | Retailer |
| Power | Corded Electric | Retailer |
| Voltage | 24 V | Retailer |
| Display | Digital | Retailer |
| Mounting / installation | Wall Mount | Retailer |
| Batteries | 2 AA batteries required. (included) | Retailer |
| Material | Plastic | Retailer |
| Warranty | 5 years with professional installation. | Retailer |
| C-wire | Works with the HVAC equipment found in most homes - a c-wire is required for heat-only, cool-only and heat pump systems | Retailer |
| Heat pump support | und in most homes - a c-wire is required for heat-only, cool-only and heat pump systems | Retailer |
Strong points and weak points
Strong points
- Heat pump support stated
- Works with Amazon Alexa, Apple HomeKit, G
Weak points
- Needs a C wire (maker)
- 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 1F87U-42WF Smart Thermostat need a C wire?
Does the Sensi 1F87U-42WF Smart Thermostat work with a heat pump?
Other smart thermostats with similar wiring
- Vine TJ-919T Smart Thermostat
- LUX TX500E Smart Thermostat
- ecobee EB-STATE7-01 Smart Thermostat
- Honeywell Home TH6220WF2006 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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