Will it work with your system?
Works well with
- Phone control and scheduling
- Systems the maker's checker confirms
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 Honeywell Home X8VMC9W/W 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.
Power is where installs stall: its maker says it needs a C wire; its wording is "C-wire required: If your system does not already have one, a voucher to receive a Hone". 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.
Stages, per the maker: up to 3 heat/2 cool. A second-stage wire (W2 or Y2) at your old thermostat needs matching support here. Single- and two-stage systems.
Connectivity: Wi-Fi. It touchscreen.
Not sure of your wiring? The wiring checker reads your system from the terminal letters and checks it against this model's statements.
Also on the listing: dimensions of 0.96 in (D) x 5.24 in (W) x 3.54 in (H), a weight of 1.1 lb and a led.
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 | X8VMC9W/W | Retailer |
|---|---|---|
| Model name | X8S - White w/Sensor | Retailer |
| Dimensions (seller) | 0.96"D x 5.24"W x 3.54"H | Retailer |
| Works with | Touchscreen | Retailer |
| Features (seller) | Auto-Scheduling, Programmable | Retailer |
| Connectivity | Wi-Fi | Retailer |
| Voltage | 30 V | Retailer |
| Display | LED | Retailer |
| Mounting / installation | Wall Mount | Retailer |
| Product weight | 1.1 lb | Retailer |
| C-wire | C-wire required: If your system does not already have one, a voucher to receive a Hone | Retailer |
| Heat / cool stages | up to 3 heat/2 cool | Retailer |
Strong points and weak points
Strong points
- Stages: up to 3 heat/2 cool
- Works with Touchscreen
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 Honeywell Home X8VMC9W/W Smart Thermostat need a C wire?
Does the Honeywell Home X8VMC9W/W Smart Thermostat work with a heat pump?
Other smart thermostats with similar wiring
- Venstar T7900 Smart Thermostat
- Resideo S900 Smart Thermostat
- Honeywell Home TH8320WF1029 Smart Thermostat
- Google Nest BH1252 Learning Thermostat
All smart thermostats in one grid · Every Honeywell Home 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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