Specifications

X8S & X8Q Smart Thermostat Description

Feature

Description

Powering Method

Common wire required

Stages:

Up to 3H/2C Heat pump

Up to 2H/2C conventional

Equipment type:

  • Hot water or steam.

  • Gas or oil furnace

  • High-efficiency or mid-efficiency

  • Cool only

  • Humidifier, Dehumidifier, or Ventilator control

Changeover

Manual or Auto Changeover Selectable

System Setting

Em Heat-Heat-Off-Cool-Auto

Fan Setting

Auto-On-Circ


Electrical ratings of X8S & X8Q Smart Thermostat

Terminal

Voltage (60Hz)

Running Current

W (Heat)

20-30 VAC

0.02-1.0 A

W2 (Aux) Heat

20-30 VAC

0.02-1.0 A

E (Not Used)

   

Y (Compressor Stage 1)

20-30 VAC

0.02-1.0 A

Y2 (Compressor Stage 2)

20-30 VAC

0.02-1.0 A

G (Fan)

20-30 VAC

0.02-0.5 A

O/B (Changeover)

20-30 VAC

0.02-0.5 A

L/A (Fault input from heat pump)

20-30 VAC

0.02-0.5 A

U (Humidifier, Dehumidifier, or Ventilator)

20-30 VAC

0.02-0.5 A

Power Consumption: 3.0 VA MAX


Wireless Communication:

Bluetooth: BLE 2.4 GHz

Dual-Band Wi-Fi: 2.4 & 5GHz

Wireless Communication to XRSENSOR Indoor air sensors: 900 MHz (Re-sync time: Wireless sensors re-establish communication within 6 minutes after AC power resumes.)

Radar: 61.5 GHZ.

Temperature Setting Range:

Heating: 40 to 90 °F (4.5 to 32 °C).

Cooling: 50 to 99 °F (10 to 37 °C).

Adjustable high and low range-stop settings in Menu-preferences-Temperature Limits.

Humidification Setting Range:

0% to 90% RH.

Dehumidification Setting Range:

10% to 100% RH.

Humidity Sensor Accuracy:

± 5% RH from 30% to 50% RH at 75 F.

Clock Accuracy:

1 minute per month at 77 °F (25 °C). ± 2 minutes per month over the operating ambient temperature range. Automatically updates when connected to WiFi router and registered to account.


Terminal Designations

Terminals on X8S & X8Q Smart Thermostat

Conventional Systems

Heat Pump Systems

Terminal

Description

Terminal

Description

S/S

Not used by this thermostat.

S/S

No used by this thermostat.

Y

Compressor Stage 1

Y

Compressor Stage 1

Y2

Compressor Stage 2

Y2

Compressor Stage 2

G

Fan Relay

G

Fan Relay

C

24VAC Common wire from secondary side of cooling transformer (if 2 transformers)

C

24VAC Common wire from secondary side of cooling transformer

K*

Connect to K on C-wire adapter

K*

Connect to K on C-wire adapter

U/U

Relay for humidifier, dehumidifier, ventilator.

U/U

Relay for humidifier, dehumidifier, ventilator.

L/A

Not used by this thermostat.

L/A

Heat pump fault

W

Heat Stage 1

O/B

Changeover valve for heat pumps

W2

Heat Stage 2

AUX

 

 

E

E not used by this thermostat. Auxiliary / emergency heat wire should go to AUX.

R

24 VAC Heating transformer

R

24 VAC Heating transformer

Rc

24 VAC Cooling transformer

Rc

24 VAC Cooling transformer

* The THP9045A C-wire adapter is used on heat/cool systems when you only have four wires at the thermostat and you need an extra wire for a common wire. Use the K terminal in place of the Y and G terminals on conventional or heat pump systems to provide control of the fan and the compressor through a single wire the unused wire then becomes the common wire. See THP9045A instructions for more information.