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ecobee 4 Pro

Pro1 - T855i 5/1/1 Programmable or 7 Day or Non-Programmable Wi-Fi Thermostat, 4H/2C with 8 sq. in. Display

Item: T855I
MFR: T855I


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About This Product

Product Info


The New T855i Wi-Fi Thermostat is sold exclusively to HVAC professionals. Here are some of the features that make the T855i the best value in the Wi-Fi market:
  • Easy Setup - If you know how to install any Pro1 thermostat you know how to install a Wi-Fi model. The quickstart guide will walk the homeowner through the WI-FI linking procedure.
  • Universal Subbase - Fast, easy upgrade from existing Pro1 thermostats. No additional wiring necessary as long as C is connected.
  • Private Label - Contractor contact info displayed in mobile app and on magnetic badge of thermostat to generate return business.
  • Smart Grid Capable - Works with many utility incentive programs. Learn more from your professional installer or Pro1 representative.
  • Control From Anywhere - Monitor and control your HVAC system anywhere using your computer, smart phone or tablet.
  • Active Alerts - Receive customized alerts from anywhere. High and low temp. limits, connection status, and more.


  • 7 Day or 5/1/1 programmable
  • Auto Changeover
  • Easy menu driven programming
  • Intuitive wake, leave, return, sleep programming icons
  • 8 square inch display
  • Blue backlight
  • Glow in the dark light button
  • Programmable fan
  • Electric or Gas configurable
  • Room temperature calibration adjustment
  • Separate heating and cooling swing (cycle rate) adjustments
  • Keypad lockout
  • Heating and cooling set point limits
  • 5 minute compressor delay protection (selectable on or off)
  • Filter change indicator(selectable on or off)
  • Simple private label badge system
  • Easy wire color coded terminal blocks
  • Universal sub-base
  • Mounts on wall or junction box
  • 24V power
  • 3 year warranty


Weight0.8 Pounds (lbs)
Length1 Inches (In)
Width4.7 Inches (In)
Height4.6 Inches (In)
Country of OriginCHN
Accuracy1º F
Ambient Temperature Range32°F to 105°F (0°C to 40.5°C)
ApplicationCommercial and Residental
Built In Wi-FiYes
Differential TemperaturePlus or minus 2 degree
Digital-Non ProgrammableYes
Display OptionsLCD, Backlit
Dual Transformer CompatibleYes
Electrical Connection18 to 30 VAC, NEC Class II, 50/60 HZ for Hardwire
Electrical Rating18-30 VAC, NEC Class II
Fan SwitchingYes
MountingDrywall, stud, junction box
Number of HVAC Zones1
Operating Temperature Range31°F to 105°F (-0.5°C to 40.5°C)
Power MethodHardwired
Programmable FanYes
Prop 65No
Removable InterfaceNo
Sensing ElementYes
Stages Cool2
Stages Heat3
Switch ActionRelay
System SwitchingYes
Temperature Range44°F to 90°F (6.6°C to 32.2°C)
Temperature Settings per Day4
Terminal DesignationsRh, Rc, C, Y, Y2, W/E, W2 G, O, B
Voltage24 VAC
Warranty OfferedYes


Equipment Part List

‡Ductless Stock Up and Save offer valid thru May 31, 2019 at participating CE locations. Account must be active and in good standing condition to qualify for terms. Excludes special pricing and all accessories. Special quotes, OEM parts & job pricing excluded. Not valid on previous purchases. Offer cannot be combined with other offers or programs. Management reserves the right to modify or end this promotion at any time without notice. Orders must be placed and taken delivery by May 31, 2019.
Ductless Stock Up and Save