Your browser is not supported. For the best experience, you should upgrade to a modern browser with improved speed and security.

Pro1 IAQ T855i - 5/1/1 Progammable or 7 Day or Non-Programmable Wi-Fi Thermostat, 4H/2C With 8 Square Inch display

Item: T855I
MFR: T855i
What’s the price?
Sign in or register for pricing.
Decrease quantity
Increase quantity

Your Order Templates
Save products for later, or create lists to quickly re-buy items for routine jobs.

Add to Order Template

Inventory At Nearby Branches



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 quick start guide will walk the homeowner through the WI-FI linking procedure.
  • Universal Sub-base - 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 setpoint 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


NamePro1 IAQ T855i - 5/1/1 Progammable or 7 Day or Non-Programmable Wi-Fi Thermostat, 4H/2C With 8 Square Inch display
Gemaire Item NumberT855I
Manufacturer Product NumberT855i
SKU - PIM Number1413810886403
ERP Number347390
Unit of MeasureEA
Weight0.8 Pounds (Lb)
Length1.0 Inches (In)
Width4.7 Inches (In)
Height4.6 Inches (In)
Hazardous MaterialNo
EPA Cert RequiredNo
Country of OriginCHN
Electrical Connection18 to 30 VAC, NEC Class II, 50/60 HZ for Hardwire
Electrical Rating18-30 VAC, NEC Class II
Power MethodHardwired
Batteries IncludedNo
750mV CompatibleYes
Auto ChangeoverYes
Built In Wi-FiYes
Change/Check RemindersYes
Daylight Savings Time ReadyYes
Digital-Non ProgrammableYes
Display OptionsLCD, Backlit
Displays Outdoor TemperatureNo
Heat Pump CompatibleYes
Indoor Remote SensorNo
Low Battery IndicatorYes
Programmable FanYes
Stages Cool2
Stages Heat3
Temperature Settings per Day4
Vacation ModeYes
Battery BackupNo
Accuracy1º F
Sensing ElementYes
Ambient Temperature Range32°F to 105°F (0°C to 40.5°C)
ApplicationCommercial and Residental
Differential TemperaturePlus or minus 2 degree
Dual Transformer CompatibleYes
Fan SwitchingYes
MountingDrywall, stud, junction box
Number of HVAC Zones1
Operating Temperature Range31°F to 105°F (-0.5°C to 40.5°C)
Removable InterfaceNo
Switch ActionRelay
System SwitchingYes
Temperature Range44°F to 90°F (6.6°C to 32.2°C)
Terminal DesignationsRh, Rc, C, Y, Y2, W/E, W2 G, O, B
Warranty Offered3 Year
Energy Star RatedNo
GEM - Case Quantity


Tell Us How We Can Improve Your Shopping Experience - click here!