Emerson 1F87U-42WF Sensi Smart Thermostat Operation Manual

The Emerson 1F87U-42WF Sensi Smart Thermostat is a Wi-Fi-enabled thermostat designed for conventional heating and cooling systems, heat pumps, and dual fuel systems. It features remote app control, geofencing, and flexible scheduling for energy savings. Below are the key specifications and operation instructions.

Key Specifications

• Type: Programmable Wi-Fi thermostat
• Compatibility:
  • Conventional heating and cooling
  • Heat only or cool only (2 wire)
  • Heat pumps
  • Not compatible with millivolt systems, communicating systems, line voltage systems
• Power Source:
  • Hardwired: 20-30 VAC, NEC Class II, 50/60 Hz with common (C) wire required for heat only, cool only, heat pumps
  • External 24 VAC Transformer option
• Electrical Rating:
  • Terminal Load: 1.5 A per terminal, 2.5 A max combined
  • Rated Differentials: Heat (0.6°F/1.5°F), Cool (1.2°F/1.7°F), Heat Pump (1.2°F/1.7°F)
• Display: Touchscreen
• Temperature Range: Setpoint 45°F to 99°F (7°C to 37°C)
• Operating Conditions:
  • Ambient: 32°F to 105°F (0°C to 41°C)
  • Humidity: 90% non-condensing max
  • Shipping: -40°F to 150°F (-40°C to 65°C)
• Dimensions: 3.25” H x 5.13” W x 1” D
• Features:
  • Remote app control
  • Geofencing
  • Flexible scheduling
  • High/low temperature alerts
  • Smart home integration (Amazon Alexa, Google Assistant, Apple HomeKit, SmartThings, Wink)
  • Sleep mode, nightlight
  • Humidity display
  • Multi-thermostat control
  • Auto changeover
  • Humidity control
• Thermostat Configuration Options:
  • Single Stage (SS1): Gas, Oil, Electric, Heat Only, Cool Only or Heat/Cool Systems - Maximum Stages Heat/Cool: 1/1
  • Multi Stage (MS2): Gas, Oil, Electric - Maximum Stages Heat/Cool: 2/2
  • Heat Pump (HP1/HP2): Single or Multi-Stage Compressor - Maximum Stages Heat/Cool: 4/2

Operation Instructions

Initial Setup

1. Download Sensi App: The Sensi Touch is Wi-Fi enabled. Download the Sensi app to install and configure.
2. Power On: Ensure 20-30 VAC is supplied via the C wire. The touchscreen should display the home screen.
3. Configure System:

• Use the Sensi app to configure system type, fan settings, and options.
• Press MENU on thermostat for on-device configurations like sleep mode, backglow, home screen content, schedule, Wi-Fi, about thermostat, advanced setup, setup HVAC, fan mode options, humidify, and dehumidify.
• Exit by pressing back arrow or saving changes.

Setting the Clock and Day

1. When Wi-Fi is connected, date and time are automatically set based on time zone.
2. When Wi-Fi is off, select date or time to edit.
3. Adjust using up/down arrows.
4. Press “Save” when done. Use back arrow to return to previous screen.

Operating in Non-Programmable Mode

1. Select Mode: Press Mode button to switch between Heat, Cool, Off, Aux, or Auto.
2. Adjust Temperature: Use up/down arrows to set desired temperature.
3. Fan Control: Press Fan to switch between Auto (thermostat-controlled) or On (continuous).
4. Manual Override: Turn Schedule "Off" to hold one temperature indefinitely.

Operating in Programmable Mode

1. Factory Schedule: Pre-programmed with energy-saving settings.
2. Custom Schedule:

• When Wi-Fi connected, program schedule via Sensi app.
• When Wi-Fi off, go to Menu, select Schedule, toggle "On," select day grouping (weekdays or weekend), edit set points, save each, use back arrow to navigate.

3. Temporary Override: With Schedule "On," use up/down arrows to temporarily change temperature, holds for at least two hours or until next scheduled set point.
4. Permanent Hold: Turn Schedule "Off" to hold one temperature until Schedule is turned "On" or set point adjusted.
5. Disable Programming: Turn Schedule "Off" in Menu.

Advanced Features

1. Sleep Mode: Toggle to display room temperature when screen is in sleep mode.
2. Nightlight: Switch on thermostat base illuminates wiring during installation. Turn base switch "Off" after installation to enable toggling via Menu for area lighting.
3. Home Screen Content: Toggle display of current time, humidity, or temperature scale (Fahrenheit/Celsius).
4. Wi-Fi: Connect via Sensi app using "Set up a new network." Can be turned on/off from Menu.
5. About Thermostat: Displays model number, MAC ID, build date, firmware version, technical support, and factory reset button (resets all settings except HVAC equipment settings and clears HomeKit pairing).
6. Advanced Setup: Additional accessories like humidifier (wired to Y2/* terminal) and dehumidifier (wired to W2/* terminal). System compatibility for humidity: heat only (humidifier only), cool only (dehumidifier only), 1 stage heat/1 stage cool (both), with notes for 2 stage systems.

Troubleshooting

• No Display: Check wiring and C wire connection. Reset by removing thermostat from wall for 2 minutes.
  
• No Heat/Cool: Ensure SYSTEM is set to HEAT/COOL, setpoint is above/below room temperature, and wiring is correct. Check for compressor delay. Verify system compatibility in Sensi app.
  
• System Runs Continuously: Set FAN to AUTO. Verify setpoint settings. Check for shorted wires.
  
• Inaccurate Temperature: Relocate thermostat away from drafts/heat sources.
  
• Wi-Fi Connection Issues: Ensure within router range. Reconnect via Sensi app.
  
• Humidity Control Issues: Verify accessory wiring and system compatibility. For 2 stage systems, second stage must be enabled on furnace/air handler board for dehumidification.

Installation Instructions

Warning: Thermostat installation and all components shall conform to Class II circuits per the NEC code. Disconnect power at the main fuse or circuit breaker before installation to prevent electrical shock or equipment damage.

Remove Old Thermostat

• Before removing wires, mark wires for terminal identification to ensure proper connections to the new thermostat.

Installing New Thermostat

1. Pull the thermostat body off the thermostat base. Do not force or pry to avoid damage.
2. Place base over the hole in the wall and mark mounting hole locations using the base as a template.
3. Move base out of the way, drill mounting holes. Use plastic screw anchors if existing holes are too large.
4. Fasten base snugly to the wall using mounting holes and two mounting screws. Leveling is for appearance only and does not affect operation.
5. Connect wires to the terminal block on the base using the appropriate wiring schematic.
6. Push excess wire into the wall and plug the hole with fire-resistant material (e.g., fiberglass insulation) to prevent drafts.
7. Carefully line the thermostat up with the base and snap into place.

Battery Location

• No batteries required as it uses hardwired power.

Power Stealing Switches

Not applicable; requires C wire for power.

Thermostat Power Method	Switch Position/Description
Hardwired with C wire	Thermostat runs on power from transformer.

Caution: No power stealing; C wire is mandatory.