Emerson 1F75C-11PR Thermostat Operation Manual

The Emerson 1F75C-11PR is a 70 Series Programmable Thermostat designed for single-stage heating and cooling systems, including conventional gas, oil, electric, or heat pump systems without auxiliary heat. It offers 5+1+1 day programming, a backlit display, and simple operation for precise temperature control. Below are the key specifications and operation instructions.

1. Key Specifications 2. Operation Instructions 2.1. Initial Setup 2.2. Setting the Clock and Day 2.3. Operating in Non-Programmable Mode 2.4. Operating in Programmable Mode 2.5. Advanced Features 2.6. Troubleshooting 3. Installation Instructions 3.1. Remove Old Thermostat 3.2. Installing New Thermostat 3.3. Battery Location 3.4. Power Stealing Switches

Key Specifications

Type: Programmable (5+1+1 day) or non-programmable, single-stage thermostat
Compatibility:
- Conventional systems (gas, oil, electric, millivolt, 24V)
- Heat pump systems (air source or geothermal) without auxiliary heat
- Heat only, cool only, or heat/cool systems
- Not compatible with systems exceeding 30 VAC or electric baseboard heat
Power Source:
- Battery: mV to 30 VAC, NEC Class II, 50/60 Hz (2 AA alkaline batteries, Duracell or Energizer recommended)
- Hardwired: 20-30 VAC, NEC Class II, 50/60 Hz with common (C) wire
- Power Stealing Assist for systems without C wire
Electrical Rating:
- Terminal Load: 1.0 A per terminal, 1.5 A max combined
- Rated Differentials (@ 6°F/Hr):
  - Heat: Fast 0.5°F, Medium 0.75°F, Slow 1.9°F
  - Cool: Fast 0.9°F, Medium 1.2°F, Slow 1.7°F
- Setpoint Range: 45°F to 99°F (7°C to 37°C)
Display: Backlit LCD display, adjustable ±5°F
Operating Conditions:
- Ambient: 32°F to 105°F (0°C to 41°C)
- Humidity: 90% non-condensing max
- Shipping: -20°F to 150°F (-29°C to 65°C)
Dimensions: 3-3/4” H x 6” W x 1-1/8” D
Features:
- 5+1+1 day programmable scheduling (Mon-Fri, Sat, Sun)
- Automatic heat/cool changeover
- Adjustable temperature display calibration
- Compressor protection (up to 5-minute delay)
- Optional wall cover-up plate (F61-2663, 6-3/4” W x 4-1/2” H)
- Keypad lockout option
- Energy-saving pre-programmed schedules
Thermostat Configuration Options:
- Conventional Gas, Oil, Electric (mV and 24V), Heat Only, Cool Only, or Heat/Cool Systems - Maximum Stages Heat/Cool: 1/1
- Heat Pump (Air Source or Geothermal) without Aux. Heat - Maximum Stages Heat/Cool: 1/1

Operation Instructions

Initial Setup

1. Insert Batteries: Install 2 AA alkaline batteries in the rear compartment, removing the battery tag to activate. Replace when the battery indicator shows low (approximately every 2 years).
2. Power On: If hardwired, ensure 20-30 VAC is supplied via the C terminal. The display should show the home screen.
3. Configure System:

Press and hold MENU for 8 seconds to access INSTALLER MENU (item 30).
Select system type (Conventional or Heat Pump), heat cycle rate (Fast, Medium, Slow), compressor delay (item 50), and O/B setting for heat pumps (O: cool, B: heat).
Exit by pressing RUN or waiting for the display to return to normal.

Setting the Clock and Day

1. Press MENU, then select SET TIME.
2. Use up/down arrows to adjust hours, minutes, and AM/PM.
3. Select SET DAY and adjust to the current day of the week.
4. Press RUN to save and exit.

Operating in Non-Programmable Mode

1. Select Mode: Press SYSTEM to choose HEAT, COOL, AUTO, or OFF.
2. Adjust Temperature: Press up/down arrows to set the desired temperature.
3. Fan Control: Press FAN to select AUTO (runs only when heating/cooling) or ON (continuous).
4. Manual Override: Press HOLD and adjust temperature to bypass any schedule until RUN is pressed.
5. Disable Programming: In INSTALLER MENU (item 30), set item 01 to 0 (non-programmable).

Operating in Programmable Mode

1. Factory Schedule: The thermostat is pre-programmed with energy-saving settings (e.g., Heat: 70°F day, 62°F night; Cool: 78°F day, 82°F night). Press RUN to use defaults.
2. Custom Schedule:

Press MENU, then SET SCHEDULE, and select HEAT or COOL.
Choose 5+1+1 (Mon-Fri, Sat, Sun).
Set times/temperatures for Wake, Leave, Return, Sleep periods for each day/group.
Save by pressing RUN.

3. Temporary Override: Press up/down arrows to adjust temperature temporarily until the next period.
4. Permanent Hold: Press HOLD and adjust temperature to maintain it until RUN is pressed.
5. Disable Programming: Press MENU, hold INSTALLER CONFIG for 8 seconds, and set item 01 to 0 (non-programmable).

Advanced Features

1. Compressor Protection: Automatically delays compressor restart (up to 5 minutes) to prevent damage, indicated by a flashing setpoint.
2. Keypad Lockout: Enable in INSTALLER MENU (item 30) to restrict access; unlock by pressing MENU and RUN simultaneously for 5 seconds.
3. Temperature Limit Setting: Set maximum/minimum temperature limits in INSTALLER MENU to restrict setpoint adjustments.
4. Energy-Saving Schedule: Pre-programmed settings optimize energy use; customize as needed in SET SCHEDULE.

Troubleshooting

No Display: Check battery polarity or replace with fresh AA alkaline batteries. Verify C wire connection for hardwired setups. Reset by removing batteries for 2 minutes or pressing up/down arrows and SYSTEM switch from OFF to HEAT simultaneously until the display blanks.
No Heat/Cool: Ensure SYSTEM is set to HEAT/COOL, setpoint is above/below room temperature, and circuit breaker is on. Check for compressor delay (up to 5 minutes, indicated by flashing setpoint). Verify wiring and O/B setting for heat pumps. If no response, test system by connecting R, G, and Y wires together.
Furnace Cycles Too Often: In INSTALLER MENU (item 30), adjust heat cycle rate to MEDIUM or SLOW to reduce cycling frequency.
Inaccurate Temperature: Calibrate in USER MENU (item 07, ±5°F). Ensure thermostat is placed about 1.5 meters above the floor, away from drafts, heat sources, or exterior walls.
System Runs Continuously: Set SYSTEM to HEAT or COOL (not AUTO) and FAN to AUTO. Verify setpoint settings are reasonable. Check for shorted wires or incorrect wiring.
Erratic Operation: Reset by removing batteries for 2 minutes or pressing up/down arrows and SYSTEM switch to HEAT simultaneously. If issues persist, contact a professional technician.

Installation Instructions

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

Remove Old Thermostat

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

Installing New Thermostat

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

Battery Location

Includes 2 AA alkaline batteries at the factory with a battery tag to prevent power drainage. Remove the tag to engage batteries.
To replace, set system to OFF, remove thermostat from the wall, and install batteries in the rear along the top. Use premium brand AA alkaline batteries like Duracell or Energizer.
If the home will be unoccupied for over 3 months and the battery level indicator shows low, replace batteries before leaving.

Power Stealing Switches

Leave switches in the “On” position for most systems. Details in the following table:

Thermostat Power Method	Switch Position/Description
Battery Powered, no 24 Volt system	Switches “On”, thermostat runs on batteries.
Hardwired with Battery Back-up, for 24 Volt systems with common connection from transformer to “C” terminal	Switches “On”, thermostat runs on power directly from transformer with battery back-up.
Battery Powered with Power Stealing Assist, for 24 Volt systems with no common connection	Switches “On”, thermostat runs on batteries and supplemental power drawn through heat or cool circuit.

Caution: Power Stealing Assist may cause issues on systems with high impedance electronic modules (e.g., furnace draft inducer motor running with no call for heat, furnace fan not turning off). If incompatible, set switches to “Off” to operate on batteries.