Emerson 1F86-0244 Thermostat Operation Manual
The Emerson 1F86-0244 is a Blue 2” non-programmable, single-stage thermostat designed for conventional gas, oil, electric, or heat pump systems without auxiliary heat. It features a backlit LCD display, easy push-connect terminals, and precise temperature control. Below are the key specifications and operation instructions.
Key Specifications
- Type: 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: 2 AA alkaline batteries (Duracell or Energizer recommended)
- Hardwired: 20-30 VAC, NEC Class II, 50/60 Hz with common (C) wire
- Electrical Rating:
- Terminal Load: 0.05 to 1.0 A per terminal, 1.5 A max combined
- Rated Differentials:
- Heat (@ 6°F/Hr): Fast 0.5°F, Medium 0.75°F, Slow 1.9°F
- Cool (@ 6°F/Hr): Fast 0.9°F, Medium 1.2°F, Slow 1.7°F
- Setpoint Range: 45°F to 90°F (7°C to 32°C)
- Display: Backlit LCD display (2 square inches)
- Operating Conditions:
- Ambient: 32°F to 105°F (0°C to 41°C)
- Humidity: 0% to 90% non-condensing
- Shipping: -4°F to 150°F (-20°C to 65°C)
- Dimensions: 3-13/16” H x 5-3/8” W x 1-1/4” D
- Features:
- Backlit display for low-light viewing
- Adjustable temperature display calibration (±4°F)
- Compressor protection (up to 5-minute delay)
- Filter change reminder (0 to 1950 hours, adjustable)
- Easy push-connect color-coded terminals
- Cool Savings feature for energy efficiency during peak A/C demand
- Fossil fuel or electric heat compatibility
- 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 “LO BATTERY” appears (approximately every 2 years). If less than two months of battery life remain, the setpoint temperature may offset by 10°F (cooler in Heat mode, warmer in Cool mode); reset manually with up/down arrows.
2. Power On: If hardwired, ensure 20-30 VAC is supplied via the C terminal. The display should show the home screen. If battery-powered, “LO BATTERY” displays when power is low.
3. Configure System:
- Locate the GAS/ELECTRIC switch on the back of the thermostat (default: GAS). Set to ELECTRIC for systems requiring the thermostat to control the fan during heating (e.g., electric heat or heat pumps).
- Locate the O/B switch (default: O). Set to O for heat pumps energizing the changeover relay in COOL, or B for energizing in HEAT.
- Access CONFIGURATION MENU by pressing SYSTEM to OFF, then holding up/down arrows for 5 seconds.
- Configure options:
- Item 1: Backlight (On or Off).
- Item 2: Select FA (Fast) or SL (Slow) heating cycle rate (FA for gas/oil/electric, SL for hydronic systems).
- Item 3: Temperature display adjustment (±4°F).
- Item 4: Filter replacement time (0 to 1950 hours, 0 to disable).
- Item 5: Temperature display (°F or °C).
- Exit by pressing RUN or waiting for the display to return to normal.
Operating the Thermostat
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 with heating/cooling) or ON (continuous).
4. Verify Operation:
- In HEAT mode, set temperature 1°F above room temperature; a soft click indicates operation, and “Heat On” should display.
- In COOL mode, set temperature 1°F below room temperature; a snowflake icon may flash for up to 5 minutes due to compressor delay, then “Cool On” displays. Do not operate cooling if outdoor temperature is below 50°F to prevent compressor damage.
Temperature Display Adjustment
1. Access CONFIGURATION MENU (SYSTEM to OFF, hold up/down arrows for 5 seconds).
2. Navigate to Item 3 (Temperature Display Adjustment).
3. Use up/down arrows to adjust the displayed temperature by ±4°F to match the actual room temperature.
4. Press RUN to save and exit.
Note: Use a separate thermometer for calibration. Relocate the thermostat if near drafts, heat sources, or exterior walls.
Troubleshooting
- No Display: Check battery polarity or replace batteries. Verify C wire connection for hardwired setups. Reset by pressing up/down arrows and moving SYSTEM switch from OFF to HEAT/COOL for approximately 10 seconds 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 snowflake icon). Verify wiring and O/B switch setting for heat pumps. Contact a heating/cooling service person if no click is heard.
- Fan Runs Continuously: Set FAN to AUTO. Verify SYSTEM is not in AUTO mode if only heating or cooling is desired.
- Inaccurate Temperature: Calibrate in CONFIGURATION MENU (Item 3). Ensure thermostat is not near drafts, heat sources, or exterior walls.
- “FILTER” Displayed: Indicates filter replacement needed. Clear by pressing up/down arrows simultaneously in CONFIGURATION MENU (Item 4).
- “LO BATTERY” Persists After Replacement: Inspect battery contacts for corrosion and clean with a pencil eraser. Perform a reset (up/down arrows and SYSTEM switch to HEAT/COOL for 10 seconds). If issue persists, the thermostat may be faulty.
- Erratic Operation: A voltage spike or static discharge may cause issues. Reset by pressing up/down arrows and moving SYSTEM switch from OFF to HEAT/COOL for 10 seconds.
Installation Instructions
Warning: Thermostat installation and all components shall conform to Class II circuits per the NEC code. Do not use with line voltage systems; verify wiring with a qualified technician if unsure.
Remove Old Thermostat
- Turn off power at the main fuse or circuit breaker until installation is complete.
- Remove the front cover of the old thermostat. With wires attached, remove the wall plate. If it has a mounting plate, remove the thermostat and plate as an assembly.
- Mark wires for terminal identification using labels provided with the new thermostat.
- Disconnect wires one at a time, ensuring they do not fall back into the wall.
Installing New Thermostat
- Gently pull the thermostat cover off the 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 and drill mounting holes. Use plastic screw anchors if existing holes are too large.
- Fasten base snugly to the wall using two mounting screws. Leveling is for appearance only and does not affect operation.
- Connect wires to the terminal block using the appropriate wiring schematic (see Wiring section).
- Push excess wire into the wall and plug the hole with fire-resistant material (e.g., fiberglass insulation) to prevent drafts.
- Snap the thermostat onto the base carefully.
Battery Location
- Includes 2 AA alkaline batteries with a battery tag to prevent power drainage. Remove the tag to engage batteries.
- Replace batteries when “LO BATTERY” appears or before leaving the home unoccupied for over 3 months. Use premium brand AA alkaline batteries (e.g., Duracell or Energizer).
- Install batteries along the top of the rear compartment, ensuring positive (+) ends are oriented correctly.
Wiring and Terminal Functions
Refer to the equipment manufacturer’s instructions for specific wiring. The following table describes typical terminal functions:
Terminal | Function |
RC | Cooling power (24 VAC) |
RH | Heating power (24 VAC) |
C | Common wire for 24 VAC power from transformer |
W | Heat relay |
Y | Compressor contactor (cooling) |
G | Fan relay |
O/B | Heat pump changeover valve (O: cool, B: heat) |
Note: For two-wire heat-only systems, connect one wire to RH and the other to W. For single-transformer systems, jumper RC and RH. For heat pumps, set O/B switch to “O” (cool) or “B” (heat) as required by the system. Do not exceed specified voltage ratings.
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