Emerson 1E78-140 Non-Programmable Heat Only Thermostat User Manual

Package Contents

• Emerson 1E78-140 Non-Programmable Thermostat
• Wallplate
• 3 AAA Batteries
• Mounting Screws and Anchors
• User Manual

Installation

1. Turn off power to the heating system at the main power panel to avoid electrical shock.
2. Remove the old thermostat, but leave the wallplate with wires attached.
3. Label the existing wires with the provided wire labels before removing them from the old thermostat.
4. Remove the wallplate from the old thermostat and mount the new wallplate using the provided screws and anchors.
5. Connect the labeled wires to the corresponding terminals on the new thermostat. (For a two-wire system, connect the red wire to the RH terminal and the white wire to the W terminal)
6. Install the 3 AAA batteries included in the package.
7. Attach the thermostat to the wallplate by aligning the top edge and then snapping the bottom edge into place.
8. Turn the power back on to the heating system.

Operation

1. Set the system switch to "HEAT" mode.
2. Use the UP and DOWN arrow buttons to adjust the desired temperature.
3. The thermostat will control the heating system to maintain the set temperature.

Activating the Backlight

1. Press and hold the UP and DOWN arrow buttons simultaneously until the display starts blinking.
2. Press the UP arrow button to change the display to "ON".
3. Move the system switch from "HEAT" to "OFF" and then back to "HEAT" to save the setting.
4. The backlight will now turn on every time a button is pressed and turn off automatically after a few seconds.

Troubleshooting Tips

• If the thermostat is not functioning, ensure that the batteries are installed correctly and have sufficient power.
• Verify that the wires are connected to the correct terminals.
• Ensure the heating system is turned on at the main power panel.
• If the thermostat is not maintaining the correct temperature, check if the thermostat is installed in a location with proper airflow and away from direct sunlight or drafts.

Frequently Asked Questions

Can this thermostat be used with a baseboard heater?

Yes, the Emerson 1E78-140 Non-Programmable Thermostat is compatible with single-stage heat-only systems, including baseboard heaters.

How do I change the thermostat from Fahrenheit to Celsius?

To change the temperature display from Fahrenheit to Celsius, locate the jumper wire labeled "W905" on the back of the thermostat and cut it. The display will now show temperature in Celsius.

Is this thermostat compatible with a millivolt system?

Yes, the Emerson 1E78-140 Non-Programmable Thermostat is compatible with millivolt systems. For a two-wire millivolt system, connect the red wire to the RH terminal and the white wire to the W terminal.

Can I use this thermostat with a gas fireplace?

Yes, the Emerson 1E78-140 Non-Programmable Thermostat can be used with a gas fireplace. Replace the existing on/off wall switch with this thermostat by connecting the red wire to the RH terminal and the white wire to the W terminal.

How do I set the thermostat for use with a hydronic heating system?

For use with a hydronic heating system, locate the jumper wire labeled "W905" on the back of the thermostat and cut it. This will ensure longer heat cycles for hydronic systems.

Product: Emerson 1E78-140 Non-Programmable Heat Only Thermostat for Single-Stage Systems White - Automotive Parts & Accessories

Specifications:
- Easy-to-read digital display with backlight
- Non-programmable thermostat
- Compatible with single stage heat only systems
- Precision control of plus/minus 1 degree F
- Vertical profile. Thermostat Compatibility-Baseboard Heater
- Brand: Emerson Thermostats
- Manufacturer: White-Rodgers
- Model Number: 1E78-140
- Manufacturer: White-Rodgers
- Part Number: 1E78-140
- Item Weight: 1.6 ounces
- Product Dimensions: 1.13 x 3.19 x 5.31 inches
- Country of Origin: China
- Item model number: 1E78-140
- Batteries: 3 AAA batteries required.
- Is Discontinued By Manufacturer: No
- Color: White
- Shape: Curved
- Voltage: 24 Volts
- Wattage: 45
- Item Package Quantity: 1
- Display Style: Digital
- Included Components: White-Rodgers 1E78-140 Thermostat Wall Dig Heat Only
- Batteries Included?: Yes
- Batteries Required?: No
- Battery Cell Type: Alkaline
- ASIN: B00204WWGE
- Customer Reviews: 4.5 out of 5 stars 2,811 ratings 4.5 out of 5 stars
- Best Sellers Rank: #13,236 in Tools & Home Improvement
- Domestic Shipping: Item can be shipped within U.S.
- International Shipping: This item can be shipped to select countries outside of the U.S.

FAQ:

Q1. Does the display light up as shown in the description? That would make it easier to read.
A1. Yes, the thermostat has a backlight. Press up and down arrows at the same time for 2 seconds to activate it.

Q2. Can I use it in an RV with a 12 (2 wire) volt system?
A2. If it is just for heat only, you can use it. However, if you have a duct system with AC and heat, you cannot use it.

Q3. Will this work with a Cozy gas wall heater that uses 2 wires?
A3. Yes, it will work with any 2-wire thermostat.

Q4. Will this thermostat work with a suburban furnace in a camping trailer?
A4. Yes, it will control the furnace but not the AC if they are on the same thermostat.

Q5. Why does it need a battery? What happens when the batteries croak? Will it stop the furnace from running?
A5. The batteries run the display and the relay on the gas valve. If the batteries go completely down, the heater will not work. The display has a low battery warning so you can replace them before heater quits working.

Q6. With what voltage is this thermostat set to operate?
A6. It operates on 0v(millivolt) to 24v. The 2 AAA batteries are there to provide current to the thermostat display and inner circuitry.

Q7. Mine shows room temp 5 degrees too high, can it be adjusted?
A7. Yes, it can be adjusted by +/-3 degrees. Directions can be found on the third page of the manual under TEMPERATURE DISPLAY ADJUSTMENT.

Overall, the Emerson 1E78-140 Non-Programmable Heat Only Thermostat for Single-Stage Systems is an easy-to-use and reliable product for controlling heating systems. The digital display with backlight makes it easy to read and adjust temperature settings. It is compatible with single-stage heat only systems and provides precision control of plus/minus 1 degree F. The thermostat requires 3 AAA batteries to operate and can be adjusted for temperature display accuracy. It is a great choice for RVs, camping trailers, and gas fireplaces.