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EMERSON Low Voltage Thermostat: Heat Only, RH/W, Auto, On-Off, On-Off/Auto, Vertical - Digital Thermostats
EMERSONDigital Thermostats

EMERSON Low Voltage Thermostat: Heat Only, RH/W, Auto, On-Off, On-Off/Auto, Vertical

The EMERSON Low Voltage Thermostat: Heat Only (MPN 1E78-140) is a digital thermostat designed for heat-only applications. It operates on 20V AC with a slide switch control, auto fan setting, and on-off system…

SKU 3G-OTH-70474

Brand
EMERSON
Item
Low Voltage Thermostat: Heat Only, RH/W, Auto, On-Off, On-Off/Auto, Vertical
Category
Digital Thermostats
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Technical Specifications

EMERSON
Manufacturer Part Number
1E78-140
Type
RH/W, Auto, On-Off, On-Off/Auto, Vertical, Rectangle
Shape
Rectangle
Voltage
20V AC
Digit Size
Standard
Application
Heat Only
Control Type
Slide Switch
Fan Settings
Auto
Key Features
Selectable Celsius or Fahrenheit Temperature Display
System Settings
On-Off
Mounting Direction
Vertical
Terminal Designations
RH
Temperature Differential
0.8° to 1.5°F
Temperature Control Range
45° to 99°F
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EMERSON Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The EMERSON Low Voltage Thermostat: Heat Only (MPN 1E78-140) is a digital thermostat designed for heat-only applications. It operates on 20V AC with a slide switch control, auto fan setting, and on-off system settings, featuring a selectable Celsius or Fahrenheit temperature display. The thermostat has a temperature differential of 0.8° to 1.5°F and a temperature control range of 45° to 99°F, with terminal designations RH and vertical mounting orientation.

Used in

Common applications for EMERSON
Commercial refrigeration — Emerson single-stage electronic control (SKU 44R204) for walk-in coolers and freezers
HVAC system retrofits — Emerson low-voltage digital thermostat (SKU 3MY10) for heat or cool control in office buildings
Industrial process temperature — Emerson line-voltage mechanical thermostat (SKU 2E399) for equipment heating in manufacturing
Residential heating — Emerson analog heat-only thermostat (SKU 3MU96) for baseboard or radiant systems
Heat pump installations — Emerson standard thermostat (SKU 42PD14) for 1H/1C heat pump systems in commercial spaces
Cooling-only applications — Emerson mechanical cool-only thermostat (SKU 3MU97) for server rooms or storage areas

EMERSON Products

3G Electric supplies EMERSON digital thermostats. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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EMERSON Low Voltage Thermostat: Heat or Cool, Manual, C/G/O/B/R/W/Terminal Designations, Auto-On (MPN 1F86EZ-0251). Key specifications — Application: Heat or Cool; Key Features: Change Filter Reminders; Temperature Differential: 0.6° to 1.7°F; Voltage: 20V AC; Terminal Designations: C; System Settings: Cool-Heat-Off; Temperature Control Range: 45° to 99°F; Changeover Type: Manual.
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EMERSON Low Voltage Thermostat: Heat or Cool, Manual, C/G/O/B/R/W/Terminal Designations, Auto-On (MPN 1F86EZ-0251). Key specifications — Application: Heat or Cool; Key Features: Change Filter Reminders; Temperature Differential: 0.6° to 1.7°F; Voltage: 20V AC; Terminal Designations: C; System Settings: Cool-Heat-Off; Temperature Control Range: 45° to 99°F; Changeover Type: Manual.