White Rodgers 1E50N-303 User Manual

The White Rodgers 1E50N-303 is a simple non-programmable mechanical thermostat for standard heat only systems, including electric furnace, heat pump (no aux or emergency heat), gas or oil heat, and millivolt heat only systems. It features a vertical design, adjustable heat anticipator (0.15 to 1.2 amps), and temperature range of 45°F to 90°F. Below are the key specifications, installation, operation, and troubleshooting instructions.

1. Preparations 2. Description 3. Precautions 4. Specifications 5. Installation 5.1 Wiring Diagrams 6. Check Operation 6.1 Fan Operation 6.2 Heating System 6.3 Emergency System 6.4 Cooling System 7. Operating Features 8. Programming 9. Installer Configuration 10. Troubleshooting

Preparations

Assemble tools required: power drill, flat blade screwdriver, wire cutter/stripper, level. Failure to follow and read all instructions carefully before installing or operating this control could cause personal injury and/or property damage.

WARNING! Failure to read and follow all instructions carefully before installing or operating this control could cause personal injury and/or property damage. Save these instructions.

Description

The thermostat replaces standard heat only systems including electric furnace, heat pump (no aux or emergency heat), gas or oil heat, and millivolt heat only systems. It features a vertical design with captive screws for mounting.

Applications: Standard Heat Only Systems: Electric Furnace, Heat Pump (No Aux or Emergency Heat), Gas or Oil Heat, Millivolt Heat Only Systems.

Precautions

CAUTION! To prevent electrical shock and/or equipment damage, disconnect electrical power to the system at the main fuse or circuit breaker until installation is complete.

Specifications

Removing Old Thermostat

A standard thermostat consists of three basic parts: A) The cover (snap-on or hinge type); B) The base (loosened by turning all captive screws); C) The switching subbase (removed by unscrewing mounting screws). Before removing wires from old thermostat's switching subbase, label each wire with the terminal designation it was removed from. Make a note of the heat anticipator setting on the old thermostat (0.2, 0.4, 0.8, etc.) for reference in step 5.

Installation

Do not use on circuits exceeding specified voltage. Higher voltage will damage control and could cause shock or fire hazard. Do not short out terminals on gas valve or primary control to test. Short or incorrect wiring will damage thermostat and could cause personal injury and/or property damage. Thermostat installation and all components of the system shall conform to Class II circuits per the NEC code. A) Remove base from subbase or wallplate by loosening the screws on the base. B) Mount switching subbase or wallplate using the screws provided. C) Attach wires to appropriate terminals: Two wire systems (Heat Only) - attach one wire to RH and one to W. D) Mount Thermostat Base: Gently push excess wire back into the wall opening and plug hole with a fire-resistant material such as fiberglass insulation to prevent drafts. Mount the thermostat base to the subbase or wallplate using the three captive screws on the thermostat base. Tighten the screws securely.

Wiring Diagrams

Terminal Designations: RH (hot), W (heat).

Two Wire Systems (Heat Only): Attach one wire to RH and one to W.

CAUTION! Take care when securing and routing wires so they do not short to adjacent terminals or rear of thermostat. Personal injury and/or property damage may occur.

Check Operation

This thermostat is easy to operate. After power is turned on, raise temperature above room temperature to turn the heating system on. Lower temperature below room temperature to turn heating system off.

Fan Operation

Not applicable; heat only thermostat without fan control.

Heating System

  1. Turn thermostat knob above room temperature; heating system turns on.
  2. Turn knob below room temperature; heating system turns off.

Emergency System

Not applicable for heat only systems.

Cooling System

Not applicable; heat only thermostat.

Operating Features

Programming

Non-programmable mechanical thermostat. Adjust temperature using knob.

Installer Configuration

Set heat anticipator to match the setting of your old thermostat or the current rating stamped on your main heating control (0.15 to 1.2 amps). Turn the contact arm to the appropriate setting. For millivolt operation, turn the contact arm to the Millivolt Link position.

Anticipator SettingCurrent Rating
.20.15-0.3A
.40.3-0.6A
.80.6-1.2A
MMillivolt

Troubleshooting

SymptomPossible CauseCorrective Action
Heating system will not turn onAnticipator set too high, thermostat not level, wiring error.Lower anticipator setting, level thermostat, check wiring.
Heating system cycles too fastAnticipator set too low.Increase anticipator setting.
Heating system cycles too slowAnticipator set too high.Decrease anticipator setting.
Heating system does not turn offAnticipator set too low, wiring short.Increase anticipator setting, check wiring.
Temperature reading inaccurateImproper location, drafts.Relocate thermostat, seal drafts.
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