White Rodgers 1F90W-51 User Manual

The White Rodgers 1F90W-51 is a non-programmable electronic digital thermostat with wireless remote indoor sensor for single-stage heating and cooling systems, including gas, oil, electric, and single-stage heat pumps. It features precise temperature control, filter timer, wireless sensor up to 200 ft range, and easy operation with large display. Powered by 24 VAC system; compatible with systems up to 1.5A total load. Below are the key specifications, installation, operation, and troubleshooting instructions.

Preparations

Assemble tools: hand or power drill with 3/16 inch drill bit (if needed), flat blade screwdriver, wire cutter/stripper, level. Shut off electricity at main fuse box until installation complete. Label wires before disconnecting. This thermostat is for 24V systems only; not for line voltage. Install thermostat and sensor away from drafts, direct sunlight, or heat sources for accurate sensing. Sensor location: 5 ft above floor, interior wall, avoid windows/doors/registers.

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 provides precise electronic control with large, easy-to-read display. Features up/down arrows for setpoint adjustment, SYSTEM switch (HEAT/OFF/COOL/AUTO), FAN switch (ON/AUTO), O/B for heat pumps. Display shows current temperature (local or remote/average) and setpoint. Includes wireless remote indoor sensor (F145W-01) for extended range up to 200 ft. Supports single-stage heat/cool, heat-only, cool-only, and single-stage heat pumps.

Applications: Gas/Oil/Electric Heat: Yes; Heat Pump Single Stage: Yes; Heat Only: Yes; Cool Only: Yes; Millivolt: No; Hydronic: Yes.

Precautions

CAUTION! To prevent electrical shock/equipment damage, disconnect power at main fuse/circuit breaker until installation complete. Label wires prior to disconnection.

WARNING! Do not use on circuits exceeding 30 VAC 50/60 Hz (1.5A max total); higher voltage damages control/causes shock/fire. Do not short terminals to test; incorrect wiring causes injury/property damage. Conform to NEC Class II circuits. Do not operate cooling below 50°F (compressor damage).

ATTENTION! This product does not contain mercury but may replace one that does. Dispose properly; refer to recycling resources.

Specifications

• Electrical: 20-30 VAC 50/60 Hz, NEC Class II; Terminal Load 1.5A max total (all terminals).
• Setpoint Range: 45°F to 90°F (7°C to 32°C).
• Operating Ambient: 32°F to 105°F (0°C to 41°C).
• Humidity: 90% non-condensing max.
• Shipping: -40°F to 150°F (-40°C to 65°C).
• Dimensions: Thermostat 3-1/2”H x 5-1/2”W x 1-1/8”D; Sensor 2-3/4”H x 4-1/2”W x 7/8”D.
• Wireless: 418 MHz, up to 200 ft range, battery-powered (2 AA).
• Other: Compressor lockout 5 min; Filter timer adjustable.

Removing Old Thermostat

A standard heat/cool thermostat consists of three basic parts: 1) Cover; 2) Base; 3) Subbase. Label each wire with terminal designation before disconnecting. Disconnect wires one at a time; do not let fall into wall.

Installation

Remove old thermostat. Mount new base level on wall, connect wires to terminals. For single transformer systems, install red jumper between RH and RC. Push excess wire into wall, secure base, attach thermostat body. Power up and configure. For sensor: Mount on wall or table, insert batteries, pair with thermostat (hold button until signal).

Wiring Diagrams

Terminal Designations: RH/RC (power), W (heat), Y (cool/compressor), G (fan), O/B (changeover for heat pump).

Single Stage Heat/Cool: RH to hot, RC to hot (jumper RH-RC), W to heat relay, Y to compressor, G to fan.

Heat Only: Omit Y.

Cool Only: Omit W.

Heat Pump Single Stage: Y to compressor, O/B to changeover (O for cool, B for heat), W to aux if applicable.

CAUTION! RED jumper wire must be connected between RH and RC for single transformer systems.

Wireless Sensor Installation

Mount sensor 5 ft above floor, away from heat sources. Insert 2 AA batteries (positive to right). Press and hold sync button on sensor until LED flashes. On thermostat, enter config menu to pair (select remote sensor option). Signal strength indicator shows bars on display.

Check Operation

Restore power. Set SYSTEM to HEAT/COOL, FAN to ON/AUTO, adjust setpoint to test. Verify sensor signal.

Fan Operation

1. FAN ON: Blower runs continuously.
2. FAN AUTO: Blower runs on call for heat/cool.

Heating System

1. SYSTEM HEAT.
2. Setpoint above room temp: Heat activates.
3. Setpoint below: Heat stops.

Cooling System

CAUTION! Do not operate below 50°F.

1. SYSTEM COOL.
2. Setpoint below room temp: Cool activates (5-min delay first time).
3. Setpoint above: Cool stops.

Operating Features

• Home Screen: LCD shows current room temperature (local, remote, or average) and setpoint; signal strength bars.
• Key Features: Backlit display, filter change indicator, compressor protection, auto changeover in AUTO mode (3°F separation), wireless sensor selection (local/remote/average).
• Compressor Protection: 5-min lockout.
• Range Limits: Heat 45-90°F, Cool 45-90°F.

Installer Configuration

Remove cover, press and hold UP and DOWN arrows simultaneously for 5 seconds to enter setup. Use UP/DOWN to adjust, press HOLD to advance. Additional menu for wireless: Sensor mode (0=local, 1=remote, 2=average), calibration ±3°F.

Troubleshooting