Ruud Furnace Manual

The Ruud Furnace is a high-efficiency heating system designed for residential use, featuring advanced combustion technology, variable-speed blower motors, and smart thermostat compatibility. Available in various models with AFUE ratings up to 98%, it provides reliable heating with energy-saving operation, built-in diagnostics, safety controls, and easy maintenance access. Below are key sections for safety, features, installation, setup, operation, and troubleshooting.

Features at a Glance

Key components: Heat exchanger, blower assembly, gas valve, ignition system, control board, filter access, pressure switches, venting system.

Feature	Description
Heat exchanger	Stainless steel construction for durability and efficiency
Variable-speed blower	Adjusts airflow for optimal comfort and efficiency
Hot surface ignitor	Reliable electronic ignition system
Control board	Microprocessor-based with diagnostic LED
Filter access	Easy-to-replace standard 1-inch or 4-inch filters
Pressure switches	Safety monitoring of venting system
Gas valve	Precise gas flow regulation
Venting options	PVC or ABS pipe compatible
Thermostat connection	Compatible with most 24V systems
Service light	LED indicator for maintenance alerts

Installation

Unpack and inspect contents. Ensure proper location with adequate clearance.

1. Position furnace: Place on stable, level surface with proper clearances (refer to specifications).
2. Connect gas line: Use approved gas piping; pressure test for leaks.
3. Connect electrical: 120V AC power supply; proper grounding required.
4. Install venting: Use approved PVC or ABS piping; maintain proper slope.
5. Connect thermostat: Use 18-gauge thermostat wire; follow wiring diagram.

WARNING! Installation must be performed by qualified HVAC technician. Gas leaks can cause explosion or fire.

First-Time Setup

Power on furnace; follow startup procedure.

1. Check gas supply: Ensure gas valve is open; verify proper pressure.
2. Set thermostat: Place in OFF position during initial setup.
3. Power up: Turn on electrical power; observe control board LED.
4. Test operation: Set thermostat to HEAT mode above room temperature.
5. Verify operation: Listen for proper ignition sequence and airflow.

CAUTION! Ensure proper ventilation and combustion air supply. Test carbon monoxide detectors.

Specifications

• Models: Various sizes from 40,000 to 120,000 BTU
• AFUE Rating: Up to 98% efficiency
• Electrical: 120V AC, 60Hz, 15A circuit
• Gas Type: Natural gas or LP (conversion kit required)
• Blower Motor: Variable-speed ECM
• Heat Exchanger: Stainless steel
• Venting: 2-inch PVC recommended
• Filter Size: Standard 1-inch or optional 4-inch media
• Warranty: Limited lifetime heat exchanger, 10 years parts

Controls and Settings

Access control board via front panel. LED indicator shows status codes.

Thermostat Settings: HEAT, COOL, OFF, FAN AUTO/ON. Advanced models feature programmable schedules.

Furnace Controls: Power switch, gas valve, control board with diagnostic LED, blower speed taps, limit switches. Diagnostic Codes: Flash patterns indicate specific issues (refer to troubleshooting chart). Blower Settings: Adjust speed taps for proper airflow (HEAT/COOL speeds).

Connecting Thermostat

Standard 24V thermostat connection with R, W, G, Y, C terminals.

1. Turn off power at furnace and circuit breaker.
2. Remove thermostat cover and label existing wires.
3. Connect wires: R (power), W (heat), G (fan), C (common).
4. Secure connections and replace cover.
5. Restore power and test operation.

Tip: Use compatible thermostat; consult wiring diagram for specific model.

Operating Modes

Supports heating operation with optional cooling when paired with AC.

1. Heating Mode: Thermostat calls for heat; ignitor glows; gas valve opens; burner lights.
2. Fan Operation: Blower starts after heat exchanger warms; circulates warm air.
3. Shutdown: Thermostat satisfied; gas valve closes; blower continues for cool-down.
4. Continuous Fan: Set fan to ON for constant air circulation.
5. Emergency Heat: Available on heat pump models.

WARNING! Never operate without proper filter installed. Restricted airflow can damage furnace.

Maintenance Features

Self-diagnostics: LED flash codes indicate specific issues. Filter reminder: Service light indicates when to change filter. Safety controls: Multiple limit switches and pressure sensors.

Care & Cleaning

Turn off power before servicing. Replace filters regularly (1-3 months). Keep area around furnace clear.

CAUTION! Do not attempt internal cleaning without qualified technician. Compressed air can damage components.

Regulatory Information

ANSI Z21.47: Certified for safety standards. UL listed. Meets DOE efficiency requirements. Copyright © 2025 Ruud; trademarks of Rheem Manufacturing Company. For support, visit www.ruud.com or contact 1-800-848-REEM. Professional installation required by local codes.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Furnace won't start	Power/thermostat	Check circuit breaker; verify thermostat settings; ensure door switch engaged.
No heat	Gas supply/ignition	Verify gas valve open; check for ignition flash code; inspect filter.
Short cycling	Airflow/limits	Replace dirty filter; check for blocked vents; verify proper blower operation.
Blower not working	Motor/controls	Check blower door switch; verify thermostat fan setting; inspect motor capacitor.
Unusual noises	Mechanical issues	Inspect blower wheel; check for loose panels; verify ductwork connections.

Reset: Turn power off for 30 seconds then restore. Check diagnostic LED for codes.

Service: 1-800-848-REEM; www.ruud.com