Ruud 80 Plus Furnace Manual

The Ruud 80 Plus Furnace is a high-efficiency gas furnace with AFUE ratings up to 80%, featuring electronic ignition, multi-speed blower motor, durable heat exchanger, safety controls, and compatibility with standard thermostat systems. Designed for residential heating applications with natural gas or propane capability. Below are key sections for safety, features, installation, operation, maintenance, and troubleshooting.

1. Features at a Glance 2. Installation Requirements 3. Initial Setup & Startup 4. Technical Specifications 5. Controls and Operation 6. Venting and Combustion Air 7. Maintenance Procedures 8. Safety Features 9. Care & Cleaning 10. Regulatory Information 11. Troubleshooting

Features at a Glance

Key components: Heat exchanger, blower assembly, gas valve, ignition system, pressure switches, limit controls, filter rack.

Feature	Description
Heat Exchanger	Durable aluminized steel construction
Blower Motor	Multi-speed ECM or PSC motor
Ignition System	Hot surface or intermittent pilot
Gas Valve	Automatic gas flow regulation
Pressure Switches	Verify proper venting operation
Limit Controls	Prevent overheating conditions
Filter Rack	Standard 1-inch or 4-inch media filter
Control Board	Integrated furnace controller
Drain System	Condensate removal for high-efficiency models
Thermostat Connection	Standard 24VAC control wiring

Installation Requirements

Professional installation required. Verify local codes and obtain permits.

Location: Install in approved spaces with proper clearances.
Venting: Use approved PVC or metal venting materials.
Gas Supply: Proper gas line sizing and connection.
Electrical: 120VAC power supply with proper grounding.
Drainage: Condensate drain line installation.

WARNING! Gas appliances can be hazardous; installation must comply with all codes. Use qualified HVAC technician.

Initial Setup & Startup

Professional startup procedure required.

Verify installation: Check all connections and clearances.
Gas pressure: Set manifold pressure to specifications.
Electrical: Verify proper voltage and polarity.
Venting: Confirm proper draft and combustion air.
Test operation: Cycle furnace through heating mode.
Safety checks: Verify limit controls and pressure switches.

CAUTION! Never bypass safety controls. Carbon monoxide hazard possible with improper installation.

Technical Specifications

AFUE Rating: Up to 80%
Input BTU/H: 40,000 - 120,000 (varies by model)
Gas Type: Natural gas or propane
Electrical: 120VAC, 60Hz
Blower Speeds: Multi-speed for heating/cooling
Venting: Category I or IV (model dependent)
Sound Rating: Standard residential operation
Warranty: Limited lifetime heat exchanger
Operating Temp: Standard indoor conditions

Controls and Operation

Thermostat controls furnace operation. Integrated control board manages safety sequences.

Operation Sequence: Thermostat call for heat > inducer motor start > pressure switch verification > ignition sequence > gas valve opening > flame verification > blower activation.

User Controls: Thermostat temperature setting, system switch (heat/off/cool), fan switch (auto/on). Service Controls: Diagnostic LED, pressure tap ports, gas valve adjustment.

Venting and Combustion Air

Proper venting critical for safe operation.

Vent Materials: Use only approved PVC, CPVC, or metal.
Vent Routing: Maintain proper slope and support.
Termination: Follow clearance requirements for vent terminals.
Combustion Air: Ensure adequate fresh air supply.
Inspection: Regular visual inspection of vent system.

Tip: Keep vent terminals clear of snow, debris, and obstructions.

Maintenance Procedures

Regular maintenance ensures efficiency and safety.

Filter Replacement: Monthly inspection, replace as needed.
Blower Cleaning: Annual cleaning of blower assembly.
Heat Exchanger: Visual inspection for cracks or damage.
Vent System: Check for obstructions or deterioration.
Burner Cleaning: Remove debris from burners.
Drain System: Flush condensate lines annually.

WARNING! Turn off power and gas supply before servicing. Use qualified technician for complex maintenance.

Safety Features

Multiple safety systems protect against hazardous conditions.

Safety Device	Function
Flame Rollout Switch	Detects improper burner flames
High Limit Switch	Prevents overheating
Pressure Switches	Verify venting operation
Flame Sensor	Confirms burner ignition
Gas Valve	Automatic gas shutoff
Ignition Control	Safe ignition sequencing

Care & Cleaning

Regular cleaning maintains performance and efficiency.

Exterior: Wipe with damp cloth. Interior: Professional cleaning recommended. Filter: Replace regularly. Burners: Clean annually. Drain System: Flush with clean water.

CAUTION! Never use chemical cleaners inside furnace. Keep area around furnace clean and dry.

Regulatory Information

UL listed. ANSI Z21.47 compliant. CSA certified. Meets U.S. Department of Energy efficiency standards. Installation must comply with National Fuel Gas Code (NFPA 54), National Electrical Code (NFPA 70), and local codes. For support, contact Ruud Customer Service at 1-800-848-4070 or visit www.ruud.com.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Furnace won't start	Power, thermostat, safety lockout	Check power supply; verify thermostat setting; reset power.
No heat	Gas supply, ignition, filter	Verify gas valve on; check filter; inspect ignition system.
Short cycling	Filter, limit switch, airflow	Replace filter; check airflow; verify limit switch operation.
Blower won't stop	Thermostat, control board	Check thermostat fan setting; inspect control board.
Unusual noises	Blower, inducer, ductwork	Inspect blower wheel; check inducer motor; examine ducts.
Error codes	Safety lockout, sensor failure	Refer to diagnostic chart; reset if safe; call technician.

Reset: Turn power off for 30 seconds, then restore.

Service: 1-800-848-4070; www.ruud.com