Rheem Criterion II Gas Furnace Owners Manual

The Rheem Criterion II Gas Furnace is a high-efficiency residential heating system featuring multi-speed blower operation, electronic ignition, sealed combustion, and durable heat exchanger construction. Designed for natural gas operation with optional LP gas conversion capability. Below are key sections for safety, features, installation, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: Durable aluminized steel heat exchanger, multi-speed direct drive blower, hot surface ignition system, sealed combustion chamber, integrated control board.

Installation Requirements

Professional installation required. Verify local codes and obtain permits.

1. Location: Install in approved locations with proper clearances to combustibles.
2. Venting: Use approved PVC or CPVC vent pipe per manufacturer specifications.
3. Gas Supply: Connect to properly sized gas line with sediment trap.
4. Electrical: Connect to 120V AC power with proper grounding.
5. Ductwork: Ensure proper return and supply air duct sizing.

WARNING! Gas furnaces produce carbon monoxide; proper installation and venting are critical for safety. Installation must comply with NFPA 54 and local codes.

First-Time Operation

After professional installation, follow these steps for initial startup.

1. Verify all access panels are properly installed and secured.
2. Ensure gas supply valve is open and electrical power is connected.
3. Set thermostat to lowest setting, then to heat mode above room temperature.
4. Listen for ignition sequence and verify proper burner operation.
5. Check for proper airflow and temperature rise within specified range.

CAUTION! If you smell gas, immediately turn off gas supply, evacuate area, and call gas company from safe location.

Technical Specifications

• Input Capacity: 40,000 to 120,000 BTU/H (model dependent)
• Efficiency: 80% AFUE standard
• Gas Type: Natural gas (LP conversion kit available)
• Electrical: 120V AC, 60Hz, 1.5-5.0 amps
• Blower Speeds: Multi-speed for heating and continuous fan operation
• Venting: PVC/CPVC sidewall or vertical venting
• Filter Size: Standard 1-inch throwaway filters
• Warranty: 20-year heat exchanger limited warranty
• Operating Temp Rise: 35-65°F (model specific)

Controls and Settings

Integrated control board manages all furnace operations with LED status indicator.

Thermostat: HEAT/COOL/OFF selector, FAN AUTO/ON, temperature setting.

Control Board: Monitors safety devices, controls ignition sequence, blower operation, and provides diagnostic codes via LED flash patterns. Blower Speed: Factory set for optimal airflow; adjustable for specific installation requirements by qualified technician. Limit Controls: Automatic high temperature shutdown with manual reset. Pressure Switch: Ensures proper venting before allowing ignition.

Venting and Combustion Air

Sealed combustion system uses separate intake and exhaust vents.

1. Vent pipes must be properly sloped to drain condensation.
2. Maintain minimum clearances from windows, doors, and air intakes.
3. Use only approved PVC or CPVC vent materials.
4. Ensure combustion air intake is free from obstructions.

Tip: Regularly inspect vent terminals for blockages from snow, leaves, or debris.

Maintenance Procedures

Regular maintenance ensures optimal performance and safety.

1. Monthly: Check and replace air filter if dirty.
2. Seasonal: Inspect vent system for obstructions or damage.
3. Annual: Professional inspection and cleaning recommended.
4. Blower compartment: Clean annually when accessible.
5. Burners: Professional cleaning only - do not attempt yourself.
6. Drain system: Check condensate drain line for proper flow.

WARNING! Only qualified technicians should service gas train components. Improper service can create hazardous conditions.

Safety Features

Multiple safety systems protect against hazardous conditions: Flame rollout switches, high limit controls, pressure switches, flame sensor, and ignition control safety timing.

Care & Cleaning

Keep furnace area clean and free from combustible materials. Clean exterior with damp cloth only.

CAUTION! Never use flammable cleaners or sprays near furnace. Keep filter clean for proper airflow and efficiency.

Regulatory Information

ANSI Z21.47: Certified for natural and manufactured gases. CSA International certified. UL listed. Manufactured to comply with U.S. Department of Energy efficiency standards. For technical support, contact Rheem at 1-800-432-8373 or visit www.rheem.com.

Troubleshooting

Reset: Turn power off for 30 seconds, then restore. If problem persists, call for service.

Service: 1-800-432-8373; www.rheem.com