Rheem Criterion 2 Gas Furnace Manual

The Rheem Criterion 2 Gas Furnace is a high-efficiency residential heating system featuring advanced combustion technology, multiple safety controls, variable-speed blower motor, electronic ignition system, durable heat exchanger, and compatibility with standard thermostat controls. Designed for reliable performance in various climate conditions with AFUE ratings up to 96%. Below are key sections for safety, features, installation, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: Stainless steel heat exchanger, variable-speed ECM blower motor, hot surface igniter, gas valve, pressure switches, flame sensor, limit switches, and control board.

Installation Requirements

Professional installation required. Verify local codes and obtain permits.

1. Location: Install in approved area with proper clearances and combustion air.
2. Gas Connection: Use approved gas piping materials; pressure test for leaks.
3. Electrical: Connect to dedicated 120V circuit; proper grounding required.
4. Venting: Install PVC vent system according to manufacturer specifications.
5. Drainage: Connect condensate drain line to approved disposal.

WARNING! Gas appliances can be hazardous; installation must be performed by qualified technician. Ensure proper ventilation and combustion air supply.

First-Time Startup

Initial startup must be performed by qualified technician.

1. Verify all connections: Gas, electrical, venting, and drainage.
2. Check gas pressure: Adjust manifold pressure to specifications.
3. Test safety controls: Verify operation of all limit switches and sensors.
4. Check combustion: Measure flue gases for proper CO2 and oxygen levels.
5. Program thermostat: Set up heating schedule and temperature settings.

CAUTION! Never attempt to adjust gas pressure or bypass safety controls. Carbon monoxide hazard exists if improperly installed.

Technical Specifications

• Input BTU/H: 40,000 - 120,000 (varies by model)
• Output BTU/H: 38,000 - 115,000 (varies by model)
• AFUE: Up to 96%
• Gas Type: Natural gas (convertible to LP with kit)
• Electrical: 120V, 60Hz, 5-8 amps
• Static Pressure: 0.1 - 0.9 inches water column
• Venting: PVC pipe (2" or 3" diameter)
• Sound Level: < 65 dBA
• Dimensions: Varies by model (typically 21"W x 21"D x 40"H)
• Warranty: 20-year heat exchanger, 5-year parts

Controls and Operation

Integrated control board manages all furnace functions. LED status light indicates system operation and error codes.

Normal Operation Sequence: Thermostat calls for heat → inducer motor starts → pressure switch proves draft → hot surface igniter glows → gas valve opens → flame sensor confirms ignition → blower motor starts after heat exchanger warms.

Temperature Control: Use compatible thermostat to set desired temperature. Blower speed adjusts automatically for optimal comfort and efficiency.

Venting System

Uses PVC pipe for direct venting. Two-pipe system recommended for optimal efficiency.

1. Combustion Air Pipe: Brings fresh air from outside for combustion.
2. Exhaust Pipe: Vents combustion gases to outside.
3. Pipe Routing: Maintain proper slope for condensate drainage.
4. Terminations: Keep clear of windows, doors, and air intakes.

Tip: Regular inspection of vent pipes for blockages or damage is essential for safe operation.

Maintenance Procedures

Annual professional maintenance recommended. Basic homeowner maintenance includes:

1. Filter Replacement: Change air filter every 1-3 months depending on usage.
2. Visual Inspection: Check for visible damage or obstructions.
3. Area Clearance: Keep furnace area free of combustible materials.
4. Vent Inspection: Ensure vent terminals are clear of snow, leaves, or debris.
5. Professional Service: Annual cleaning and inspection by qualified technician.

WARNING! Do not attempt to service gas components, electrical connections, or heat exchanger. Always disconnect power before performing any maintenance.

Safety Features

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

Care & Cleaning

Keep furnace area clean and dry. Use soft brush or vacuum for external cleaning.

CAUTION! Never use water or cleaning chemicals on furnace components. Keep electrical components dry at all times.

Regulatory Information

UL certified for safety. ANSI Z21.47 compliant. Meets DOE efficiency standards. Manufactured to comply with U.S. safety and performance requirements. For technical support, contact Rheem at 1-800-432-8373 or visit www.rheem.com.

Troubleshooting

LED Error Codes: Consult control board LED flash pattern for specific error diagnosis.

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