Carrier Infinity 98 Furnace Installation Manual

The Carrier Infinity 98 Furnace is a high-efficiency gas furnace with modulating heating capability, variable-speed blower motor, advanced diagnostic controls, and compatibility with Carrier's Infinity System control. This furnace features up to 98.5% AFUE efficiency, quiet operation, and advanced humidity control. Below are key sections for safety, installation procedures, setup, specifications, controls, wiring, startup, and troubleshooting.

Features at a Glance

Key components: Modulating gas valve, variable-speed ECM blower motor, stainless steel heat exchanger, integrated control board, pressure switches, igniter, flame sensor.

Safety Precautions

Read all instructions before beginning installation. Follow local codes and manufacturer guidelines.

1. Disconnect electrical power before servicing.
2. Verify gas supply is turned off before connecting gas line.
3. Ensure proper ventilation and combustion air supply.
4. Use approved materials for venting and gas piping.
5. Wear appropriate personal protective equipment.

WARNING! Failure to follow safety procedures may result in fire, explosion, carbon monoxide poisoning, or electrical shock. Installation must be performed by qualified HVAC technician.

Installation Requirements

Verify site conditions meet requirements before installation.

1. Location: Indoor, protected from weather, with adequate service clearance.
2. Clearances: Minimum 24 inches front, 6 inches sides, 6 inches rear, 24 inches top.
3. Foundation: Level, solid surface capable of supporting furnace weight.
4. Venting: Category IV venting required; follow local codes for materials and routing.
5. Combustion air: Dedicated supply per local codes and manufacturer specifications.

CAUTION! Furnace is heavy; use proper lifting techniques and equipment.

Specifications

• Model Series: 59MN7
• AFUE: Up to 98.5%
• Input Capacity: 40,000 to 120,000 BTU/h (depending on model)
• Gas Type: Natural gas (LP conversion kit available)
• Electrical: 115V, 60Hz, 1.5-6.0 amps
• Blower Motor: Variable-speed ECM
• Sound Level: 68-78 dBA
• Venting: Category IV (PVC/CPVC approved)
• Dimensions: Varies by model (approx. 45" H x 21" W x 26" D)
• Weight: 150-180 lbs (depending on model)

Installation Procedures

Follow step-by-step installation sequence for proper operation.

1. Position furnace: Place on level surface with proper clearances.
2. Install filter rack: Mount appropriate filter system.
3. Connect ductwork: Seal all connections with approved mastic or tape.
4. Install venting: Category IV PVC/CPVC per local codes.
5. Connect gas line: Use approved black iron pipe with proper sizing.
6. Electrical connections: Follow wiring diagram and local codes.
7. Condensate drainage: Install trap and route to approved drain.

Tip: Verify all connections are tight and properly sealed before startup.

Venting and Combustion Air

Category IV vent system required for proper operation and safety.

1. Vent pipe: Schedule 40 PVC or CPVC, minimum 2-inch diameter.
2. Vent termination: Minimum 12 inches above grade, 3 feet from operable windows.
3. Combustion air: Dedicated piping from outside or sufficient room air per local codes.
4. Slope: Vent piping must slope back to furnace for condensate drainage.
5. Supports: Secure vent pipes every 4 feet and at changes in direction.

WARNING! Improper venting may cause carbon monoxide poisoning. Test for leaks after installation.

Electrical Wiring

Follow NEC and local electrical codes for all wiring.

1. Disconnect power: Turn off circuit breaker before wiring.
2. Line voltage: 115V connection with proper grounding.
3. Low voltage: 24V thermostat wiring; follow color coding.
4. Humidifier: Optional connections for accessory equipment.
5. Emergency heat: Dual-fuel setup with heat pump systems.

CAUTION! Verify proper voltage and polarity before energizing furnace.

Gas Piping

Use approved materials and follow local gas codes.

1. Pipe sizing: Determine based on length and BTU requirements.
2. Materials: Black iron pipe with approved thread sealant.
3. Shutoff valve: Install within 6 feet of furnace.
4. Sediment trap: Install at gas connection to furnace.
5. Pressure test: Test for leaks at maximum operating pressure.

WARNING! Use soap solution to check for gas leaks. Never use open flame.

Startup and Commissioning

Complete startup sequence for proper operation.

1. Verify installations: Check all connections and clearances.
2. Electrical power: Restore power to furnace.
3. Gas supply: Open gas shutoff valve slowly.
4. Initial ignition: Follow control board startup sequence.
5. Performance check: Verify temperature rise, gas pressure, and airflow.
6. System setup: Configure thermostat and control settings.

Tip: Document all measurements and settings for future reference.

Control System Setup

Infinity control system provides advanced features and diagnostics.

Infinity Thermostat: POWER, MODE, FAN, MENU, SYSTEM STATUS, HOLD, DONE.

Basic Setup: System type (furnace only or dual-fuel), fan control, temperature limits. Advanced Features: Dehumidification, ventilation control, scheduling, alerts. Diagnostics: Fault code display, system status, performance data. Service: Test modes, configuration settings, firmware updates.

Troubleshooting

Reset: Power cycle furnace; clear fault codes in control system.

Service: 1-800-CARRIER; www.carrier.com