Goodman Furnace Installation Manual GMEC96

The Goodman GMEC96 is a high-efficiency gas furnace with 96% AFUE rating, multi-speed ECM blower motor, two-stage gas valve operation, durable aluminized steel heat exchanger, diagnostic LED lights, easy-access control board, and compatibility with various thermostat systems. Designed for residential forced-air heating applications with proper venting requirements. Below are key sections for safety, installation procedures, electrical connections, startup, and troubleshooting.

Features at a Glance

Key components: Two-stage gas valve, ECM blower motor, aluminized steel heat exchanger, diagnostic control board, pressure switches, flame sensor, hot surface ignitor.

Pre-Installation Requirements

Verify local codes and obtain necessary permits before installation.

1. Location selection: Install in dry, clean area with adequate combustion air and service clearance.
2. Combustion air: Ensure proper fresh air supply per local codes.
3. Clearances: Maintain minimum 1-inch clearance from combustible materials.
4. Gas supply: Verify adequate gas pressure and pipe sizing.
5. Electrical: Dedicated 120V circuit required.

WARNING! Installation must comply with all local codes and ordinances. Gas furnaces can produce carbon monoxide - proper venting is critical.

Installation Procedures

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

1. Position furnace: Level unit on solid base or platform.
2. Duct connections: Connect supply and return ducts securely.
3. Gas line: Connect gas supply with approved pipe compound.
4. Venting: Install PVC vent pipes per manufacturer specifications.
5. Electrical: Connect line voltage and thermostat wiring.
6. Condensate: Route condensate drain to proper disposal.

CAUTION! Use two people for lifting; furnace is heavy. Test for gas leaks with soap solution.

Specifications

• Model: GMEC96 Series
• AFUE: 96%
• Input BTU: 40,000 - 120,000 (varies by model)
• Stages: Two-stage heating operation
• Blower: ECM variable speed
• Electrical: 120V, 60Hz
• Gas Type: Natural gas (LP conversion kit available)
• Venting: 2" PVC pipe minimum
• Warranty: Limited lifetime heat exchanger, 10-year parts

Electrical Connections

Connect to dedicated 120V circuit with proper grounding.

Thermostat: Connect R, W, G, C, Y1/Y2 terminals per wiring diagram.

Line voltage: Black to hot, white to neutral, green to ground. Low voltage: Follow color-coded thermostat connections. Install 3-5 amp fuse in furnace disconnect. Verify proper polarity and grounding.

Gas Line Connections

Use approved gas pipe and fittings. Test for leaks.

1. Turn off gas supply at main valve.
2. Connect gas line with proper pipe size (typically 1/2" to 3/4").
3. Use pipe dope approved for natural/LP gas on male threads only.
4. Install sediment trap before gas valve.
5. Test all connections with soap solution - no bubbles should form.

Tip: Always use two wrenches when connecting gas lines to prevent damage.

Venting System

PVC vent pipe required for high-efficiency operation.

1. Route vent pipes: Follow manufacturer guidelines for maximum length and elbows.
2. Termination: Locate vent termination away from windows, doors, and air intakes.
3. Slope: Pitch condensate drain line 1/4" per foot toward drain.
4. Sealing: Use PVC primer and cement for all joints.
5. Support: Secure pipes every 4 feet with proper hangers.

WARNING! Improper venting can cause carbon monoxide poisoning. Never use metal vent pipe.

Startup and Commissioning

Complete system checkout before initial operation.

1. Gas pressure: Verify manifold pressure (3.5" WC natural gas).
2. Electrical: Check voltage at control board and thermostat.
3. Venting: Confirm proper draft and pressure switch operation.
4. Combustion: Measure flue gas temperature and CO levels.
5. Airflow: Verify proper CFM and temperature rise.
6. Sequence: Observe complete heating cycle from thermostat call to shutdown.

CAUTION! Only qualified technicians should perform combustion analysis.

Maintenance Guidelines

Regular maintenance ensures optimal performance and safety.

Monthly: Check and replace air filter as needed. Annually: Professional inspection including heat exchanger examination, burner cleaning, flame sensor cleaning, blower maintenance, and safety control testing.

CAUTION! Turn off power and gas before performing any maintenance. Only qualified technicians should service gas components.

Regulatory Information

UL certified for safety standards. ANSI Z21.47 compliant for gas furnace operation. Installation must comply with National Fuel Gas Code NFPA 54/ANSI Z223.1 and National Electrical Code NFPA 70. For technical support, contact Goodman Manufacturing at 1-877-466-8626 or visit www.goodmanmfg.com.

Troubleshooting

Reset: Power cycle furnace at disconnect or circuit breaker.

Service: 1-877-466-8626; www.goodmanmfg.com