Goodman Furnace Manual GMP100-3

The Goodman GMP100-3 is a high-efficiency gas furnace designed for residential heating applications. This model features a multi-speed blower motor, electronic ignition system, durable heat exchanger, and safety controls including flame rollout and limit switches. With AFUE ratings up to 95%, it provides reliable and efficient heating performance. Below are key sections for safety, features, installation, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: Multi-speed direct drive blower, hot surface igniter, aluminized steel tubular heat exchanger, induced draft blower, integrated control board.

Installation Requirements

Professional installation required. Verify local codes and obtain permits.

1. Location: Install in level, clean area with adequate service clearance.
2. Venting: Use approved PVC pipe for combustion air and flue gas.
3. Gas Supply: Connect to proper gas line with sediment trap.
4. Electrical: Connect to 120V AC power with proper grounding.
5. Ductwork: Ensure proper sizing and sealing of supply/return ducts.

WARNING! Gas furnaces produce carbon monoxide. Proper venting is critical for safety. Installation must comply with all local codes.

First-Time Setup

Initial startup must be performed by qualified technician.

1. Verify all connections: Gas, electrical, venting, and condensate drain.
2. Check gas pressure: Adjust manifold pressure per specifications.
3. Test safety controls: Verify operation of all limit switches and sensors.
4. Start furnace: Follow proper lighting procedure and check flame.
5. Adjust blower speed: Set appropriate CFM for heating application.

CAUTION! Never bypass safety controls. Carbon monoxide poisoning can occur with improper installation or operation.

Technical Specifications

• Model: GMP100-3
• Input BTU/H: 100,000
• Output BTU/H: Up to 95,000
• AFUE Rating: Up to 95%
• Gas Type: Natural Gas
• Manifold Pressure: 3.5" W.C.
• Electrical: 120V AC, 60Hz
• Motor Type: Multi-speed direct drive
• Venting: PVC, CPVC, or ABS
• Dimensions: Refer to installation manual
• Weight: Approximately 125 lbs

Controls and Operation

Thermostat controls furnace operation. Integrated control board manages sequence of operation.

Operation Sequence: Thermostat calls for heat → Inducer motor starts → Pressure switch proves draft → Hot surface igniter heats → Gas valve opens → Flame sensor confirms ignition → Blower motor starts after heat exchanger warms.

Thermostat Settings: HEAT/COOL/OFF selector, temperature setpoint, fan AUTO/ON control.

Control Board LED: Flashing pattern indicates operational status and fault codes.

Venting and Combustion Air

Two-pipe direct vent system recommended for optimal performance and safety.

1. Combustion Air Pipe: Brings outside air to furnace for combustion.
2. Flue Gas Pipe: Exhausts combustion products outdoors.
3. Pipe Sizing: Follow manufacturer specifications for pipe diameter and length.
4. Termination: Maintain proper clearances from windows, doors, and air intakes.

Tip: Ensure vent pipes are properly sloped to drain condensate back to furnace.

Maintenance Procedures

Annual professional maintenance recommended. Some tasks can be performed by homeowner.

1. Air Filter: Replace every 1-3 months depending on usage and environment.
2. Blower Assembly: Clean annually, check for proper operation.
3. Heat Exchanger: Professional inspection for cracks or corrosion.
4. Burners: Clean and verify proper flame pattern.
5. Vent System: Inspect for obstructions or damage.
6. Drain System: Clean condensate trap and drain lines.
7. Safety Controls: Test operation of all limit switches and sensors.

WARNING! Turn off electrical power and gas supply before performing any maintenance.

Safety Features

Flame Rollout Switch: Shuts off gas if flame rolls out of burner compartment. High Limit Switch: Prevents overheating. Pressure Switch: Ensures proper venting before ignition. Flame Sensor: Confirms burner ignition. Ignition Control: Limits ignition attempts.

Care & Cleaning

Keep furnace area clean and free of combustible materials. Use soft brush or vacuum for cleaning.

CAUTION! Never use water or liquid cleaners on electrical components. Keep filter clean for proper airflow and efficiency.

Regulatory Information

UL listed and ANSI certified. Complies with U.S. Department of Energy efficiency standards. Manufactured to meet or exceed industry standards for safety and performance. For technical support, contact Goodman Manufacturing at 1-877-466-8626 or visit www.goodmanmfg.com.

Troubleshooting

Reset: Turn power off for 30 seconds then restore. Check control board LED for fault codes.

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