Armstrong Guh Furnace Manuals

The Armstrong Guh Furnace series represents high-efficiency gas furnaces designed for residential heating applications. These furnaces feature advanced combustion technology, variable-speed blowers, and energy-efficient operation with AFUE ratings up to 98%. Below are comprehensive sections covering installation, operation, maintenance, troubleshooting, and technical specifications for the Armstrong Guh furnace models.

Features at a Glance

Key components: High-efficiency heat exchanger, variable-speed ECM blower motor, electronic ignition system, multi-speed inducer motor, and integrated control board.

Installation Guidelines

Proper installation is critical for safe and efficient operation. Follow all local codes and manufacturer specifications.

1. Location selection: Install in dry, clean area with adequate combustion air and service clearance.
2. Gas connection: Use approved gas piping materials; pressure test for leaks before operation.
3. Electrical connection: Connect to dedicated 120V circuit with proper grounding.
4. Venting: Install PVC vent pipes according to manufacturer specifications for proper draft.
5. Ductwork: Ensure proper sizing and sealing of supply and return ducts.

WARNING! Installation must be performed by qualified HVAC technician. Improper installation can cause fire, explosion, or carbon monoxide poisoning.

First-Time Setup

Initial startup and configuration procedures for new installations.

1. Gas pressure adjustment: Verify and adjust manifold gas pressure to specifications.
2. Blower speed settings: Configure blower speeds for heating mode based on duct static pressure.
3. Thermostat configuration: Connect compatible thermostat and configure heating stages.
4. Combustion analysis: Verify proper combustion with combustion analyzer.
5. Safety check: Test all safety controls including limit switches and pressure switches.

CAUTION! Never bypass safety controls. Always verify proper operation before leaving installation.

Technical Specifications

• Models: GUH Series (40,000 to 120,000 BTU/hr input)
• AFUE Rating: Up to 98% Annual Fuel Utilization Efficiency
• Gas Type: Natural Gas or LP (with conversion kit)
• Electrical: 120V, 60Hz, 1.5-5.0 Amps depending on model
• Blower Type: Variable-speed ECM motor
• Venting: PVC pipe (2" or 3" depending on model and installation)
• Operating Pressure: Natural Gas: 3.5" WC, LP: 10" WC
• Sound Rating: As low as 65 dB operating noise level
• Warranty: Limited lifetime heat exchanger, 10 years parts

Controls and Settings

Integrated furnace control board with LED status indicators and dip switch settings.

Control Board Features: Power indicator LED, status LED (flashing codes), dip switches for configuration, terminal strip for thermostat connections.

Configuration: Blower off delay, heating speed selection, accessory activation. Diagnostic: LED flash codes for troubleshooting (1 flash = normal operation, 2 flashes = pressure switch error, etc.). Temperature: High limit settings, fan control settings, thermostat response times.

Venting Requirements

Proper venting is essential for safe operation and efficiency.

1. Vent pipe material: Use only PVC, CPVC, or ABS plastic pipe approved for furnace venting.
2. Vent sizing: Follow manufacturer tables for proper pipe diameter based on furnace size and vent length.
3. Vent termination: Locate vent terminals at least 12 inches above ground level and away from windows or air intakes.
4. Slope requirements: Horizontal runs must slope upward toward termination at 1/4 inch per foot.

Tip: Always perform draft test after installation to verify proper venting.

Maintenance Procedures

Regular maintenance ensures optimal performance and longevity.

1. Monthly: Check and replace air filter as needed.
2. Annual: Professional inspection and cleaning by qualified technician.
3. Combustion system: Inspect burners, heat exchanger, and flame sensor.
4. Venting: Inspect vent pipes for obstructions or damage.
5. Electrical: Check wiring connections and control board operation.
6. Blower: Clean blower wheel and housing; lubricate if required.
7. Drain system: Clean condensate trap and drain lines.
8. Gas system: Check gas pressure and valve operation.

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

Safety Features

Multiple safety systems protect against hazardous conditions. Flame rollout switches, high limit switches, pressure switches, ignitor safety timing, blower door safety switch, and carbon monoxide detection compatibility.

Care & Maintenance

Keep furnace area clean and clear of combustible materials. Ensure adequate airflow around unit.

CAUTION! Never store flammable materials near furnace. Maintain minimum clearances specified in installation manual.

Regulatory Information

UL certified for safety standards. ANSI Z21.47 compliant for gas-fired central furnaces. Meets DOE energy efficiency standards. For technical support, contact Armstrong Air Technical Service at 1-877-874-7378 or visit www.armstrongair.com. Copyright © Armstrong Air Conditioning Inc. All rights reserved.

Troubleshooting

Reset: Turn power off for 30 seconds then restore to reset control board.

Service: 1-877-874-7378; www.armstrongair.com