Intertherm Gas Furnace Owners Manual

The Intertherm Gas Furnace is a high-efficiency heating system designed for residential use, featuring natural gas operation, electronic ignition, variable-speed blower motor, multi-speed settings, safety shut-off controls, diagnostic LED indicators, and energy-saving operation modes. Below are key sections for safety, features, installation, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: Gas valve assembly, heat exchanger, blower motor, electronic ignition system, thermostat connection, pressure switches, flame sensor, and diagnostic LED.

Installation Requirements

Unpack and inspect all components. Ensure proper clearances and venting.

1. Location requirements: Minimum 1-inch clearance from combustible materials; level installation surface.
2. Gas connection: Use approved gas piping; pressure test for leaks before operation.
3. Electrical connection: 120V AC power supply; proper grounding required.
4. Venting system: Category I venting; proper slope and termination.
5. Thermostat wiring: Connect R, W, G, C terminals as required.

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

First-Time Setup

Complete installation verification before initial startup.

1. Gas pressure adjustment: Set manifold pressure to 3.5" WC for natural gas.
2. Blower speed settings: Adjust dip switches for proper airflow.
3. Thermostat configuration: Set to heat mode; verify temperature differential.
4. System check: Run complete heating cycle; verify all safety controls.
5. Combustion analysis: Verify proper CO levels and efficiency.

CAUTION! Never bypass safety controls. Test carbon monoxide detectors after installation.

Technical Specifications

• Heating Capacity: 40,000 - 120,000 BTU/h (model dependent)
• Fuel Type: Natural Gas
• Efficiency: 80% AFUE minimum
• Electrical: 120V AC, 60Hz, 5-15 Amp circuit
• Gas Connection: 1/2" NPT
• Vent Size: 3" - 5" diameter (model dependent)
• Blower Motor: ECM variable speed
• Filter Size: 16x25x1 inch standard
• Operating Temp Range: -30°F to 120°F ambient
• Warranty: 20-year heat exchanger, 5-year parts

Controls and Settings

Access control board via front panel. Integrated control module with diagnostic capabilities.

Control Board: POWER switch, STATUS LED, DIP switches, fuse, reset button.

Thermostat Settings: HEAT/COOL/OFF mode, FAN AUTO/ON, temperature setpoint. Blower Settings: Multi-speed configurations via DIP switches. Gas Valve: Pressure adjustment screw, manual shutoff. Safety Controls: Limit switches, rollout switches, pressure switches, flame sensor.

Operating Instructions

Normal heating cycle operation and seasonal startup procedures.

1. Seasonal startup: Turn power on; set thermostat to desired temperature.
2. Heating cycle: Ignition sequence begins; blower starts after heat exchanger warms.
3. Continuous operation: Maintains set temperature via thermostat cycling.
4. Shutdown: Set thermostat to OFF or lower temperature below room temp.
5. Summer operation: Turn power off or set to COOL if AC equipped.

Tip: Allow 30 seconds between thermostat adjustments to prevent short cycling.

Maintenance Procedures

Regular maintenance ensures optimal performance and safety.

1. Monthly: Check and replace air filter if dirty.
2. Seasonal: Inspect vent system for obstructions; check burners for cleanliness.
3. Annual: Professional inspection of heat exchanger, gas pressure, safety controls.
4. Blower maintenance: Clean blower wheel and housing annually.
5. Drain system: Clear condensate drain line on high-efficiency models.

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

Safety Features

Multiple safety systems protect against hazardous conditions.

Care & Cleaning

Proper cleaning maintains efficiency and extends furnace life.

1. Air filter: Replace every 1-3 months during heating season.
2. Burners: Professional cleaning only - do not attempt yourself.
3. Blower assembly: Vacuum accessible areas annually.
4. Vent system: Inspect for bird nests or debris blockage.
5. Exterior: Wipe with dry cloth only; no liquids or cleaners.

CAUTION! Never use water or chemical cleaners on furnace components. Keep area around furnace clear of flammable materials.

Regulatory Information

ANSI Z21.47/CSA 2.3: Certified for natural gas operation. UL listed for electrical safety. Meets DOE efficiency standards. Manufactured to comply with U.S. safety and performance requirements. For technical support, contact Intertherm customer service at 1-800-XXX-XXXX or visit www.intertherm.com. Keep this manual for future reference.

Troubleshooting

Reset Procedure: Turn power off for 30 seconds, then restore.

Service: 1-800-XXX-XXXX; www.intertherm.com