janitrol furnace gmp075-3 manual

The Janitrol GMP075-3 is a 75,000 BTU gas furnace designed for residential heating applications. This natural gas furnace features a multi-speed blower motor, electronic ignition system, and safety controls including flame rollout and limit switches. Below are key sections for safety, features, installation, operation, maintenance, and troubleshooting.

1. Features at a Glance 2. Installation Requirements 3. First-Time Setup 4. Specifications 5. Controls and Settings 6. Gas Line Connection 7. Electrical Wiring 8. Venting Requirements 9. Maintenance Procedures 10. Regulatory Information 11. Troubleshooting

Features at a Glance

Key components: Gas valve, heat exchanger, multi-speed blower motor, electronic ignition, pressure switch, flame sensor, limit controls.

Feature	Description
Input Capacity	75,000 BTU/H natural gas
Blower Motor	Multi-speed, permanent split capacitor
Ignition System	Direct spark electronic ignition
Heat Exchanger	Clam shell type, aluminized steel
Gas Valve	24VAC operated, manual shutoff
Pressure Switch	Proves draft inducer operation
Flame Sensor	Proves flame during operation
Limit Switch	High temperature safety cutoff
Flame Rollout Switch	Safety switch for flame rollout conditions
Thermostat Connections	Standard 24VAC R, W, G, C terminals

Installation Requirements

Unpack and inspect furnace for shipping damage. Verify proper location with adequate clearance.

Location: Minimum 24" front clearance, 6" sides, 6" rear, 24" above for service access.
Combustion Air: Ensure adequate fresh air supply per local codes.
Gas Supply: 3/4" minimum gas line with sediment trap.
Electrical: 120VAC, 15A circuit with proper grounding.
Venting: Category I venting, minimum 3" diameter approved vent pipe.

WARNING! Installation must comply with local codes and NFPA 54. Gas line connections must be leak tested.

First-Time Setup

Complete installation verification before initial startup.

Gas Pressure Check: Verify manifold pressure at 3.5" WC for natural gas.
Venting Verification: Confirm proper draft and vent pipe slope.
Electrical Connections: Verify 120VAC power and thermostat wiring.
Initial Startup: Follow lighting instructions on furnace label.
System Check: Verify proper ignition, flame sensing, and blower operation.

CAUTION! Only qualified HVAC technicians should perform installation and startup procedures.

Specifications

Model: GMP075-3
Input BTU/H: 75,000 natural gas
Output BTU/H: 60,000
Efficiency: 80% AFUE
Blower Speeds: Multi-speed for heating/cooling
Electrical: 120VAC, 60Hz, 6.5 amps
Gas Connection: 1/2" NPT
Vent Size: 3" minimum diameter
Dimensions: 21" W x 21" D x 40" H
Shipping Weight: 98 lbs

Controls and Settings

Integrated furnace control board manages all operations. Access door switch interrupts power when door removed.

Control Board: LED status light indicates system operation and fault codes.

Thermostat Connections: R (24VAC hot), W (heat), G (fan), C (common). Blower Speeds: Adjustable for heating and cooling applications. Gas Valve: Manual shutoff, pressure regulator, 24VAC operator. Limit Controls: Auto-reset high limit switch, manual reset flame rollout switch.

Gas Line Connection

Gas supply connection requirements and procedures.

Shut off main gas supply before connecting.
Install sediment trap/drip leg before gas valve.
Use approved pipe thread compound or tape.
Pressure test all connections for leaks.
Verify manifold pressure: 3.5" WC natural gas.

Tip: Always use gas leak detection solution, never flame, to check for leaks.

Electrical Wiring

120VAC power supply and low voltage thermostat connections.

Disconnect power before servicing.
Connect 120VAC line voltage to designated terminals.
Connect thermostat wires: R, W, G, C as required.
Verify proper grounding of furnace chassis.
Check polarity of 120VAC connections.

WARNING! Electrical work must comply with NEC and local codes. Use proper wire sizing and overcurrent protection.

Venting Requirements

Category I vent system requirements for proper combustion and venting.

Use approved vent pipe materials (Type B or L).
Maintain minimum 1/4" per foot upward slope.
Provide adequate clearance to combustibles.
Install vent cap with proper clearance above grade.
Verify proper draft with manometer.

CAUTION! Improper venting can cause carbon monoxide hazards. Test for spillage at draft hood.

Maintenance Procedures

Annual maintenance recommended for optimal performance and safety.

Filter Replacement: Replace air filter monthly during heating season.
Blower Cleaning: Vacuum blower wheel and housing annually.
Heat Exchanger: Inspect for cracks or corrosion.
Flame Sensor: Clean with emery cloth annually.
Burner Cleaning: Remove and clean burners as needed.
Vent System: Inspect for obstructions or deterioration.

WARNING! Disconnect power and gas supply before performing maintenance.

Regulatory Information

ANSI Z21.47: Certified for natural gas operation. UL listed. Installation must comply with NFPA 54 (National Fuel Gas Code) and local building codes. For technical support, contact Janitrol at 1-800-727-3507 or visit www.janitrol.com.

Troubleshooting

Symptom	Possible Cause	Corrective Action
No heat	Thermostat, power, gas supply	Check thermostat setting, circuit breaker, gas valve position.
Blower not running	Door switch, motor, capacitor	Ensure door closed properly; check blower motor and capacitor.
Furnace locks out	Flame sensor, pressure switch	Clean flame sensor; check pressure switch tubing.
Ignition failure	Gas valve, igniter, control board	Verify gas supply; check igniter for cracks; test control board.
Limit switch trips	Airflow restriction	Check filter; verify blower operation; ensure registers open.

LED Codes: Blink patterns indicate specific fault conditions (refer to control board label).

Service: 1-800-727-3507; www.janitrol.com