Nordyne MGHA-077A AA FC-02 User Manual

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Nordyne MGHA-077A AA FC-02 Specifications

General

Model	MGHA-077A AA FC-02
Heating Capacity	77, 000 BTU
Efficiency Rating	80% AFUE
Fuel Type	Natural Gas
Weight	120 lbs
Efficiency	80%
Gas Type	Natural Gas
Vent Size	4 inch

Summary

LIMITED WARRANTY

MANUFACTURER WARRANTY, OWNER'S RESPONSIBILITIES

INSTALL FURNACE AND ROOF JACK

INSTALL FURNACE

Instructions for placing and securing the furnace onto the duct connector.

INSTALL ROOF JACK

Steps for applying caulking and securing the roof jack assembly.

ELECTRICAL WIRING

Power Supply Circuit Requirements

CONNECT POWER SUPPLY WIRES

CONNECT THERMOSTAT WIRES

FUEL PIPING

General Fuel Piping Requirements

GAS PIPING

OIL PIPING

LIGHTING AND FURNACE SHUT DOWN

SAFETY INFORMATION

Critical safety warnings and procedures, especially regarding gas leaks.

LIGHTING INSTRUCTIONS FOR STANDING PILOT MODELS

Step-by-step guide for lighting the pilot on standing pilot models.

TO TURN OFF GAS TO APPLIANCE

Steps to safely turn off the gas supply to the appliance.

SEQUENCE OF OPERATION

STANDING PILOT MODELS

STANDING PILOT W/ INDUCED DRAFT BLOWERS

GENERAL-DIRECT IGNITION MODELS

OPERATING INSTRUCTIONS FOR MM-MODELS WITH DIRECT IGNITION

OPERATING INSTRUCTIONS FOR OIL AND GAS GUN FURNACE

SERVICE GUIDE

TROUBLESHOOTING - STANDING PILOT MODELS

Main Burner Does Not Come On

Steps to diagnose why the main burner is not igniting.

Pilot Will Not Light or Goes Out

Troubleshooting steps for pilot light issues.

TROUBLESHOOTING - DIRECT IGNITION FURNACES INCLUDING GAS GUN

Burner Motor Does Not Run

Diagnosing issues when the burner motor fails to operate.

Combustion Blower Issues

Combustion Blower Does Run - No Flame

Troubleshooting steps when the blower runs but there is no flame.

Control Module Issues

Diagnosing ignitor and control module operational problems.

Main Flame Ignites - Burner Locks Out

Troubleshooting when the main flame ignites but the burner locks out.

Burner Short Cycling

Identifying causes for the burner cycling on and off too frequently.

Burner Operates - Insufficient Heat

Diagnosing reasons for insufficient heat output from the furnace.

MAINTENANCE

WIRING DIAGRAMS

REPLACEMENT PARTS LIST