Model # GMN120-5 Official GMC gas furnace

Here are the diagrams and repair parts for Official GMC GMN120-5 gas furnace, as well as links to manuals and error code tables, if available.

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Model diagram and schematic

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Showing 10 of 66 parts |

#34

Heat exchangers/misc.electrical diagram

Transformer

Part #B11416-00

The manufacturer no longer makes this part, and there's no substitute part

#40

Heat exchangers/misc.electrical diagram

Hsi module

Part #B18099-08

Replaced by #B1809913S

This item is not returnable

$185.31 |

6% OFF Phone Price : $197.31

In Stock

Qty

Heat exchangers/misc.electrical diagram

Hot surface

Part #B14010-09S

Replaced by #41-412

$49.15 |

11% OFF Phone Price : $55.15

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Qty

#38

Heat exchangers/misc.electrical diagram

Capacitor 15

Part #B9456-53

Replaced by #12910

$8.37 |

11% OFF Phone Price : $9.37

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Qty

Heat exchangers/misc.electrical diagram

Flame sensor

Part #B11726-06

$16.00 |

11% OFF Phone Price : $18.00

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Heat exchangers/misc.electrical diagram

Gas valve

Part #B12826-15

The manufacturer no longer makes this part, and there's no substitute part

#11

Heat exchangers/misc.electrical diagram

Limit

Part #B13700-10

Replaced by #1370910S

$55.18 |

10% OFF Phone Price : $61.18

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Qty

#22

Heat exchangers/misc.electrical diagram

Heat exchange

Part #B28646-03

Replaced by #2864607S

$771.18

In Stock

Qty

Heat exchangers/misc.electrical diagram

Burner side

Part #25140-00

Replaced by #0121F00146

This item is not returnable

$6.57

Back Order

Qty

#17

Heat exchanger diagram

Motor mounting bracket

Part #B13768-59

The manufacturer no longer makes this part, and there's no substitute part

Symptoms for gas walk-behind mowers

Choose a symptom to see related walk-behind mower repairs.

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Why won't my lawn mower move?

Main causes: drive control cable failure, worn or broken drive belt, bad transmission, broken drive wheel…

Why does my lawn mower run rough?

Main causes: engine needs tune up, dirty or clogged carburetor, damaged flywheel key…

Why does my lawn mower stall?

Main causes: dirty carburetor, bad spark plug, clogged air filter, engine choke problems, clogged gas cap vent…

Why does my lawn mower vibrate a lot?

Main causes: damaged cutting blade, loose cutting blade, damaged flywheel key, engine needs tune up…

Why won't my lawn mower start?

Main causes: stale gas, engine needs tune up, bad spark plug, dead battery, bad recoil starter, faulty safety switch, ba…

Why does my lawn mower cut unevenly?

Main causes: uneven wheel height settings, damaged wheel, dull or damaged cutting blade…

Repair guides for gas walk-behind mowers

These step-by-step repair guides will help you safely fix what’s broken on your walk-behind lawn mower.

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How to replace a lawn mower spark plug

Take a few minutes to replace the spark plug during your lawn mower's annual tune-up or if the spark plug is burnt or cr…

Repair difficulty

Time required

15 minutes or less

How to replace a lawn mower drive cable

The drive cable engages the transmission to spin the drive wheels and move the mower across the grass. Replace the drive…

Repair difficulty

Time required

60 minutes or less

How to replace a lawn mower starter rope

These step-by-step instructions show how to replace a broken starter pull rope on a walk-behind lawn mower.…

Repair difficulty

Time required

30 minutes or less

Effective articles & videos to help repair your furnaces

Use the advice and tips in these articles and videos to get the most out of your walk-behind lawn mower.

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How to get your furnace ready for winter

Get expert tips for preparing your furnace for winter. Follow maintenance tips to keep your furnace in top shape.…

Introducing new technical repair content that we’re developing for the Sears Technical Institute

Learn about Sears Technical Institute and the advanced technical content being developed for aspiring appliance techs.…

Top questions about Sears and Sears PartsDirect

Model # GMN120-5 Official GMC gas furnace

Model diagram and schematic

SEARCH WITHIN THIS MODEL

Symptoms for gas walk-behind mowers

Why won't my lawn mower move?

Why does my lawn mower run rough?

Why does my lawn mower stall?

Why does my lawn mower vibrate a lot?

Why won't my lawn mower start?

Why does my lawn mower cut unevenly?

Repair guides for gas walk-behind mowers

How to replace a lawn mower spark plug

How to replace a lawn mower drive cable

How to replace a lawn mower starter rope

Effective articles & videos to help repair your furnaces

How to get your furnace ready for winter

Introducing new technical repair content that we’re developing for the Sears Technical Institute

Top questions about Sears and Sears PartsDirect

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