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GMC GUN125-4B gas furnace

GMC GUN125-4B gas furnace Parts

Here are the diagrams and repair parts for GMC GUN125-4B gas furnace, as well as links to manuals and error code tables, if available.

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Browse Parts for GUN125-4B Gas Furnace

Blower assembly diagram
Capacitor 15
Part #B9456-53
Replaced by #12910
Manufacturer substitution
This part replaces B9456-53. Substitute parts can look different from the original.
In Stock
$7.95
11% OFF Phone Price : $8.95
Qty
Blower assembly diagram
Capacitor 10
Part #B9456-52
Replaced by #12908
Manufacturer substitution
This part replaces B9456-52. Substitute parts can look different from the original.
In Stock
$98.90
11% OFF Phone Price : $110.90
Qty
Gas train diagram
Hot Surface
Part #B14010-09
Replaced by #IG412
Manufacturer substitution
This part replaces B14010-09. Substitute parts can look different from the original.
In Stock
$29.09
Qty
Blower assembly diagram
Blower Shell
Part #18393-00
Replaced by #0271A00016S
Manufacturer substitution
This part replaces 18393-00. Substitute parts can look different from the original.
In Stock
$136.57
8% OFF Phone Price : $148.57
Qty
Heat exchanger assembly diagram
Heat Exchange
Part #18212-30S
The manufacturer no longer makes this part, and there's no substitute part
Casing diagram
Casing Assembly
Part #18161-31S
The manufacturer no longer makes this part, and there's no substitute part
Gas train diagram
Burner Assembly
Part #B18225-08
The manufacturer no longer makes this part, and there's no substitute part
Heat exchanger assembly diagram
Transfer Tub
Part #B18102-02
The manufacturer no longer makes this part, and there's no substitute part
Gas train diagram
Manifold, 4
Part #B18264-14
The manufacturer no longer makes this part, and there's no substitute part
Casing diagram
Top Channel (gun100-4b, Gus100-4)
Part #18221-05S
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.

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 vibrate a lot?

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

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 cut unevenly?

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

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 run rough?

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

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.

How to replace a lawn mower front deck tray

How to replace a lawn mower front deck tray

Learn how to replace the front deck tray on your lawn mower if it's cracked or damaged.…

Repair time and Difficulty

60 minutes or less

How to replace a lawn mower transmission

How to replace a lawn mower transmission

Learn how to replace the transmission on your lawn mower if it's locked up or won't drive the wheels.…

Repair time and Difficulty

60 minutes or less

How to replace a lawn mower flywheel key on a flathead engine

How to replace a lawn mower flywheel key on a flathead engine

When you hit a hard object with your mower, the flywheel can shear to protect more expensive components. Learn how to re…

Repair time and Difficulty

45 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.

How to get your furnace ready for winter

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.…

2023 HVAC regulation changes and how they may affect you

2023 HVAC regulation changes and how they may affect you

Find out how new DOE standards going into effect in 2023 can affect you and what you need to do.…

Top questions about Sears and Sears PartsDirect

Top questions about Sears and Sears PartsDirect

Get answers to frequently asked questions about Sears and Sears PartsDirect.…