Goodman
Furnace

Model # GMNT120-5B Official Goodman gas furnace

Here are the diagrams and repair parts for Official Goodman GMNT120-5B gas furnace, as well as links to manuals and error code tables, if available.

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Showing 10 of 154 parts  |

Furnace Hot-surface Ignition Control Board (replaces 18099-13s, B18099-13s) B1809913S
#291

Misc. components/drain kit assembly diagram

Furnace hot-surface ignition control board (replaces 18099-13s, b18099-13s)

Part #B1809913S

This item is not returnable
$185.31
6% OFF Phone Price : $197.31
In Stock
Wheel B1368047A
#241

Blower assembly diagram

Wheel

Part #B1368047A

Replaced by #D6723306S

?
Manufacturer substitution
This part replaces B1368047A. Substitute parts can look different from the original.
$119.58
9% OFF Phone Price : $131.58
In Stock
Flame Sensor B1172606
#141

Burner box assembly diagram

Flame sensor

Part #B1172606

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

Furnace Auxiliary Limit Control (replaces B13701-11) B13701-55
#401

Blower assembly diagram

Furnace auxiliary limit control (replaces b13701-11)

Part #B13701-55

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

Furnace Temperature Limit Switch B1370198
#91

Heat exchanger assembly diagram

Furnace temperature limit switch

Part #B1370198

In Stock
Furnace Secondary Heat Exchanger 4021309S
#61C

Heat exchanger assembly diagram

Furnace secondary heat exchanger

Part #4021309S

$192.79
6% OFF Phone Price : $204.79
In Stock
Furnace Burner B4022700
#181

Burner box assembly diagram

Furnace burner

Part #B4022700

$21.16
22% OFF Phone Price : $27.16
In Stock
Furnace Gas Valve (replaces 0151m00013s) B1282628
#211

Burner box assembly diagram

Furnace gas valve (replaces 0151m00013s)

Part #B1282628

$114.39
9% OFF Phone Price : $126.39
In Stock
Orifice B4089343
#201

Burner box assembly diagram

Orifice

Part #B4089343

Replaced by #0163F00018

?
Manufacturer substitution
This part replaces B4089343. Substitute parts can look different from the original.
This item is not returnable
In Stock
Shell 2539305
#221A

Blower assembly diagram

Shell

Part #2539305

Replaced by #2539305S

?
Manufacturer substitution
This part replaces 2539305. Substitute parts can look different from the original.
$86.06
7% OFF Phone Price : $92.06
In Stock

Symptoms for treadmills

Choose a symptom to see related treadmill repairs.

Main causes: no power, bad power cord, tripped or faulty overload switch, bad power switch, wiring failure, bad motor co…

Main causes: rear roller out of alignment, damaged walking belt, bad roller…

Main causes: missing safety key, bad control console, wiring failure, faulty motor control board, bad drive motor…

Main causes: faulty sensors, wiring failure, bad control console…

Main causes: bad control console, wiring failure, bad motor control board…

Main causes: damaged walking belt, improper belt tension, lack of belt lubricant, bad drive motor…

Main causes: damaged walking belt, improper belt tension, bad roller bearing…

Repair guides for treadmills

These step-by-step repair guides will help you safely fix what’s broken on your treadmill.

How to replace a treadmill motor controller

How to replace a treadmill motor controller

Your treadmill motor won't run with a defective motor controller. Replace the motor controller if it doesn't operate the…

Repair difficulty
Time required
 15 minutes or less
How to replace a treadmill walking belt

How to replace a treadmill walking belt

A worn walking belt will begin to slow down during use. If your treadmill walking belt is worn out, replace it using the…

Repair difficulty
Time required
 45 minutes or less
How to replace a treadmill drive motor

How to replace a treadmill drive motor

A defective drive motor won't run when activated by the motor controller. Replace the treadmill drive motor if it doesn'…

Repair difficulty
Time required
 15 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 treadmill.

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.…

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

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

Top questions about Sears and Sears PartsDirect

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