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Whirlpool
Countertop Microwave

Model # MT4078SPB0 Official Whirlpool countertop microwave

Here are the diagrams and repair parts for Official Whirlpool MT4078SPB0 countertop microwave, as well as links to manuals and error code tables, if available.

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Installation guide
Owner’s manual

Model diagram and schematic

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ALL PARTS
Showing 10 of 44 parts  |
Fan Blade 8184292
#1

Oven interior parts diagram

Fan blade

Part #8184292

$36.16
In Stock
Support 4359723
#8

Oven cavity parts diagram

Support

Part #4359723

$41.73
In Stock
Button Plug 4358857
#5A

Oven cavity parts diagram

Button plug

Part #4358857

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

Transformer 8205485
#4

Base plate parts diagram

Transformer

Part #8205485

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

Cap Fuse 8205483
#18

Oven interior parts diagram

Cap fuse

Part #8205483

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

Microwave Under-the-cabinet Installation Kit W10206556
#(NI)

Base plate parts diagram

Microwave under-the-cabinet installation kit

Part #W10206556

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

Screw 4358883
#10

Control panel parts diagram

Screw

Part #4358883

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

Air Duct 8205484
#12

Oven interior parts diagram

Air duct

Part #8205484

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

Installation Instructions 8204864
#1C

Door parts diagram

Installation instructions

Part #8204864

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

Control Panel 8205471
#5

Control panel parts diagram

Control panel

Part #8205471

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

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