What is an infinite switch?

An infinite switch is a rotary switch that provides continuous variable control over the power delivered to a heating element. This allows users to precisely adjust the heat output of a burner or element, offering a wide range of settings between minimum and maximum.

Can I repair an infinite switch?

Infinite switches are typically sealed units and are not designed for repair. If a switch is malfunctioning, the recommended solution is usually to replace the entire component rather than attempting to fix internal parts. Attempting repairs could be unsafe and ineffective.

Why is it called an 'infinite' switch?

It's called an 'infinite' switch because it offers a seemingly infinite range of heat settings between minimum and maximum, rather than discrete, stepped settings. It modulates power delivery by varying the 'on' time of the heating element over a cycle, providing fine control.

Oven Infinite Switch Repair Guide

Appliance Aid takes part in the Amazon Associates programme. Some links on this page are affiliate links, and a qualifying purchase earns us a commission. Your price is unchanged.

🏆 RECOMMENDED PART

Bosch 12038730 Microwave Switch Kit

The Bosch 12038730 Microwave Switch Kit is also called a Switche Group Service Kit which contains the Right Hand & Left Hand Switch Holder, 1 Monitor Switch, 2 Door Switch, and 1 Lever Pre-Installed
The Bosch OEM Part 12038730 is quality tested and Bosch approved. The replacement part is a new Bosch part that doesn't replace any other part
The Bosch 12038730 is a genuine Original Equipment Manufacturer (Authentic OEM) part from Bosch that fits perfectly with various models from the following Microwave brand(s): Bosch, Thermador
The Bosch Part 12038730 includes one 20amp fuse. This brand new Bosch part is an authorized OEM part; perfect for repairs and replacements
The microwave shielding and interlock switches must be properly tested following the door interlock switch replacement, a service technician should install this part. It is recommended to either refer to your applianc...

Check Price on Amazon

What the 12038730 does

The infinite switch controls the power supplied to a surface heating element, allowing for variable heat settings from low to high. It modulates the 'on' time of the element to achieve the desired temperature.

Symptoms when this part fails

Heating element stuck on one setting
Element not heating at all
Element heating continuously
Control knob turns freely without resistance
Burning smell from control panel area

Compatibility

Fits the Bosch family. Specifically:

Any unit originally equipped with OEM part number(s): 12038730.
Check the model/rating plate inside your appliance and compare it against the fitment table on the product listing before ordering — this guide does not list specific compatible models because Amazon does not provide verified fitment data through this pipeline.

Tools you'll need

Screwdriver (Phillips and/or flat-head)
Nut driver set
Needle-nose pliers
Wire strippers (if wiring needs repair)

Difficulty: Moderate · Time: 30-60 minutes

How to install the 12038730, step by step

Disconnect power to the oven at the circuit breaker.
Remove the control panel knobs.
Unscrew and carefully pull the control panel away from the oven.
Note or photograph wire connections to the old switch.
Disconnect all wires from the old infinite switch.
Remove the mounting screws securing the old switch.
Install the new switch, reattach wires, and secure mounting screws.
Reassemble the control panel, replace knobs, and restore power to test.