Sears Home Services
Sears Home Advantage
appointment lookup logoAppointment Lookup
telephone logo213-596-2538
RepairHome WarrantyTune-Up & MaintainFencingShop Parts
Resources
RepairHome WarrantyTune-Up & MaintainFencingShop PartsResource CenterGlossaryHelp
sears home advantageSears Home Advantageappointment lookup logoAppointment Lookup

Table of Contents

What Is a Potentiometer?

How Does a Potentiometer Work in an Oven?

Key Benefits of Potentiometers in Ovens

Potentiometers vs. Digital Controls: Why They Still Matter

Maintenance Tips for Oven Potentiometers

  1. Resource Center
  2. Repair

How Does a Potentiometer Work?

6 min readUpdated Nov. 21, 2024Lyle WeischwillOvenAppliance 101
Title image for blog article "How Does a Potentiometer Work?"

Modern appliances, including ovens, rely on advanced components for precise operation. Among these is the potentiometer, a versatile device that plays a crucial role in temperature control and user interface functionality. If you’ve ever adjusted the temperature knob on your oven, you’ve directly interacted with a potentiometer. But what exactly is it, and how does a potentiometer work? Read on to find out.

KEY TAKEAWAYS

  • A potentiometer is a variable resistor that adjusts voltage by moving a wiper along a resistive element. In ovens, it allows users to set precise temperature levels by modulating resistance, enabling accurate and consistent heating essential for cooking tasks like baking and roasting.
  • Potentiometers are cost-effective, durable, and simpler to repair or adjust compared to digital systems.
  • Regular cleaning and inspection of potentiometers can extend their lifespan. Calibrating the potentiometer helps maintain accurate temperature settings, with simple adjustments possible for offsets within ±35°F.

What Is a Potentiometer?

A potentiometer, often referred to as a "pot," is a three-terminal device that acts as a variable resistor or voltage divider. It consists of:

  • Resistive Element: A strip of material (such as carbon or a composite) with a uniform resistance.
  • Sliding Contact (Wiper): A movable arm that glides along the resistive element.
  • Terminals:
    • Two fixed terminals connected to either end of the resistive element.
    • One terminal connected to the wiper, which adjusts the resistance.

By moving the wiper, you can change the resistance or voltage output, making the potentiometer ideal for controlling variables such as temperature or light intensity.

How Does a Potentiometer Work in an Oven?

In ovens, the potentiometer is often integrated into the temperature control knob. Here's how it works:

  • When you turn the knob, the potentiometer’s wiper moves along the resistive element, altering the resistance.
  • This change in resistance adjusts the voltage supplied to the oven’s control system, which interprets the signal and modulates the heating elements accordingly.
  • Set the pointer on the potentiometer knob to the desired temperature scale position that surrounds the knob on the control panel. The control panel in some ovens provides a digital display of the potentiometer temperature setting.

The potentiometer give you precise control of the oven temperature setting.

Key Benefits of Potentiometers in Ovens

Precision

Potentiometers enable fine adjustments to the oven’s settings, allowing for exact temperature control—essential for baking and roasting.

Durability

High-quality potentiometers are robust and can withstand the repetitive motions of everyday use, as well as the heat and vibrations present in an oven's environment.

Simplicity

Unlike more complex digital controls, potentiometers are straightforward to use and repair, making them cost-effective and reliable.

Potentiometers vs. Digital Controls: Why They Still Matter

With the rise of digital touchscreens and programmable controls, you might wonder why potentiometers are still in use. The answer lies in their simplicity and reliability.

  • Cost-Effectiveness: Potentiometers are cheaper to produce and integrate than advanced digital systems.
  • Ease of Repair: A faulty potentiometer can often be replaced without the need for complicated and difficult diagnostics.
  • Tactile Preference: Many users prefer the analog feel of turning a knob, especially for tasks like baking.

Maintenance Tips for Oven Potentiometers

To keep your oven's potentiometer in good condition, follow these expert tips.

Maintenance and Cleaning

  • Clean Regularly: Dust or grease can accumulate on and around the knob, interfering with smooth operation. Use a soft cloth and mild cleaner to wipe it down. Follow any additional instructions provided in your oven’s user guide to keep the potentiometer clean.
  • __ Inspect the Knob:__ Check for cracks, damage, or excessive play in the knob. Replace the knob if it’s loose or damaged.
  • Replace the Potentiometer When Necessary: If the potentiometer becomes unresponsive or erratic, schedule oven repair service to have a service technician install a new one.
  • Schedule Professional Oven Maintenance: To keep your oven and the potentiometer in top shape and working properly, schedule professional oven maintenance yearly.

Calibrating or Adjusting the Potentiometer

Over time, the temperature setting on your oven can drift away from the factory setting. When this happens you'll find that your oven consistently bakes or roasts food faster or slower than the time specified in the recipe.

Fortunately, you can recalibrate your oven temperature potentiometer to get it closer to the original accurate setting.

First, find the oven’s average temperature

To know how much to adjust the temperature, you’ll need to know how far off your oven’s actual average temperature is from the temperature you set.

You’ll need an accurate oven thermometer for this task.

Because the oven temperature rises and falls around the set temperature as the element or burner cycles on and off, you’ll need to record oven thermometer readings several times to accurately determine actual oven temperature. The more readings you take, the more accurate the average you calculate will be (oven repair technicians often take at least 5 readings).

Follow these steps to accurately find the actual oven temperature:

  1. Put the oven thermometer on the middle rack and set the oven to 350 degrees.
  2. Let the oven preheat and then wait at least 10 minutes more for the temperature to level out from the preheating temperature spike.
  3. Check the oven thermometer reading by looking through the oven window and record the temperature on a sheet of paper.
  4. Wait 10 minutes and record another oven thermometer reading. Continue taking several more readings every 10 minutes.
  5. After recording the actual temperature readings from the oven thermometer, add the readings and divide by the number of readings you took to determine the actual oven temperature.

Set the temperature offset to make up for the difference

The difference between 350 degrees F and the average temperature you measured is the offset you'll set to recalibrate the oven potentiometer.

For example, if the average was 330 degrees F, the offset is +20 degrees; if the average was 380 degrees F, the offset is -30 degrees.

You can adjust most oven potentiometers by about 35 degrees in either direction. If the average temperature off by more than 35 degrees, you may need to replace the potentiometer.

Here are instructions for adjusting the potentiometer in common types of ovens. The exact steps vary by manufacturer, so check your owner's manual for instructions for your model.

  1. Pull off the temperature control knob.
  2. On the back of the control knob you’ll find small adjustment screws and a pointer in a track. The back of the knob may be labeled Cooler at one end and Hotter at the other.
  3. Loosen the screws just enough that you can move the pointer.
  4. Move the pointer toward Cooler if the oven overcooks or Hotter if it undercooks. Each audible click adjusts set temperature about 10 degrees.
  5. Tighten the screw and replace the knob.

Here’s an image to illustrate the temperature adjustment:

how-to-calibrate-a-potentiometer

Repeat the process for checking the actual average temperature. Continue adjusting the potentiometer until actual average oven temperature matches the set temperature on the potentiometer.

If you’re unable to calibrate the potentiometer on your own, schedule appliance repair service and we’ll send a Sears Home Services technician to your home to adjust the temperature or replace the potentiometer for you.

Understanding how a potentiometer works and how to adjust it when necessary can help your baked goods to turn out perfect every time.

At Sears Home Services, we’re always standing by to help you get the most out of your oven and all of your home appliances. Trust us for all of your home maintenance and repair needs.

Schedule your oven repair now!

Trust the expertise of our technicians to diagnose and repair any oven issue, no matter where you bought it.

Call (213) 596-2538 or schedule online now.
Text (240) 616-1772 to schedule now.

Was this information helpful?

Schedule your oven repair now!

Text (240) 616-1772

Repair Oven Resources

Title image for blog article "How Does a Gas Oven Work?"
8 min readNov. 22

Learn how a gas oven works and get tips on how to safely use it.

A woman baking cookies in her convection oven.
8 min readNov. 14

Explore how a convection oven works to cook food faster and more evenly. Learn the benefits, best practices, and maintenance tips to get perfect results every time.

After calibrating an oven, a father and his children happily make holiday cookies together.
9 min readNov. 14

Learn how to calibrate oven temperature accurately for perfect cooking results every time.

Image showing a homeowner dealing with an oven door that won't close
6 min readOct. 21

If your oven door won't close properly, it can lead to issues such as heat loss and uneven cooking.

Glossary Terms

A thermocouple is a sensor used for measuring temperature, consisting of two different metal wires joined at one end, which generate a voltage proportional to temperature changes.

An oven bag is a heat-resistant, nylon or polyester bag designed for cooking a wide variety of foods in the oven, ensuring moist and flavorful meals by trapping moisture and flavor inside.

An oven rack is a removable shelving unit inside an oven that holds cookware, allowing air to circulate around the food for even cooking and baking.

A furnace is a major appliance that heats air distributed throughout a home or building via a ductwork system.

Common Repair Oven Symptoms

The most common reasons your Whirlpool oven won't turn off are a defective electronic control board, dead power supply or a bad control thermostat.

The most common reasons your Whirlpool oven won't light are a defective electronic control board, defective control panel or a cracked igniter.

The most common reasons your Whirlpool oven won't heat up are a cracked igniter, defective electronic control board or a defective control panel.

The most common reasons your Whirlpool oven stopped working are a defective electronic control board, cracked igniter or a damaged fan motor.

The most common reasons your Whirlpool oven is not working are a defective electronic control board, cracked igniter or a bad control thermostat.

The most common reasons your Whirlpool oven is not turning on are a defective electronic control board, defective control panel or a dead power supply.