How To Test Cooker & Oven Elements Using OHM’s Law Calculator?

Cooker Oven Guide: Testing Elements Using Ohm's Law

In this guide, we will show you how to use Ohm's law to test elements in a variety of ways. You can use the resistance value in ohms to determine the wattage of an element, or you can use the wattage of the element to figure out what the resistance should be. If you have a test bay or a test meter, you can also use the appliance's ampage draw to determine the resistance value or wattage of the elements.

We would recommend you watch our video since we're showing related components and possible problems with testing the cooker oven elements.

Additionally, you can visit our web store to buy genuine spare parts: https://shop.how-to-repair.com/collections/cooker-oven-parts

Understanding the Oven Elements

This guide will utilize a dissected oven for demonstration purposes. It's important to understand the combinations of elements within the oven. On a fan oven setting, you would be using a fan oven element in conjunction with the fan motor to distribute air around the oven. On a convection oven, you would be using a combination of a part of the grill element with the base element, which is located in the oven's cavity and usually not visible.

Using the Ohm's Law Calculator

The Ohm's law calculator is a useful tool for testing elements. To use the calculator, you'll need a base voltage (we'll be using 230 volts, which is stamped on all elements), and you'll need to fill in one of the other three fields.

For instance, ohm's law relates voltage (V), current (I), and resistance (R) in an electrical circuit: V = IR. To test oven elements, you'll need a base voltage, typically 230 volts for UK appliances.

Example 1: Testing with Known Wattage

1. Example Element: 1800-watt element.
2. Calculation: Using the Ohm's Law calculator, input 1800 watts and 230 volts to find the resistance.
3. Result: The resistance should be approximately 29.38 ohms, allowing for a 10-15% margin of error due to the multimeter accuracy and element age.

Example 2: Testing with Known Resistance

1. Example Resistance: 63.7 ohms.
2. Calculation: Input 63.7 ohms and 230 volts to find the wattage.
3. Result: The element should draw about 830 watts. The tested element drew 850 watts, within the acceptable margin of error.

Example 3: Testing with Current Draw

1. Example Current Draw: 8.7 amps.
2. Calculation: Input 8.7 amps and 230 volts to find the combined wattage.
3. Result: The appliance draws 2001 watts, indicating the element is around 1800 watts and other components (e.g., timer, fan motor) draw about 201 watts.

Testing Individual Components

The most common element to fail on all cookers, whether freestanding, built-in, or range cookers, is the fan oven element. This element, usually rated at 230 volts and 1800 watts, is situated at the rear of the cooker. The fan motor circulates air from this element around the cooker, with the thermostat at the top controlling whether the element is on or off. More modern cookers use NTC sensors and a circuit board to control this, and sometimes the relays can fail.

To test the element, you can use any of the methods described above. Understanding these different ways of testing is crucial for diagnosing and fixing oven faults.

Grill Elements and Convection Ovens

Grill elements and convection ovens may use part or all of the grill element in conjunction with the base element. We have a single Grill element in the video, rated at 230 volts and 2000 watts. An ohms reading on this element shows 26.5 ohms, indicating that the wattage on this element is 2000 watts.

There's also a dual grill element with two circuits: an inner circuit and an outer circuit. Typically, the outer circuit is used in conjunction with the base element for convection ovens. This element is stamped with 900 watts for the outer circuit and 1300 watts for the inner circuit. If we test the outer circuit, we get a reading of 59.6 ohms, indicating it's 900 watts. Testing the inner part gives us a reading of 40.4 ohms, indicating it's 1300 watts.

We suggest you to watch our video to learn how to test these elements.

Why Cooker Oven Elements Fail?

Elements often fail due to becoming an open circuit, which means electricity is going to the element but no power is being drawn. This results in no heat coming from the element. Alternatively, the element may have earth leakage, where the electricity is tracking from the inner part of the element to the outer part, causing the electricity supply to trip.

Understanding these different ways of testing is crucial for diagnosing oven faults. If you need any elements for your cooker, please visit our website and enter your full model number.

If you can't find the part, please contact us with your full model number and serial number from your cooker, and we'll be happy to help.

To do a calculation on an element, we use this site: https://ohmslawcalculator.com/ohms-law-calculator

If you need any parts for your cooker and oven, you can find them on our site.

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