How Does a Gas Oven Work?
A gas oven is a staple in many kitchens, prized for its quick heating, precise temperature control, and even cooking. But have you ever wondered what happens behind the scenes when you turn the control dial or enter settings on the control panel?
Understanding how a gas oven works can help you use it more effectively and keep it running smoothly. Here’s a breakdown of the mechanics and features that make a gas oven tick.
KEY TAKEAWAYS
- Gas ovens use natural gas or propane as fuel, heating quickly with burners controlled by thermostats or sensors. Modern ignition systems like glow bar or direct spark provide reliable and safe operation, allowing precise temperature adjustments and consistent cooking.
- Gas ovens preheat faster than electric models, create a moist cooking environment ideal for baking and roasting, and offer immediate response to temperature changes. Additionally, they can be cost-efficient depending on local energy prices.
- Regular cleaning of burners, inspection of ignition systems, and annual professional maintenance ensure optimal performance and longevity. Proper ventilation and monitoring for gas leaks are essential for safe operation.
The Basics of a Gas Oven
At its core, a gas oven uses natural gas or propane as a fuel source to produce heat. When you turn on your oven, gas flows to the burner, where it is ignited to generate heat.
This heat is distributed throughout the oven cavity to cook your food evenly.
Gas ovens typically consist of these key components:
- Burners: These components provide the flame that heats the oven. The main burner is located at the bottom of the oven, and in some models, an additional broiler burner is situated at the top of the oven cavity.
- Thermostat or Temperature Sensor: The themostat monitors and regulates the oven's internal temperature by controlling the gas flow to the burner. In an oven that uses an electronic control board, the temperature sensor detects the temperature inside the oven cavity and sends the temperature signal to the electronic control board so the board can properly maintain the set oven temperature.
- Ignition System: Modern ovens use electronic spark ignition or a glow bar igniter system to safely ignite the gas.
- Ventilation System: Vents allow excess moisture and gases to escape the oven cavity as hot air expands inside the oven, ensuring safe operation and optimal cooking results.
Step-by-Step: How a Gas Oven Works
1. Turning On the Oven
When you set your desired temperature and turn the control knob on, the thermostat sends electric current to the igniter to start the oven.
If you have an oven with an electronic control panel, the electronic control board will activate a relay and send current to the ignition system to light the burner.
2. Burner Ignition
For safety, pilot light ignition systems have been phased out of gas ovens over the years. Almost all oven models now use a glow bar ignition system or a direct spark ignition system. Here are descriptions of how these ignition systems work:
Glow Bar Ignition System
This type of ignition system is by far the most prevalent in today’s gas ovens. It is a safety-enhanced method for igniting the oven burner. It uses an electric heating element, the glow bar, to light the burner without requiring a continuously burning pilot light.
Here's how it works step-by-step:
- Activating the Glow Bar: Electric current flows from the control to the igniter glow bar when you turn the oven on. The igniter heats up and glows to ignite the burner when the safety gas valve opens. For safety, the gas valve in the ignition system won’t open until the glow bar gets hot enough to ignite the gas and allows enough electrical current to flow downstream to the current-activated switch on that device.
- Opening the Gas Valve: As the glow bar igniter heats up, its electrical resistance decreases to allow more current to flow to the safety gas valve. Once the igniter glow bar is so hot that it allows more than 3 amps of current to the safety gas valve switch, the bi-metal switch on the safety gas valve trips. This opens the gas valve and gas flows to the burner tube and ignites.
- Cycling of the Burner: The glow bar igniter continues to glow as the burner flames heat the oven. When the oven reaches the set temperature, the control shuts off current to the igniter and safety gas valve. The burner shuts off and stays off until oven temperature decreases about 10 degrees below the oven temperature set point. Then the ignition process repeats to light the burner and maintain the set temperature.
This ignition system is reliable and safe because the safety gas valve will never open unless activated by enough current because the glow bar igniter is hot enough to light the burner.
Direct Spark Ignition System
The direct spark ignition system is controlled by an electronic circuit board. When you set the oven controls on the control panel to start the oven, the direct spark ignition circuit board begins this ignition process:
- The control board sends current to the spark electrode and gas valve to ignite the burner.
- Gas flows through the oven burner tube and the igniter electrode sparks to light the gas.
- The flame heats the flame sensor and the burner heats up the oven to the set temperature. If the flame sensor doesn’t detect a flame, the system shuts the gas valve for safety.
- Once the oven heats to its set temperature, the control shuts the gas valve so the burner goes out. When the oven temperature decreases about 10 degrees below the set point, the ignition process repeats to maintain oven temperature at the chosen setting.
This ignition system is also safe and reliable. The gas valve won’t stay open unless the system detects a burner flame.
Oven Heating
The burner produces a steady flame to heat the oven. Heat rises naturally and spreads throughout the oven cavity, cooking the food.
The thermostat or temperature sensor continuously monitors the oven temperature. The control cycles the oven burner off and on as described in the ignition descriptions above to maintain the set oven temperature.
Ventilation
Air inside the oven cavity expands as it heats. Excess moisture and combustion byproducts are vented out of the oven through openings in the oven door and the front of the oven body, ensuring even cooking and a safe environment.
Advantages of Using a Gas Oven
Quick Preheating
Gas ovens heat up faster than electric ovens because they generate heat directly from the flame.
Moist Cooking Environment
The combustion process releases moisture, which can help prevent foods from drying out—ideal for baking and roasting.
Precise Temperature Control
Adjusting the oven temperature will result in quicker response in a gas oven.
Also, the gas flame provides more immediate and precise heat level adjustments to consistently maintain baking temperature at the chosen setting.
Cost Efficiency
Depending on energy prices in your area, natural gas or propane can be more economical than electricity for cooking.
Common Features of Gas Ovens
- Broiler Function: A broiler, located at the top or in a separate drawer, uses high-intensity heat for tasks like browning or crisping.
- Self-Cleaning Mode: Some gas ovens offer a self-cleaning feature that burns off food residue at high temperatures, reducing cleaning efforts.
- Convection Settings: Modern gas ovens may include a convection fan to circulate heat, ensuring even cooking.
Gas Oven Maintenance Tips
Keep Oven Burners Clean
Food debris can clog burners and affect performance. Clean them regularly with a damp cloth and mild detergent.
Check the Ignition System
Ensure the glow bar igniter or direct spark ignition system is functioning correctly. If you notice delays or failures in ignition, schedule oven repair and we’ll send a Sears Home Services technician to your home to fix the problem.
If you have an oven with a glow bar igniter, we have some advanced DIY troubleshooting to offer. Follow the steps in this popular video to learn how to fix your oven when it won’t ignite:
If you’re unable to determine the cause of your oven heating problem after following the advice in this video or you get to the point where you need to have a professional fix the ignition issue, schedule oven repair service and we’ll resolve the problem for you.
Professional Maintenance
Schedule professional oven maintenance every year. A qualified service technician will visit your home and perform these essential oven maintenance, inspection and cleaning tasks:
- Inspect gas supply connections.
- Check the ignition system.
- Inspect oven burners and clean them if needed.
- Examine oven flames and adjust the flame settings if necessary.
- Check the overall oven performance.
- Inspect readily accessible electrical wiring.
- Level the oven if necessary.
Annual professional maintenance won’t just ensure that the oven works safely and efficiently, it will also help your appliance last longer.
Safety Tips for Using a Gas Oven
- Ensure Proper Ventilation: Gas ovens release carbon monoxide during combustion. Use the range hood or keep windows slightly open while cooking.
- Check for Gas Leaks: If you smell gas, turn off the oven immediately, ventilate the area, and contact your gas company or technician.
- Avoid Overloading: Overcrowding the oven can block heat circulation, leading to uneven cooking.
Follow the tips in this helpful video to position and use oven racks properly:
A gas oven is a versatile and efficient appliance that remains a favorite among home cooks and professional chefs alike.
By understanding how it works and following simple maintenance and safety practices, you can maximize its performance and enjoy perfectly cooked meals for years to come.
Schedule your oven repair now!
Trust the expertise of our technicians to diagnose and repair any oven issue, no matter where you bought it.
Was this information helpful?
Repair Oven Resources
Learn how a potentiometer works in an oven and how to adjust it if necessary.
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.
Learn how to calibrate oven temperature accurately for perfect cooking results every time.
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.