An oven taking too long to preheat may be completely normal for its size and settings, or it may have a weak igniter, a failed element or a leaky door. A simple oven thermometer and a few observations will tell you which.
In this post:
- •That's how long your oven takes
- •Extra mass is inside
- •An electric element has failed
- •A gas igniter is weak
- •The temperature sensor is off
- •The door gasket leaks heat
- •Your building supplies lower voltage
1. That's how long your oven takes
Many ovens take longer to preheat than people expect, especially at high temperatures or on convection settings.
How to tell: The time hasn't changed since the oven was new. Many ovens also beep "ready" before the whole cavity is evenly hot.
What to do: Check your manual for preheat guidance before assuming a fault. On convection ovens, a slow convection preheat can also come from the fan or its element; see why a convection fan stops working.
2. Extra mass is inside
Pizza stones, cast iron and extra racks soak up heat before the air can reach temperature.
How to tell: Preheat is slow only when the stone or pans are in.
What to do: Expect the extra time, or take out racks and pans you don't need.
3. An electric element has failed
Many electric ovens use both the bake and broil elements to preheat. If one is out, the other carries the load slowly.
How to tell: The broil element doesn't glow on broil, or the visible bake element has a blister, break or dark section. Some bake elements are hidden under the oven floor.
What to do: Book a technician to test and replace the element.
4. A gas igniter is weak
In many gas ovens, the glowing igniter must reach a certain current before the gas valve opens. Weak igniters take longer, and some never light the burner at all.
How to tell: A long pause between the igniter glowing and the burner lighting.
What to do: This is gas equipment, so leave it to a professional.
5. The temperature sensor is off
The sensor probe at the back of the oven tells the control when to stop heating. If it reads wrong, preheat ends early or drags on.
How to tell: An oven thermometer on the center rack disagrees with the display by a wide margin after 20 minutes.
What to do: Have the sensor and control tested. Some ovens allow a small temperature offset in settings; your manual will say.
6. The door gasket leaks heat
Heat that escapes around the door has to be made up by the elements or burner, so preheat takes longer.
How to tell: Heat escapes around the door edge, or the gasket is torn, flattened or loose.
What to do: Many gaskets clip in and can be replaced with the right part for your model.
7. Your building supplies lower voltage
Some apartment and condo buildings supply 208 volts instead of 240, and electric ovens heat more slowly on 208.
How to tell: Your building's electrical service is 208 volts. An electrician or building manager can confirm.
What to do: Check that your oven is rated for 208-volt use. Slower preheat is expected in that case.
When a technician is the better call
Any gas oven problem, failed element or sensor fault belongs with a pro. Our oven repair technicians work on gas and electric models.
Marco's advice: Time your preheat once when everything is working, and write it inside a cabinet door. When it starts taking noticeably longer, you'll know something changed, and you'll have a real number to give the technician.
Tired of waiting on the oven? Call ProFix LA at (818) 334-4526.