Evidence grade: B1 — Trade practice
Oven no-heat starts with power and settings before anything inside the cabinet — tripped breakers, delayed-start, self-clean lockouts, and child locks cause a surprising share of "broken" ovens. From there the tree splits by fuel: electric ovens fail at elements and sensors; gas ovens fail at the igniter.
Effort: Easy–Moderate · 15–45 minutes · no tools for most checks; screwdrivers if you proceed to part inspection (unplug or kill the breaker first)
PPE and ventilation
Never open an oven cabinet while it's connected to power — for electric ovens, kill the dedicated breaker, not just the panel switch. Wear gloves against sharp sheet-metal edges. Normal room ventilation is sufficient; this is not a task for live-panel work.
Diagnostic tree
1. Is the display lit / does the oven have power? - No → Check the dedicated circuit breaker for a trip — a power surge can take out the 240V line while the rest of the house looks fine. Reset once; if it trips again → stop: call an electrician. - Yes → go to 2.
2. Is the oven in delayed-start, a self-clean cycle, or child lock? Any error code on the display? - Yes to any lock mode → Clear it per your manual. Self-clean and delayed-start lock out the heating elements by design [1]. - Error code shown → Look it up in your model's manual before doing anything else (this is where Repair Lab O24 helps). - None → go to 3.
3. Gas oven — do you smell gas, or do other gas appliances also fail to work? - Smell gas → Stop immediately. Leave, call the gas utility from outside. - No smell → go to 4. - (Electric oven → skip to 5.)
4. Turn the gas oven on and watch through the oven window or with the bottom panel open: does the igniter glow and the burner light within about 90 seconds? - Igniter glows but the burner never lights → The igniter is likely too weak to open the safety valve (they need to draw roughly 2.2–3.5 amps to open it). A weak igniter can't be repaired — it must be replaced, and gas ignition work is pro territory [1][2]. - No glow at all → Failed igniter or its power feed — call a pro [2]. - Burner lights → The no-heat complaint is likely calibration or airflow, not ignition.
5. (Electric oven.) Watch both elements during preheat: does the bake element (bottom) glow orange-red? Test broil separately — does the broil element (top) glow? - One element heats, the other doesn't → The dark element has failed; visible blisters, cracks, or dark breaks confirm it. A dead element must be replaced — element replacement with the breaker off is reasonable DIY with a model-specific part [1][2]. - Neither heats → go to 6.
6. Is cooking just slow or uneven rather than fully cold? - Slow preheat / uneven cooking → Suspect a struggling element, a drifting temperature sensor, or a failed convection fan — uneven results from these are common [2]. Temp sensors read roughly 1080 ohms at room temperature; a pro can confirm with a multimeter [1]. - Truly no heat at all → Possible blown thermal fuse (non-resettable, one-time safety device), failed control board, or internal wiring fault [1]. A blown fuse usually has a root cause behind it — call a pro rather than swapping the fuse blindly [2].
Stop rules
- Gas smell, delayed ignition "whoomph," or yellow lazy flames → stop and call for service. Gas combustion faults are never DIY.
- Burning smell, visible sparks, or a breaker that trips instantly when the oven starts → stop. That's a hazardous short; kill the breaker and call an electrician or appliance tech [1].
- 240V wiring diagnosis, control-board repair, and gas supply lines go to professionals. Do not work in a live oven cabinet, period.
Honest limits
- Self-clean cycles run hot enough to kill heating elements and blow thermal fuses — one trade source recommends avoiding self-clean as maintenance and cleaning with gentler methods [2].
- Element failure is the most common cause of electric oven no-heat, but "most common" isn't "yours": the settings checks in steps 1–2 eliminate the embarrassing free fixes first.
- Calibration exists for ovens that run consistently off-temperature (±35 °F adjustment is typical), but it's a delicate operation — one trade source recommends a professional for recalibration [2].
Sources
- Engineer Fix — "Why Isn't My Oven Heating Up? A Troubleshooting Guide" — https://engineerfix.com/why-isnt-my-oven-heating-up-a-troubleshooting-guide/
- Cody's Appliance Repair — "GE Oven Not Heating? Try This" — https://codysappliancerepair.com/blog/ge-oven-not-heating/
Repair Lab · Release 1 · Evidence last checked September 30, 2026 · A project of AOJEL