Range cooker Oven will not turn onwhat to check
On most range cookers the ovens will not heat until the clock has been set, and the timer has to be in manual mode. Three manufacturers publish this themselves.
Before you start
What is the timer display doing?
The right answer depends on what you can see. Pick the one that matches.
Choose the option on the left that matches what your appliance is doing, and the answer for that case appears here.
What is the timer display doing?
The clock has lost the time, almost always after a power interruption. The oven is being held off deliberately until you set it.
Set the time of day, then try the oven again before doing anything else.
What is the timer display doing?
The programmer is waiting for a start time rather than letting you cook now. This is a separate problem from an unset clock and setting the clock will not fix it.
Switch the programmer to manual mode and the oven will respond normally.
What is the timer display doing?
The oven timer child lock is on. It is a different control from the hob child lock, and clearing one does not clear the other.
Hold the relevant timer key until the padlock symbol disappears — about ten seconds on the touch timers, three to five seconds on the plus button of the older programmer.
What is the timer display doing?
This is a supply problem rather than a setting. Smeg publish the check: the mains supply, and whether the switch upstream of the appliance is in the on position.
Check the cooker switch on the wall and the breaker in the consumer unit before assuming the appliance has failed.
What this means
This is the most common range cooker complaint that is not a fault, and it is worth ruling out before anything else because it costs nothing and it accounts for a great many call-outs. Most range cookers with an electronic programmer will refuse to run the main oven until the time of day has been set. Cut the power for any reason — a brief outage, a tripped breaker, an electrician working in the kitchen, or simply switching the cooker off at the wall while you were away — and the clock resets and starts flashing, and the oven quietly does nothing. There is no code, nothing has failed, and the cooker looks entirely healthy.
Three of the manufacturers in this category publish it in their own words. Glen Dimplex tell Stoves and Belling owners that if the timer display is flashing, the correct time of day will need to be set before the oven will function. Leisure put it even more bluntly on their support pages: if the timer is not set, the ovens will not work, and their all-gas Cookmaster book goes one further, listing an unset time as a published cause of there being no ignition spark at all. Smeg approach the same problem from a different angle and tell you to check whether the function knob has been set at all.
There is a second condition on the Glen Dimplex cookers that catches people who have already set the clock. The programmer also has to be in manual mode, usually shown by the word Man in the display, and the main oven will not operate while the programmer is set to Auto. A cooker that was set to come on automatically for a Sunday roast three months ago can still be sitting in Auto, waiting for a start time that has passed.
And on a multifunction oven, setting the clock is not enough on its own. You also have to choose a cooking function and set a temperature. An oven with the clock correct, the programmer in manual and no function selected will sit there lit and cold.
What causes it
| Cause | What is actually happening | How likely |
|---|---|---|
| The clock has never been set, or has reset after a power cut | A flashing timer display is the tell. Until the time of day is entered, the programmer will not release the oven, and a power interruption of any length puts it back into that state. | Common |
| The programmer is in Auto rather than manual | Glen Dimplex publish this as a separate condition from the clock. Their wording is that the main oven will not operate if the programmer is set to Auto, and manual mode is normally indicated by the word Man. | Common |
| No cooking function or temperature has been selected | On a multifunction oven the function knob and the temperature are two more gates in front of the element. Smeg list an unset function knob as a published cause of an oven that does not heat up. | Occasional |
| The cooker is not switched on at the wall | Worth checking properly rather than assuming. A range cooker is fed through a switch on the wall, and it is not always where you expect, particularly in a kitchen somebody else fitted. | Occasional |
| The appliance was bought ex-display and is in showroom mode | A shop-floor setting that keeps the control panel alive while disabling every heating element. Smeg publish this and the route out of it; most manufacturers in this category do not document it at all. | Rare |
What to try yourself
Look at the timer display. If any part of it is flashing, set the correct time of day first and then try the oven again. On many of these cookers that is the whole fix.
Check whether the display shows Man, or a symbol indicating manual mode. If it shows Auto, take it out of Auto — on Glen Dimplex timers with three physical buttons, pressing the two outer buttons together switches to manual, and on the three-key touch timers the middle menu key pressed twice does it.
Look for a padlock symbol. The oven timer has its own child lock, separate from the hob one. On the Glen Dimplex touch timers it is cleared by holding the middle clock key or the plus key for about ten seconds until the padlock disappears; on the programmer in their 2022 induction, dual fuel and all-gas books it is the plus button held for three to five seconds.
Select a cooking function and set a temperature. On a multifunction oven neither is optional, and the appliance gives you no indication that it is waiting for them.
If none of that works, switch the cooker off at the wall for a few minutes and back on, then set the clock again. Glen Dimplex publish this as their general reset and it is a reasonable last free step.
Get a qualified appliance engineer to look at your range cooker
We do not pass enquiries to a repair firm, so there is no form here. When you book a qualified appliance engineer, tell them the make, the model and the exact code or message on the display, and ask whether they carry parts for this make — that is what turns one visit into a repair rather than a quote.
What it costs to fix
Typical repair cost
£0
Time on site
10 minutes
Free. Every cause on this page is a setting rather than a part, which is why it is worth working through before booking anyone.
Typical UK prices including parts and labour, updated September 2026. Your quote may differ.
Own this appliance and had this code? . Nothing is published until a person has read it.
Related range cooker fault codes
- HUsually simple to fixH on a zone display means the glass above it is still hot enough to burn you. It is a warning rather than a fault, and every brand sets its threshold differently.Related: same brand
- Cooling fan runs on after cookingUsually simple to fixA range cooker fan that keeps running for up to an hour after cooking is designed behaviour, and the maker of Stoves and Belling tells you not to switch the cooker off to stop it.Related: same brand
- Gas oven goes out after a minuteGet it checkedA gas oven that lights and then shuts down within a minute is usually the flame supervision device, and three manufacturers publish the same sixty-second answer.Related: same brand
- U400Get it checkedA 400-family code means the cooker has been connected to the wrong supply or wired incorrectly. Five badges from four manufacturers publish a version of it, and it appears at installation.Related: same brand
- How to isolate a range cookerUsually simple to fixAn electric or dual fuel range cooker has no plug: five manufacturers describe a wall switch near but not above the cooker on a 30 or 32 amp circuit. All-gas ranges are the exception.Related: same brand
Related guides
Common questions
The grill and the hob work but the main oven does nothing. Is that still the clock?
Very often, yes. The programmer usually controls the main oven only, so the hob and the second oven carry on working and make it look as though one specific element has failed. That pattern is much more likely to be a programmer in Auto than a coincidence.
How long does the clock keep time in a power cut?
Not long. The one published figure is Glen Dimplex’s: the programmer in their 2022 induction and all-gas books maintains its status through a power loss of about a minute and a half, and they add that the key lock status and buzzer tone are remembered however long the power is off. Beyond that their advice is simply that after a power failure you should switch the supply off, switch it back on when the power returns, and reset the clock. Treat any interruption longer than a moment as having wiped it.
The oven light comes on but it never gets hot. Same thing?
Possibly, because on many of these cookers the light is on a separate circuit from the elements and proves nothing about whether the oven has been released to heat. Work through the clock, manual mode and the function knob first. If all three are right and it still stays cold, a failed fan oven element is the usual genuine cause, and the giveaway is that the grill still works perfectly.
Is there a fault code for this?
No. Not one manufacturer in this category publishes an oven fault code table of any kind, so an oven that will not start will never tell you why. That is exactly why the checklist matters more here than on an appliance that can talk to you.
Technical review
Not reviewed by an engineer
No engineer has read this page. Severity follows what the manufacturer publishes, and we would rather tell you that than let a byline imply a sign-off.
Sources and how we verified this
We establish the facts from the sources below and then write the explanation ourselves. We do not copy manufacturer wording and we do not host their manuals.
- Manufacturer technical and service documentation
- Manufacturer support portal
This page has not been reviewed by an engineer, and we would rather tell you that than imply otherwise. The severity rating follows what the manufacturer publishes: where they say isolate the appliance and call someone, so do we.