The most common cause of an oven no longer heating up is a failed oven element or cooker element, replacing the oven element yourself in most cases is relatively simple and will cost a lot less than calling out a service engineer.
Safety First
First of all you should always unplug the device and ensure that there is no electricity supply reaching the appliance.
Remove your element
The next thing to do when replacing your cooker element is to remove the old one, first open the oven door and remove the back plate form inside the oven, these are held in by several screws which all need to be removed before you can pull the back plate out. You should now be able to see the cooker element or oven element and notice that there maybe some visual signs of wear and tear being the cause of your ovens heating problems although this is not always the case.
You should now also notice the screws that are holding the oven element in place, these will need to be removed to free the element from it’s position. Now disconnect the wires that are attached to the element but be careful not to let the wires fall into the appliance, if this happens it may take some time to find the wires and may require rear access to the appliance to relocate the wires.
Install the new element
Now the old faulty cooker element has been removed it is time to replace it with the new one. Again this is usually straightforward. Put the new element in to place and reinsert the screws and tighten them up. Reconnect the wires to the new element and make sure they are fixed tightly to the new cooker element. Put the back plate back into position and screw it up tightly, in some instance you will have to push the reset button if your cooker or oven is fitted with an RCD (circuit breaker)
Your appliance should now be ready for use but if further problems occur then it is worth calling out a service engineer to assist with fault finding and part replacement.
Locating the correct element
http://www.yourspares.co.uk/oven-elements
It’s easy to find the right element for your oven, grill or cooker, choose by selecting the manufacturer of your appliance and then either select or enter your model number. You may see that there is more than one element showing for your appliance so in these cases it usually means that there is a genuine and a pattern (non genuine) element available for your cooker. The genuine type is usually more expensive and generally of better quality than the pattern parts although the pattern ones are still excellent value and all are made to the correct specifications.