Hi I have a 4year old Lamona 4601 double oven, the top oven/grill works fine but when I turn on fan oven it trips the power on the main house fuse board.

SOURCE: bottom oven not working

A tripped breaker or blown fuse on an electric oven or cook-top, combined with an element that has stopped working, is usually a sign of a shorted, then blown (if the fuse or breaker no longer fail) element.

If you know how to use an ohmeter, you can pull the element, disconnect the wires from each end, then measure the resistance between each end of the element, and each element to the outer sheath.

A good element has just a few ohms of resistance between the wire connection points, and infinite resistance from the wire connection points to the outer sheath. Any readings other than that means the element is bad and need's to be replaced.

SOURCE: indesit fde20 main oven wont heat up

sounds like the circular element at the back of oven has blown.

SOURCE: Top oven (and Grill) have stopped working

Hi,
If your electric oven is not heating then you probably have a bad heating element in your oven. This is not that hard to fix yourself...
Check out this tip that I wrote about the Oven not heating problem..

Oven Problems Electric Oven is Heating Slowly or Poorly
http://www.fixya.com/support/r4511800-oven_problems_electric_oven_heating

heatman101

SOURCE: The oven tripped the main fuse switch to the house

you have to set the clock befire anything works .if you have done that its could be that the element has failed and the fault current has damaged any of the contacts in the circuit which can be themostat ,timer contact thermal cut out contacts. failure of the timer contacts would leave nothing working

Testimonial: "Setting the clock worked a treat thanks for the advice "

SOURCE: hotpoint double oven

Have you tried holding the 2 left buttons in and pressing the + button