Oven will not heat up. ?

I have a NEF U1442O DOuble Oven. The fan element stopped working and I bought a new one. I fitted this and it heated up but each time I put it all back together it tripped my house electrics. So i took off the back, fed the element contacts through, connected the wires and put it all back together. I do not get the electrics tripping any more but the oven will not heat up at al. None of the elements top, bottom or fan heat up

Please help Me !