Update ....

Still not working but I'm now pretty sure I have got the wiring correct.
I've had a close look at the old element and the spade terminal does show
that Feed 2 did have two wires connected to it. So I'm pretty convinced I
do have it wired correctly.

Symptoms are that when turned on, the dryer will run for about 5 minutes and
will then trip out the RCCB. Icannot reset the RCCB with the dryer still
switched on. If I switch off the dryer I can reset the RRCB but as soon as
I switch the dryer back on the RCCB trips.

If I leave the dryer to stand for 10 minutes or so, I can start the dryer
but it will trip shortly after.

Sounds like something is overheating (or thinks it is overheating). The
circuit breaker isn't tripping so this brings me back to the other
sensor/fuse (the oval device screwed to the back).

Could this be the cause?

Anyone know what it is?

Cheers,

Nigel