Replacing a thermostat on a double door fridge?

HI there,
I have bought a new thermostat for my fridge.
I have 6 wires
2 green and yellow which are the earth and I know where they go.
Then I have
1 brown, 1 black and 2 white...
My thermostat has 3 numbers - 3, 4, 6
I have been told
brown to 3
black to 4 (this clip comes with a slot for 1 white) and
then I pressume the other white goes to 6???
My fridge boots up but runs and runs and is freezing up
Thanks