6 mm

In brief: my house has an oven circuit with a 6mm cable and a 20 amp MCB. Both the electric hob (6.5 kW) and oven (2.8 kW) are on this circuit. Can I upgrade the MCB to stop it tripping? Background: We moved in to the house a couple of years ago. The built in oven was slow to heat up so I did a...