If the heat of your oven is leaking out, one possible cause could be worn out or broken door seal. These seals are designed to prevent the heat from escaping, allowing the oven to cook your food effectively.
Replacement Control Knob Aluminium Black for Baumatic Oven Hob Cooker
4 Baumatic Oven Cooker Hob Control Knobs Black & Silver Rotary Switch Dial Caple
Sharp Microwave Oven Door Hooks (Door Latch) - fits some models
2pcs Rectangular Microwave Oven Door Eject Button Easy Open Door Release Part
Beko Oven Door Hinge KDVF100S KDVF100X Left Or Right. (Price is per item)