justwondering

can I install a 40 amp oven to an exisitng 50 amp breaker or should I down size the breaker to a 40 amp

nealtw

The 50 amp breaker is there for the wire and the oven has it's own fuses or breakers.

kok328

You MUST downsize the breaker, you can not over protect the appliance.
If the appliance is rated at 40amps and it starts to draw excess of 40amps, the breaker must trip to protect the circuit as well as the appliance.