Cooktop and oven are running from 2 separate 30 amp circuits.
I want to replace both by a free standing dual fuel range which requires a 40 amp circuit
Can the 2 30 amp circuits be combined in the electrical outlet?
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Sign up to join this communityCooktop and oven are running from 2 separate 30 amp circuits.
I want to replace both by a free standing dual fuel range which requires a 40 amp circuit
Can the 2 30 amp circuits be combined in the electrical outlet?
No. While it might seem safe since each circuit is load-protected for it's gauge, you can have all kinds of problems.
First: Someone might work on the panel in the future and move a breaker and reverse the phase on one of the two circuits. This would cause a 240v short circuit.
Second: Any fault to ground will likely fault to only one of the two grounds which would be undersized for the fault load.
Third: Any difference in resistance in the two circuit hots will cause a difference in current in the two lines and cause nuisance tripping of one breaker.
Fourth: Any difference in resistance between the two neutrals will cause a difference in current that could overheat one of the two neutrals without tripping the breaker.
Fifth: As Ecnerwal points out, The appliance should trip at 40A, but if the current is balanced on both wires, the breakers may not trip until a combined load of 60A is achieved, causing a possible unsafe condition or damage to the new appliance.
No, nope, non, nyet, nein.
Check the wire gauge and number of wires you have. You'll need to feed this from ONE 40 amp breaker, but you may be able to use the existing wire if it's of adequate size and number of conductors. Otherwise plan on upgrading the wire as well...