Yes, a 240V circuit should either be fed from a two-pole breaker or two single-poles with a handle tie. If one non-grounded conductor is disconnected, so should the other.

Thanks. Would it be better to replace it with a two-pole 40 amp breaker, or just fine to add a handle tie to them?

Edit: It is a QO load center

It makes no difference really. The QO two poles (for regular breakers, not GFCI ) are little more than two single poles with a handle tie as it is.

Thank you. Another related question. Putting a new wall oven in to replace an old one (1994). I pulled out the old wall oven and opened the junction box for it. The connection to feed from the breaker panel uses some big connectors. See attached pic. They are difficult to untwist so I cut the wire from the old wall oven leaving a 6" tail for both the black and red. Can I connect the new wall oven black and red wires to these tails, or do I need to get those big wire connectors off the feed lines and connect to them and put those big connectors back on?

Chris- Get the old wire nuts off and toss the pigtails you created. The fewer spliced connections you have in this circuit the better.

Thank you,. Did that.

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