As I remember, the C210 cartridges have a lower heater resistance (about 2 ohm) than the C245.
At 12V, the peak power is about 72W. With 24V, that would be 4 times that: 288W.
They will sure heat up very fast (they already do at 12V), but that's clearly completely out of spec. I don't know what damage it can do. I doubt this unit is capable of delivering 288W anyway, so with C210 cartridges it probably limits the current anyway and so they'll never see 24V in practice. The max rated power of this unit will tell you.