Print without a raft - nozzle too cool?

I am printing with generic ABS, with a raft temp of 100-110 C and a nozzle temp of ~230-250 C. I want to try printing models without a raft, but as soon as the nozzle performs the cleaning pass, the print pauses with a “Nozzle too cool” error, and I am forced to re-initialise the printer. However, the printer does not do this when printing with a raft. Any suggestions would be greatly appreciated.