The shaded pole motors for fans or pumps in such equipment are very sensitive to wrong frequency.
I have yet to see any examples of that; the motor will merely run slightly faster which is not signifigant except for mechanical clocks, timeswitches and some turntables & tape decks. Most electronic clocks can be modified for 60Hz operation. If you look up the data for the IC used, there's usually a pin that gets tied high or low to select 50 or 60Hz operation. Clocks that are crystal controlled are not affected.
I've seen 220V 60Hz fridge compressors here that have worked for years without ill effects. If anything, going up to 60Hz for a 50Hz motor would probably stress it less than going the other way. Brush motors of course, don't care about frequency...even DC is suitable.
I would simply wire the required appliances across the two phases to obtain the 240V.
