6045 and 6025 both throwing propeller

[bondolo]

I replaced my random assortment of old powerheads with Tunze nanostream models last spring and now several of them are throwing off their propellers after a couple minutes or hours of being powered on.

Is this a known issue? I have seven of the units and three are now having this problem and possibly a fourth is developing it.

 

[rvitko]

This would be normal if they were used on a wave maker, the repeated start and stop impacts break the blades free of the magnet assembly, for this reason they should never be cycled on and off more frequently than once every 15 minutes and that only guarantees the props will last at least 2 years. Their is an impact on every start to correct the rotational direction, they want to spin backwards as it is the path of least resistance.