Problem with industrial geyser tank contactor

[AndyD]

Any other possible solutions?

Errm........ find the fault is the ony solution. If you have a neutral that's rising to 220v with respect to earth then the neutral is floating. If the neutral was in tact then it shouldn't ever rise more that a couple of volts above earth potential and even then that would be under heavy load conditions. You'll need to get your tester out and go find the neutral fault. If the neutral is floating at the point of supply back at the main DB then call Eskom or whoever the supply authority is and get them to sort it out on their side. If you're unsure on the testing proceedures then please get someone who is sure to assist you because Eskom will give you hell if you call them out and the fault is on the consumer side.

*Edit* I doubt the fault is on the supply side because other people in the flats would have complained by now, depending which phase they're on either they'd have zero volts L-N and nothing would be working or they'd have 380V L-N and their lights and appliances would have gone tits-up with a smell of burning by now.