What is a consumer unit?
Reasons to get a new fuse box
1) For electrical safety. Electricians will tell you that having a RCD is essential and is not usually present in older fuse boxes. It is a potential life saver as it can detect small leakage currents in the range 5-30mA and can disconnect the supply in less than 300ms which may prevent electrocution and injury. If your fuse box is more than 25 years old it may not have a RCD.
2) If your lights are flickering or your sockets are unresponsive, this could be a sign that your fuse box is deteriorating and may need upgrading.
3) If the fuse board has asbestos flash guards. Asbestos fibres are now known to be very harmful if breathed in. Asbestos was used on old fuse boards and would need replacing for new metal type instead.