My RCD protected CU trips the RCD during thunderstorms. It was replaced during recent extension work as the old one (allegedly) tripped too slowly. This CU serves all rings and power (lighting is on a second unprotected CU) and one day this will happen when I'm on holiday which will be great for my freezers. We have a PME earth system and properly installed rings (no spurs) etc. How can I avaoid having to install dedicated fridge/freezer circuits to the non-rcd CU. PS my meter is rated at 45A. I recon I draw a tad more than that. Should I worry?