You don't need to worry about surge, I have a Deye 5K and 2 Dakin units that have 32A fuses each and they work fine they only used 16A each during the tests with 7 internal units running at full.
What could happen is this, I use Shelly Pro 4PM to measure the consumption and when I used the correct 30mA RCD it fired every time so I had to change it for an 300mA RCD, tomorrow I will receive RC / Snubber filters that should allow me to use the 30mA.
Probably the problem is in the relays of the Shelly because I'm sure the AC has a good filter.