Connecting Geyser to Deye Invertor

[Gordonza]

Hello there
I have a 8kw Deye, 10 x 545W panels and 2 x 5.12kw Shoto batteries. we have had weeks of issues from the grid, where we are without power for 7 days at a time (cable fault). my geyser is connected as non-essential, so don't get hot water when grid is down. I have just replaced the 4kw element with a 2kw element, and installed a change over switch so, if we having a sunny day and batteries are full, I can switch the geyser over to the invertor during the sun hours, however when I switch over I get a F18 over current error and the entire system goes down.
is a 2 kw element too much for the 8 kw deye?
any suggestions, thanks in advance

 

[timselectric]

It shouldn't be a problem unless you have a lot of other loads running.

 

[BentleyJ]

Just a guess. Its possible the heating element is a PTC type meaning you are getting a high initial surge current. You may be able to capture the PEAK current with a clamp on ammeter that has a Max Hold function. This test should be done using utility power.