I live in florida, you all know the temperature here is closer to hell than any other place. So even in my garage it gets hot especially the Controller, and it is only drawing 13.4 amps per leg on 220 volts.
Is it possible to add a small fan?
and what is the best place to put it and where would it be the air intake?
The only problem it will no longer be water proof.
Yes, it is likely the IO expander that controls the display is the issue. The temperature sensor is on the display module as well, it is part of the RTC clock chip. The sensor and IO chip are just a few mm from one another.
What is the maximum temperatur the Open V4 can tolerate? usually mine stay around 32 c (not charging), but some time with a hot day, rise to 65c (charging at 26amp) this is normal?
If it is too hot, they reduce the power itself?
The OpenEVSE v4 controller will tolerate temperatures to about 90C before its power supplies shuts down (internal PS temperature of 142C).
Temperature monitoring and throttling will slow down charging at 65C and shutdown if temperature exceeds 72C.
On my own "Advanced Series" station (see graphs below) at 32A (7.68kw) my normal temperature rise is 16C over the starting enclosure temperature. It is very hot where I live, my enclosure temperatures during the hottest months of the summer run from 34C - 44C.