I see from the 250/100 datasheet:
Operating temperature -30 to +60 °C (full rated output up to 40 °C)
In our summer conditions, almost all MPPTs we have installed are too hot to touch.
We are collecting thermal imaging to provide examples, but in some cases, we have installed forced cooling in order to satisfy customer concerns.
We are concerned that this may result in a higher failure rate than Victron intends and we note that there is no warning between Venus OS and MPPTs about temperature. We have never observed an MPPT derating on over-temperature, which we would expect to see at temperatures over 40 degrees C per the datasheet entry above.
I'm sure places like Australia and the Southern US where Victron is also popular will also be experiencing the same sort of operating temperatures.
We have designed and are testing a robust, temperature driven forced cooling solution for our installations going forward but it comes at a cost and we need to determine whether this is actually necessary from Victron's perspective.
Any input or advice on this would be appreciated.