MPPT solar charger in weatherproof enclosure?

[rack04]

How bad of an idea is it to put a 20am MPPT solar charger in a weatherproof enclosure similar to this without any ventilation?

https://www.amazon.com/dp/B09NLW5HMX?psc=1&ref=ppx_yo2ov_dt_b_product_details

This would essentially allow me to have the MPPT solar charger exterior of a travel trailer that lives on my property.

 

[HRTKD]

I wouldn't put a solar charge controller in an enclosed box. They need air flow to manage their internal temperature. I have two Victron 100/50 MPPT solar charge controllers inside my RV trailer in a closet. I also have a fan in the compartment with a temperature sensor to ensure that air moves in/out of the compartment should the temperature get too high.

 

[Eoin]

Yeah as already suggested above about a sealed enclosure and restricted flow. The MPPT's have external heat sinks that require some form of air flow to dissipate the heat generated.
Additionally you're also creating another problem with humidity! As the MPPT heats during normal operation and with no form of insulation within the walls of the enclosure and the difference between the temp internally and externally will cause condensation on the internal surfaces of the enclosure.
And unless you have a waterproof MPPT, (which I'm guessing you don't, hence your query) this humidity could have a detrimental impact on the operating MPPT output!