Valve has just reminded its users on Twitter that the Steam Deck is built for use in ambient temperatures between 0°C and 35°C. The announcement comes amidst the current heat wave in the US and Europe.
For our friends in the midst of a heatwave, a quick note about Steam Deck in high temperatures. Steam Deck performs at its best in ambient temperatures between 0° and 35° C. If the temperature gets higher than this, Steam Deck may start to throttle performance to protect itself.
— Steam Deck (@OnDeck) July 19, 2022
The company clarifies that the APU of the handheld gaming device runs well at up to 100°C. However, at 100°C it will start to throttle performance while at 105°C it will shut down. These are to protect the device, the chip, and yourself from damage.

If you’re looking to get the Steam Deck and are based in the Philippines, keep in mind this warning, especially with the typical weather we have here. It might be better to enjoy the device indoors or in an air-conditioned room.
Prior to the Valve reminder, Nintendo also announced a similar reminder on Twitter last week for Nintendo Switch users.