With the Northern Hemisphere currently battling a nigh-unprecedented heat wave, Valve has a bit of a common sense warning for you: don’t try to play the Steam Deck if it’s too hot, inside or outside. The company took to Twitter to tell Steam Deck owners that the portable gaming machine works best at temperatures between 0° and 35° Celsius (32° and 95° Fahrenheit). Try and play it in an environment that’s any hotter, and it might start to throttle performance or shut down completely.

Specifically, Valve says the custom AMD RDNA2 APU will begin to throttle if it detects an internal temperature of 100° C (the point at which you could use it to boil an egg). At 105° it will shut down completely, in order to keep the thing from literally bursting into flames in your hands. 100° C is a pretty typical limit for computer components; plenty of full-sized PCs will shut down at that point, too. Valve is in good company here, too, as Nintendo sent a similar message to owners of the Switch last week.

All modern electronics have a heat limit — you might have seen your phone shut down if you try to use GPS navigation in your car on a hot day. The best way to keep the Steam Deck (or any modern PC) cool and happy is to run it in a well-ventilated area, out of direct sunlight, and make sure that the intake and exhaust ports for the internal cooling system aren’t blocked. On the Steam Deck that’s the top and bottom edge, plus the rear near where your right pinky sits.

If you’re lucky enough to have a working air conditioner, you and your Steam Deck should be fine. But if your home’s thermostat is inching towards that 35° mark, maybe read a book instead. I hear Snow Falling on Cedars is pretty good.