What do you think the effective power generation and heat production is for whatever that reactor is producing, when not in a suit?
If memory serves correctly, the entire outer shell is a round metal cylinder, so that’s a fairly large surface area to transfer heat to the body. Tony might not need winter clothes if he’s got a portable heater in the chest.
Just got reminded of the silencer gun battle scene in one of the John Wick movies. That was perhaps the most unrealistic thing I’d seen in those.