wearing a firesuit should prevent you from getting hotter

[Zafhset]

Firesuits protect well enough against atmospheric temperature as is, and this works well enough when operating anywhere near a heat source. If the air is hot enough to scorch you in your firesuit, you probably shouldn't be standing around there at that point.

It doesn't even protect you against normal fires very well, since your body heat rises anyways and you start taking damage very quickly.

I don't actually think you should try firewalking just because it's called a firesuit.