I use a windcover everytime i smoke. It makes my heat management easier, and heats the whole bowl so the glycerine at the bottom of the phunnel starts to vaporize in larger quantities.
i have two hookahs i normally use, a JandR 29" Syrian, and a Mya Acrylic 22" from H-S. I have been told smoke temperature is affected by many things, including hookah height (which i don't necessarily believe is true).
So used a windcover to smoke out of both of my hookahs. After about half an hour, i noticed the smoke in the Mya getting noticeably overly warm. I was moving the hookah over a couple inches, so i grabbed the Stem right under the tray and the base and lifted it. I had to pull my hand back in pain. The stem was VERY hot, much too hot to touch for over 2 seconds. I use 2-3/4 of an Exotica stick everytime i smoke, so there is a good amount of heat going.
SO i set up my Syrian, and started smoking out of that next. I used the windcover, smoked for about half an hour with 3/4 an Exotica like in my previous bowl, and then i tested the metal right below the Tray. It was cool. I kept smoking. I tested it again at about 45 minutes. Still cool. I kept smoking, tested it at about an hour and 20 minutes. Cool. The windcover had been on this whole time i had replaced the coals at about 50 minutes, but the phunnel was BLAZING hot.
This is just one more reason to buy a brass hookah.