Is there any problem using a ball valve labeled for gas and not water on my mash tun? I could only find valves the right size that were labeled 'gas' and after putting it together it seems to work just fine.
it shouldn't be a problem. im assuming your talking about a brass ball valve. the only thing you need to keep in mind, is that brass has a small amount of surface lead. you can easily remove this by soaking the valve in a hydrogen peroxide/white vinegar solution for about ten minutes. if the solution starts to go green, dump it and pour some fresh stuff in.