What capacity of brewhouse are more suitable for direct-fire heating?

When choosing a heating source for your kettle or hot liquor tank, there are many factors to consider.
The size your system, space avaiable, heating time, of course, money will be a few of the factors.
Electric, Steam, Direct-fire as the three most popular heating type.

In my opinon, Under 500L equipment usually heated by electricity.
electric with a higher requirements for power supply. And if with high capacity, it is going to heat up slowly.

More than 1500L equipment usually with steam heating, steam can heat evenly and the temperature can be controlled easily.
Steam heating is the most recommended way of heating.

For the 600L- 1500L brewhouse, steam heating and direct-fire heating are all available. 
Should you prefer the direct-fire heating, we suddenly thought of a point.
 
When you install the chimney, we suggest adding a plate (adjustable),  it can control heat loss well. As following picture.
And from the picture, we can found there is guide plate, this design makes the heating more unifom.
 
Main structure of Direct fire heating just for your reference.

 
Which heating type you prefer, hope we can have a better discussion.
 
Edited by Cody
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