Originally Posted by alblancher
yea, I'd do it like the first drawing, a simple side box heat source with a perforated plate if he wants to diffuse the heat and get a bit of sizzle from the drippings. I don't know why you would need a water pan if the firebox intakes are adjusted properly and if you are burning wood. Dry wood still provides a good deal of moisture. Simple is better in my opinion.
I would only use a water pan in the vertical drawing #3.
Drawing #1 might or might not benefit from a water pan.
Reasoning for a water pan for #3:
The water pan helps maintain normal smoking temps because water boils at 212 and the 200+ degree steam fills the smoker and helps regulate the heat.
Water vapor will also increase the smoke penetration of meat (increased smoke ring), not sure of the scientific name here.
The water pan is also designed to catch the drippings from the meat, keeping them off of the fuel source.
Water in the pan acts as “thermal mass” and aids in heat recovery time.
Many will argue that it makes the meat moist I don’t buy into that.
Many also state that the drippings and other additives to the water pan help in flavoring the meat, this I am not sure of as well.
Others will use sand in the water pan for “thermal mass” but I feel by doing so the water pan is only acting as a heatsink.
If it was me and I designed a vertical smoker (drawing #3) it would definitely have a water pan, with that said and having used both types of smokers I would have to agree with you, my first choice would also be drawing #1 without the water pan, with the option to add later to help even out temps if needed.