# Will having two water pans in my smoker make any difference?

I have a backyard smoker, and I use a tray of water in it as thermal mass to help keep the temperature stable. I don't think the size of the tray is going to matter, but it's roughly 40cm x 30cm x 10cm. Having to keep the tray full of water is a bit of a chore, so I thought about putting a second tray of the same size in. Would this make any difference at all to the speed the water evaporated at? If not, what difference would a single larger tray make, if any?

One important thing to note is that my smoker is temperature controlled (like a normal oven), so it's going to stay at whatever temperature I set it to.

• Since you say the smoker is temperature controlled, I don't quite understand the problem. Is it that when you open the smoker the temperature drops significantly without the water tray in there? – pentane Oct 17 '18 at 11:59
• @pentane It's controlled by restricting airflow when the smoker hits the desired temperature, but it still goes over and dips under that temperature. Having a pan of water helps keep it more stable (and increases the humidity, which aids cooking). – Grim... Oct 17 '18 at 12:06

More water in the smoker = more stable temperature. You can prove this by putting in a smaller pan of water than usual and noticing that the temperature swings more.

Does adding more water change the speed the water evaporates at? The answer is kind of yes and kind of no. Here's a vapor pressure diagram:

If we lock the amount of water we are putting into the smoker, the graph can be drawn like this instead (y-axis changed):

So to answer your question: if you initially add more water to the smoker, yes you will get more water vapor after 60 minutes in the smoker. But the fraction of initial water you added will always been the same at 60 minutes no matter how much you started with. For example, after 60 minutes let's say half the water is gone. That will be true whether you add 100 grams or 1000 grams. That's why the answer is kind of yes and kind of no.

• Sure, but that's not the question I'm asking - I'm want to know how to provide more water. – Grim... Oct 17 '18 at 12:11
• @Grim... I thought you said you could put another pan in. That would add more water, no? – pentane Oct 17 '18 at 13:34
• Sure could. Would this make any difference at all to the speed the water evaporated at? – Grim... Oct 17 '18 at 14:28
• @Grim... I took a shot at an answer to the question as best as I understand it. If there's something I could improve on, let me know :) – pentane Oct 17 '18 at 15:34
• No, that's cool. So basically the more water I can get into it, the less often I'll have to fill it up. Thanks! – Grim... Oct 17 '18 at 16:29