How do stove BTU’s work and how do you calculate what stove setting (e.g. 1,2,3 etc) is how many BTU’s?

Question

I have a presto pressure cooker that isn’t supposed to be used on anything higher than 12,000 BTU’s.

I’d like to use it outside, but it says to not use on any outdoor heat source because higher BTU’s. Case in point, I have a Coleman classic double stove that kicks out a MAXIMUM of 20,000 BTU’s.

I could buy something like this (https://www.jbtools.com/sportsman-series-sbcishd-single-burner-cast-iron-stove/?wi=off), which says max 8,500 BTU’s, but if I can get by with my Coleman, I’d rather just do that.

But I’m wondering how i’d go about figuring out what heat setting on the Coleman is 12,000 BTU’s?

In: 3

Answer 1

Put a litre (ha, metric!) of water in a pan and heat it up at full blast (20 kBTUs) and time how long it takes to boil. Try and halve the power and check it takes twice as long to boil the water. You may need to do a little trial and error. Mark the half power point with a sharpee, that’s 10 kBTUs, bingo!