I was perusing the Primus web site the other day. Like a number of other contributors to this site, I have a Trangia Stormcooker with a Primus gas conversion (together with a tragic collections of Snow Peak, Optimus, MSR stoves) and have often wondered about the heat rating (W/BTU per hour) of the Primus gas burner. I think that I have found it. It looks very much like the Primus EasyFuel. Same burner head, same pre-heating tube and same fuel line and control. If it is, then the rated output of the Primus gas conversion is probably very similar to the Primus EasyFuel and that's 3000W / 10,500 BTU per hour.
If you have a Primus gas conversion, you can check for yourself.
http://www.primus.eu/Templates/Pages/3_ ... ionId=5888 and click on Stoves
rucksack