Updated version of Gas-fired furnace that fixes the issue with an updated version. This works with 1.1 not the other version which didn't get the necessary code changes. Curranty needs the bzgas mod to work as that mod has the necessary fuel_value added to the fluids.

https://mods.factorio.com/mod/gas-furnace

If any other mod could use let me know. It also does not currently work with the liquid smelting recipes with SE.