Solar Halo's Heatpump recipe hardcodes 2 petroleum gas barrels. Angel's Petrochem converts petroleum gas into methane and disables its barreling recipes, which leaves the barrel item in the recipe with no way to obtain it, making the Heatpump uncraftable. This swaps the dead ingredient for an equivalent bottled gas that is actually producible (methane by default). Runs in data-final-fixes and only changes anything if the original ingredient really is unobtainable.