These figures are the Purge volumes....Not IV for soundness testing !!
E6 and U6 are well within scope. .02182 and .02742 M3 IV.
But there's a problem with the pressure drop to the appliance(s) and the installation needs attention and perhaps altering which would involve purging!
Without eyes on... I was suggesting to the OP (in my first post to this thread) that the installation might require a commercial ticket as it sounds borderline now and even more so when altered.