Would this be considered back drafting? The inner cover could not be installed properly because of damage to the bottom of the water heater
I would check for an ongoing back draft use a match and at least note evidence of past back drafting and recommend further evaluation and repairs as a health and safety concern.
Flame roll out like that is often caused by inadequate combustion air or a blocked exhaust flue pipe.
Without a internal cover in place I would simply say repair or replace.
It’s broke and needs fixing before the house burns down.
Larry and Mike are correct. The condition is referred to as “flame roll-out,” commonly caused by inadequate combustion-air, and if the unit is damaged, it should be repaired or replaced.
Flame Roll out will also cause carbon build up on the burners so they would have to be cleaned as well or you loose effeciency, and because the gas isn’t burned cleanly you may have a carbon monoxide situation. So as Michael and Jeff have already said it should be serviced or replaced which ever is cheaper and soon.