While in creative mode, destroying the heat exchanger sometimes causes it to drop as an item. I have not seen this bug on any of the other blocks, just the exchanger.

Actually, it looks like the steam turbine does too. It appears to be from the fact that both of these blocks are bigger than 1 block. When one clicks to smash on the upper block part, that is what causes the item to drop in creative

Also, if you use pick block on the upper portion, it gives you a weird invisible slab block

it is a boundary block