I didn’t read all of the posters explaining what was what in the remaining industrial parts of the Evergreen Brickworks. But it seems that many ovens were needed along the side of a long tunnel (behind the ovens) containing the bricks to ensure they all baked properly. And each seems to have been fed by one or more gas lines.
This last photo was near what seemed to be a play area: covered, but exposed on one side to the elements. Not an oven, but near them.