New construction. The first picture shows a duct box with jumper ducts joined to it from the upstairs bedrooms. This assembly does not join to the air handler, it just goes open to a grill in the hall which is a few feet away from the actual return air grill.
The second picture shows the jumper duct grill next to the return air grill in the upstairs hall.
So it’s a good thing that we are not pressurizing rooms because air is being pushed through the jumper duct system.
The bad news is that this seems to be a big heat exchanger. The temperature at the jumper duct grill was 90 degrees F. The return air grill measured normal at 70 degrees F.
I don’t understand why they didn’t just join the bedroom jumper air ducts to the plenum and pipe the return air directly into the system.
Not the first time I have seen this but seems like a design flaw to me. On the other hand, I guess it shouldn’t make any difference. Perhaps just an easier way to accomplish the same thing.
What is your opinion of this type of configuration?