Inlet Plenums for AHUs

[HVACHawaii]

Anyone have any opinion on inlet plenums boxes? Are side connections to inlet plenums directly before filter boxes okay? I have a condition where we were not able to fit the ductwork otherwise, just wondering if anyone thinks this may be problematic. Any help is appreciated.

 

[imok2]

You may be short of air because you could have a condition known as stacking causing turbulance. Remember air flow in ducts resist changes in flow

 

[BronYrAur]

You may also see uneven loading of the filters, which isn't a huge deal. Some may need changing before others.

If you're in Hawaii as your name suggests, you should have no concerns of freezing. if you are in a cold climate, the freeze stat may see well-mixed "warm" air while another part of the coil is seeing freezing air.

Otherwise, as long as you can get enough air, you may only be paying a penalty of a little more energy consumption.