I have a Rheem Criterion Gas Furnace. At the moment, my air conditioning system currently has low air pressure coming from the vents around the house. I double checked that the fan is working, replaced air filter, and checked outside condenser and made sure it is working. There is no water leaking, no ice formations around the copper pipe either. Not sure what the issue is.
Should any air be escaping from RED (with square-dash) PVC cover pictured below? Right now there is a lot of air coming out of it and not sure if this is normal.