07-30-2018, 09:24 AM
I second what Thooks said. With the new filters made today, the criteria for return ducts need to be changed and/or enforced.
But some returns can't be changed- especially if the indoor unit sits in a closet in the hallway. New building codes should address this and the closets enlarged on new homes so a return duct can be run overhead.
For the last 30 years, I have always installed the 4" pleated media filters with all new systems. The filters get replaced once a year and I've had no problems with the indoor units getting dirty.
A filter may not look dirty since it is now picking up tiny particles that embed themselves in the pores of the filter. Change them once a month and you should be ok.
I can feel the weight in the 4" filters when they load up- they may gain 30% in weight.
But some returns can't be changed- especially if the indoor unit sits in a closet in the hallway. New building codes should address this and the closets enlarged on new homes so a return duct can be run overhead.
For the last 30 years, I have always installed the 4" pleated media filters with all new systems. The filters get replaced once a year and I've had no problems with the indoor units getting dirty.
A filter may not look dirty since it is now picking up tiny particles that embed themselves in the pores of the filter. Change them once a month and you should be ok.
I can feel the weight in the 4" filters when they load up- they may gain 30% in weight.