AboutJim Barnhart Expertise Fifty + years in Heating, Ventilating, Air Conditioning, Sheet Metal Manufacturing.
Semi retired since 1995,
Experience Answer questions about , residential and commercial.
Answer questions about sheet metal fabrication.
Fifty years plus experience.
No answers for oil equipment, No answers for kitchen appliances, No answers for laundry appliances.
I have a split a/c system on a house that I just bought but do not have any manuals. There is a filter at the return panel in my foyer and one in the inside air handler which is in the basement. Our service person recommended only one to increase air flow but she seemed pretty young. Do I need both since that was how they were installed? If you recommend only one, which one would you use? I was thinking that if I don't have one in the foyer, the return ducts will get pretty dirty (based on how dirty the filter was when I replaced it).
Thanks,
Harold
Answer Harold,
If the two filters serve the same return duct don't use one in the foyer,
With a filter in the foyer that catches the dirt first it only makes sense that it would be dirty since it has the first chance at what goes in the return duct.
The dirt is not likely to stick onto your ducts inside but rather catch onto the filter at the unit.
Two filters in a return passage will cut down the air flow which in turn will reduce the efficiency and increase your electric bill.
A filter in a filter grill will reduce the air flow more then a filter at the return panel, You need to remove the filter at the foyer.
