My new a/c is really loud. The installer said higher grade filters would help. but it hasn't much. any ideas?

Question

new unit has air filters at air intakes, roars when the unit is running. Better grade filters have not helped much.

Answer 1

Was this a brand new installation or a replacement? If a replacement, did you increase the tonnage of the unit? Normally, the fan has to provide 400 cfm of air per ton in air conditioning. In order to provide a balance of good air flow and minimal noise, the ducting needs to be sized correctly for both the supply and return side of the unit. If your indoor unit is located in a closet, then the return air I assume is below the unit, so I'm guessing you hear the noise of the fan. You may be able to help yourself out somewhat by increasing the size of your return air, or adding an additional opening. Ultimately, the contractor probably will need to take air flow readings to see what type of static pressure is running in the ductwork. It sounds like you have more fan than the ducts can handle.

Answer 2

THE FILTER AND FILTER FRAME ARE TOO SMALL AND THE AIR IS RUSHING TOO FAST THROUGH THE FILTER AND CREATING THE NOISE.  FOR A SORT OF AN ANSWER CHECK THE WEBSITE I LISTED.   THE REAL ANSWER IS THAT THE MINIMUM SIZE IS MOST LIKELY DETERMINED BY THE MECHANICAL CODE FOR YOUR CITY OR COUNTY.  YOU SHOULD BE ABLE TO CALL INTO THE INSPECTION DEPT AND GET THE ANSWER IF YOU CAN GIVE THEM THE TONNAGE OF THE UNIT.  I WOULD ALWAYS GO WITH A LARGER FILTER THAN RECOMMENDED FOR SEVERAL REASONS.  IF YOU HAD AN UNLICENSED PERSON PUT IN A NEW SYSTEM, HE MAY NOT KNOW THAT HE INSTALLED AN UNDERSIZED FILTER GRILL.  JUST GET THE SIZE OF THE MINIMUM FILTER AREA REQUIRED AND HE WILL BE BACK AND FIX IT IF YOU LIVE IN A CODE AREA.  IF NOT A CODE AREA, YOU WILL HAVE TO NEGOTIATE WITH THE INSTALLER.