I just had a new 5 ton 21 SEER Infinity system installed a few weeks ago and had a message on the Infinity Control saying to replace the filter!
I called my installer where he came out and did a static pressure test from the Controller where it read .82. He said this was too high....which from the reading I have absorbed, the optimal system should be around .5.
So the trouble shooting began:
I have an Infinity Air Purifier (GAPA) installed as well and when the filter is removed, the system drops to .42 - is it normal for this media filter to pull .4?
Reinstalled the filter and began removing the return register vents. After doing so, I was able to get a drop of .08 - down to .74.
I had all new ducts installed and supposedly resized correctly for the existing boots/vents. I don't recall any measurements were taken in each of the rooms, but rather based on what ducts were currently ran. For example, I had a 8" duct feeding two 7" ducts going to registers. The duct was resized to a 9" duct going to the 7's.
I would say every supply duct was increased anywhere from 1-3" and have about 8 ducts coming out of plenums. Would too many ducts cause static pressure issues or is this more of an issue on the return air side?
I have three return air ducts - 1 just under the furnace - 18", 2 about 30 - 40 ft away with 14" ducts
BTW - the blower is set at 1750 CFMs..