I own a 4200sq ft home in NJ. The home has a two-story family room in the middle, and a two-story open center hall. I have a two-zone HVAC system.
The home was built in 2005. It uses Goodman HVAC equipment. The two outside AC units are 3 ton and 4 ton. Since day one, the home has heated fine in the winter, but summer has been a nightmear.
Whenever it would get above 90 degrees outside, the upstairs of the home would have trouble getting down below 77 degrees inside upstairs. Downstairs would cool nicely, and the downstairs unit would cycle, but the upstairs unit would run forever. Even with both zones set to the same target temp of 74 degrees.
The home receives a lot of sun all day long, as there are no trees close by. The units were located at the rear NW corner of my home, facing direct sunlight all afternoon.
After the first year, I needed to have the two compressors (which are located next to each other) moved from one side of the NW corner to the other due to them being in the way of a major deck project. Simple task, since the line sets were in the basement, and only needed to be cut, pulled into the basement, shortened about 5 ft each, then fed thru the outside wall around the corner. I had an HVAC tech relocate the units and recharge the system.
One advantage of the move (I thought) was that the new location places the compressors just behind a fence that shades them from direct sunlight, so I was thinking that maybe getting them out of direct sunlight all day might improve overall operation and efficiency. Yes, no??
Since the move was done in the fall, I had the tech come back out in May the following season to charge them, and they seemed to work a little better than the previous season, but my upstairs zone never seemed to cool adequately as compared to my neighbors' similar sized homes.
Fast forward to May 2008, and now again I'm having difficulty. The other day it hit the upper 70s, and the upstairs unit would not cool down to below 77 degrees. Finally, when it hit the low 60s outside, I was able to get the upstairs down to 73 degrees or so.
My first thought is that either the system needs a charge again, or this system is just garbage.
Now, I think I may have discovered another alarming issue - I think the tech who performed the relocation/move may have reversed the upstairs and downstairs compressors. Right now, the downstairs system is tied to the 4-ton Goodman unit, and the upstairs system is tied to the 3-ton outdoor unit. Which zone should be using the larger compressor - upstairs or downstairs??
I'm an electrician, but my common sense leads me to think that since heat rises, the upstairs unit should be the larger unit, no? The other reason I think he goofed is that when the house was first built, the upstairs unit needed to be replaced when we moved in as it was defective from the factory, and that unit would be newer. The 4-ton unit's serial number is a year newer, and both numbers match close to the installation date timeframes, so that almost confirms my suspisions.
Another question - when he relocated the units, he removed the line dryer filters internal to the Goodman units and installed new ones outside of the compressor cabinets. Was this necessary when cutting and re-brazing the line sets?
Any thoughts on the subject?