I need some guidance on what to do with existing HVAC. I don't know if I should get the existing duct system sized correctly to support my current system or put in properly sized equipment. Some background.. I have run the HVAC-CALC load calculation program for my house and from my results the equipment is way over (especially heat) sized. Results were:
sensible gain - 22,116
latent gain - 3109
heat loss - 34,737
My existing system is the following (all Amana installed in '97):
GDC090x40b (87K BTUH output)
RCC36 (3 Ton 12 SEER)
CHH36TCD (horiz coil)
From my previous post and member responses, I belive my duct work is minimum at best for supporting my 3 ton. Note: my original system was a 2.5 ton heat pump. Currently in heat mode, the fan speed is set to medium and from looking at the Amana spec sheet (assuming 0.5 ESP) thats around 1657 CFMs. There is a lower speed setting that could be used that keeps the temperature rise in spec and that would be around 1386 CFMs (medium-low). The low speed which is where my AC runs doesn't look like that would be safe because of the temperature rise would be close to maximum.
1. Should I take out the existing equipment and downsize or upgrade the duct work to support existing equipment?
2. How can I check and verify the temperature rise to ensure its within spec?
Comment: this is a great site and I wish I had known about it back in 1997 when my system was replace. No the contractor didn't do any load calculation or Manual D and that why I'm trying to learn as much as I can now.
I do have one other question and this has to do with the HVAC-CALC program. Why doesn't this program add any latent gain for duct loss? When I use the Excel MJ8 spreadsheet that comes with the book, it added about 620.