[Q]Obviously, the ideal would be a load calc done but with already pursuing three bids and none of them even mentioning a load calc, I'm guessing the reality of finding someone that thorough is difficult, especially since with no AC currently, time of of the essence.
With 130 S.F. of glass (8 windows or less),
2-Ton is adequate for 1,140 S.F. residences
(<~10 years .. good windows, R-19 wall, R-30 ceiling) with basement in St. Louis.
Basement cooling load is likely <~20% of the total,
if there are no exposed basement walls or windows.
Air distribution may more of a concern than whether you wish to install a 2-ton or a larger 2-stage unit if Your thermostat set-point is < 75'F.
Is the cost difference for Variable Speed air handler
(> humidity control) important?
V.S. AHU also provides somewhat of a band-aid for an under-performing air distribution system.
I am sure many contractors would perform a load calc,
if one provided ~$1oo cash up front. Load analysis would take < half-hour for a 7-rooms residence if you provided all the details.
It's Not Rocket Science, But It is SCIENCE
with "Some Art". ___ ___ K EEP I T S IMPLE & S INCERE
Define the Building Envelope and Perform a Detailed Load Calc: It's ALL About Windows and Make-up Air Requirements. Know Your Equipment Capabilities
don't be hasty! I survived St Louis heat for 6y without a/c!
during this time, we had lots of sleet, which I now equate to high humidity --
oversized units will NOT control humidity in the house --
if you do your own calcs, then YOU will better understand where items are needing attention -- besides, you can measure, then add the dimensions of each room to be sure the totals match the overall dimensions of the house --
besides, your house may face west, with no shade; whereas the "standard" house may face north = MUCH differend needs, esp for a/c!
a properly sized system will save energy & last longer & provide comfort -- system = equip & ducts & filters
harvest rainwater,make SHADE,R75/50/30= roof/wall/floor, use HVAC mastic,caulk all wall seams!
A load calc was done and it seems our house is on the border between 2 and 2.5 ton. Given the age of the house (33 years but with newer windows) we decided to follow the recommendation of a 2.5 ton to replace our 2.5 ton unit and to add a variable speed blower to slow the air across the evap. coils and take out more humidity. It gets mighty hot here, we turn our stat up when we leave and have guests on a somewhat frequent basis, all of which seems to point to going with more cooling power when we are on the border. That and as a former Minnesotan, I tend to like it a degree or two cooler than the average Missouran.
We were able to downsize our furnace to 60000 BTU, however which netted us very little savings.
Thanks everyone for your comments