PennSilverTaco's HVAC BS MegaThread!

Oh yes it gets hot; From the beginning of June through the middle of September it is generally above 80 degrees. Temperatures close to and often above 90 are very common!

My house is like 3,000 square feet and has two units; 2.5-ton for 1st floor/basement and 2-ton for 2nd floor...

 

In Pennsylvania, at least in my area (Southeast/Philly suburbs), your exact house would have a 4-ton or 5-ton; In most areas of the Northeast/Mid-Atlantic, you could get away with a single unit in a 1-story of that size...

 

Do you have a basement? What brand is your air-conditioner?

 

Answering the OP's original question and for all HVAC nerds out there, there is a free software tool by the Dept. of Energy called RESCheck https://www.energycodes.gov/rescheck It's used to check if your house complies with the energy code of your jurisdiction. You can input the total roof, exterior wall, insulation R value, windows, etc. areas of your house and calculate the total heat loss. Insulation is obviously important, because a large but well-insulated house can get away with much less energy use compared to a small but poorly insulated one.

 

Thanks!

In my area, the code for new construction homes calls for two separate units if the house is larger than 3,300 square feet, or something like that...

 

What brand is your HVAC system?

 

Goodman? That's what my house has...

 

These relatively small York units are were a mainstay in tract Home subdivisions form the late 1980s all the way through the early 2000s (I found the pictures online; Not mine); There are several homes around the corner from my own that still have them in service, rusted and sometimes sinking into the ground, but still operational! I'd say the houses in question are anywhere from 1,900 to 2,600 square feet, so not as big as mine, but I can tell you from experience and my own research that any 2-story house over about 1,500 square feet would benefit from either two separate systems or at least a zoned system with dampers and multiple thermostats!

 

Not one of my favorite brands, but they've gotten a lot better just in the last 5 to 8 years? Did yours come with the house?

 

Don't be fooled by the odd design or the fact that production ceased almost 40 years ago; The York Champion "Tombstone" is one of the best air-conditioners ever made!

 

in AZ I run an 18 seer 4T 2SC at 1800 SF and at times it cant really keep up, (120 Deg) slump block house w/ 2payne windows heats ok in the winter on a natural gas.

 

Mini-splits.

SEER rating of above 20, preferably 25.

Do you oversize 10-15% of the BTU calculation needed, so you can have capacity since it can be turndown all the way to 25% condensing load?

I have a two story block construction building that is 90 years old that is 400sq ft per floor. My calculations tell me it needs 18,000btu cooling for both floors because we live in Florida and the building is below average insulation. I think I’m looking at 18k, and 24k dual head units.

Any and all advice is welcome.