How To Determine House Square Footage HVAC

Hey, I’ve had the same propane furnace since 1993 and am on my second HP. Yes, I am ignorant at this point. I’m trying to gain enough knowledge to be somewhat aware of recognizing truth when I speak with a couple of HVAC companies. We only have 2 “reputable” ones here. Over 30 years in business.
Hopefully they are better than the reputable mechanics that you use.
 
Assuming you don't want to spend a lot of money and have wall units in your house, just ignore that recommendation. You already have duct work, it would make sense to use it for the new system.


LOL

The better mini-split companies have INDOOR AIR HANDLERS that LOOK, FEEL and ACT just like what you have inside now, connected to your ductwork. They also connect to your existing ductwork, just like a replacement air handler would from Trane, Lennox, Bryant, Carrier, Goodman, etc.
 
LOL

The better mini-split companies have INDOOR AIR HANDLERS that LOOK, FEEL and ACT just like what you have inside now, connected to your ductwork. They also connect to your existing ductwork, just like a replacement air handler would from Trane, Lennox, Bryant, Carrier, Goodman, etc.

Oh? I didn't gather that you were suggesting the the OP rip out his propane furnace and replace it with an air handler...

Air handlers. Not furnaces. Sure, you can install heat strip coils in them. You'll just need an electrician to install the wiring for that, and perhaps (almost certainly) an electrical service upgrade.

Running a heatpump without any backup source of heat isn't my idea of a good idea. Especially in a place where it can get below 10F overnight sometimes, as does happen where I live in Virginia.
 
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First of all, I know how to measure and multiply and add.

I’m considering a new HVAC system and am trying to do a little research on my own.

My main floor living area is 2000 ft 2. Downstairs is 90% underground and a finished 1500 ft2. When my system was installed 30 years ago, my basement was unfinished.

Do I just add them together or do I discount my underground living area?

My old Lennox Pulse from 1993 still running strong.
I've got a couple of 93 era Carrier units that still run like tops, NG heat and R22 AC. Presently building the retirement home, in a different county but still in VA, and going through this process myself on new construction. Trane seems to be the choice around there and the prices are kinda nuts (to me anyway), for dual 15/17/20 seer heat pumps with propane aux heat downstairs and electric aux upstairs...like 55-64K depending on seer selected, its 3680 sqft.
 
I’m considering a new HVAC system and am trying to do a little research on my own.



My old Lennox Pulse from 1993 still running strong.
New HVAC systems, or those sold the last 10-20 years, are all pretty much junk, with major components made in China, even if the units are assembled in the USA. The unit I had installed in my Florida place in 2014 had a bad compressor a little after one year. Yes warranty cover the part but labor and freon was $400. And just recently, $1000 to leak test the system for a rusty evaporator.

If your older system is good, keep it. If it breaks, repair it. Have a 1990 Amana at home and wouldn't change it unless absolutely had to.
 
If what you already have is working then stay around that size for the new unit.

Ive seen to many times where guys will go in and up size equipment because of airflow issues in a house. 2nd floor not getting enough cooling for example. Bigger equipment will not fix a lack of airflow or under sized ducts. This is also bad for the new equipment because its lacking proper airflow.
 
If what you already have is working then stay around that size for the new unit.

Ive seen to many times where guys will go in and up size equipment because of airflow issues in a house. 2nd floor not getting enough cooling for example. Bigger equipment will not fix a lack of airflow or under sized ducts. This is also bad for the new equipment because it’s lacking proper airflow.
This. My first house was grossly oversized (80k btu furnace for 1200sq ft!) and short cycled like crazy. Whoever did my current house nailed it perfectly, it’s pretty much always comfortable on all but the hottest of days, but I *think* I fixed that problem by tinting the giant bay window that faces east.
 
Also.... Be prepared for sticker shock. A residential system change out today with decent equipment (not Daikin, Mitsubishi) is running $3500-5000/ton for equipment, new refrigerant piping and MINOR ductwork modification. There's some new efficiency regulations in effect for 2023, with new refrigerant regulations coming in 2024 or 2025. The manufacturers are in a tizzy....they have some major expenses renovating lines for all this and they pass that expense on to who buys the equipment.

This. This week I paid over $8000 for a new gas furnace, AC split system and minor ductwork modifications to replace problematic 20+ year old equipment. It’s a 2 ton system for a 1,500 sqft home. Sticker shock for sure. The HVAC company said prices on all equipment were going up 5.5% March 15 from their suppliers and in 2025 when new regulations come out they expect prices to go up at least 30%.
 
Manual J is the way to go. In the basement there's not much if any heat load for AC. Dehumidifier is more important in the basement. Remember that the installation/ installer is the most important thing. You can buy the best equipment have a bad installation and your going to be miserable.
 
Don't forget to check your local energy providers. May have some useful rebates to offset some of the costs, depending on the approved energy efficiency of the new equipment. Well worth exploring.
 
First of all, I know how to measure and multiply and add.

I’m considering a new HVAC system and am trying to do a little research on my own.

My main floor living area is 2000 ft 2. Downstairs is 90% underground and a finished 1500 ft2. When my system was installed 30 years ago, my basement was unfinished.

Do I just add them together or do I discount my underground living area?

My old Lennox Pulse from 1993 still running strong.
Im trying to understand your post. Are you planning something different for your house compared to the system that you have?
If you were happy with the current system for the last 3 decades why not replace it with another basic uncomplicated unit of the same rating and go on enjoying life?
The new basic unit, more energy efficient, will lower your bills and the replacement cost will also be the lowest. Dont fall for sales gimmicks and complicated installation. Do a direct replacement and you will be good to go trouble free unit which I assume will carry you through your retirement years. :)

Not in all cases but be weary of "rebates" typically when government money is involved, you're paying full retail price for the system and its the installer making the money from that rebate. Not you suing money. Meaning rebates are an easy sell for installers and they can work on a higher markup as the homeowner thinks they are getting the deal. The Solar Industry is much the same and EV makers too.
 
This. This week I paid over $8000 for a new gas furnace, AC split system and minor ductwork modifications to replace problematic 20+ year old equipment. It’s a 2 ton system for a 1,500 sqft home. Sticker shock for sure. The HVAC company said prices on all equipment were going up 5.5% March 15 from their suppliers and in 2025 when new regulations come out they expect prices to go up at least 30%.
Interesting, my son just had his 25 year old unit replaced by a local guy he likes. I think he paid roughly 7k for a basic Heatpump and handler, seemed expensive to me, must be around the same size home as yours. American Standard Silver series, basic one stage, I told him go basic, not that he listens to my advice all the time *LOL* but he agreed.
Anyway that is here in SC and his local guy who lives near him too, told him the same thing. He had it done in Jan and was told the price he got was the old price and they are going up in another month or so.
Anyway, just confirming what you were told about the price increase.
 
This. This week I paid over $8000 for a new gas furnace, AC split system and minor ductwork modifications to replace problematic 20+ year old equipment. It’s a 2 ton system for a 1,500 sqft home. Sticker shock for sure. The HVAC company said prices on all equipment were going up 5.5% March 15 from their suppliers and in 2025 when new regulations come out they expect prices to go up at least 30%.
Couldn't be. I have no idea what I'm talking about. Better listen to redddddits


Yes, I heard this morning that most residential equipment, across the board, across all manufacturers will see a 30-50% increase in cost in the next 12-18 months.
 
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