There is all kinds of information out there about HVAC system sizing. None of them replace having a proper heat load calculation performed. You should have a professional calculate the exact size you need.
A big percentage of heating and air conditioning systems are installed when the house is built sized wrong from the start. So even replacing the system with a new one may warrant having a proper heat load calculation done.
For more information on Griffin Air, visit https://www.griffinair.net/
For more information on New HVAC Guide, visit https://www.newhvacguide.com/

Hey guys before we get to the video for more tips and tricks in the heating and air industry, please click that subscribe button, hey guys, joshua griffin, air serving the middle peninsula and the northern neck, and i wanted to do a video that i think will help Some of you, if you come across this video when sizing a system for your home - and that is because, in my opinion, and a lot of guys that do what i do they'll tell you, there's some misinformation on the internet. People telling you how to size something for your home, how big your system should be, and i wanted to do just a real, quick video touching on that, because i think it's important for you to understand as the homeowner that there's more than just square footage. That's taken into account when we are sizing heating and air systems in homes. So it's not just a a matter of you know it's this many square feet and you're in this part of the country.

So your system is going to be this big. There's lots of other things that we take into account and in fact i would recommend in a lot of cases, whether you're, replacing a system or installing a system for the first time, and that is having a proper heat load. Calculation done in your home. Even if you have to pay for it, i think it's worth it.

Let's say you're building a house and for the first time a system is going to be installed. I can't tell you how many and i'm i'm telling you from experience. I know there's other heating and air guys that will agree with this, and that is, i would say, the majority. The majority of systems installed in homes today are not sized properly they're, either too big, too small, whatever in my market they're, usually too big, and that can create other issues such as moisture issues and humidity and comfort in your home.

What we see here and i'm sure a lot of parts of the country builders are trying to get by with the lowest dollar they're going with. Whoever is willing to install a system, for you know the least amount, and because of that things like a proper heat load, calculation are not done now, i'm not saying there's any problem with going with someone that is charging less than someone else. You know, i think in some cases you get what you pay for, but i think in some cases you know you should watch your money right. Well, i just want to let you know on having that proper helo calculation, just because you're going with someone that does only new construction.

They just install these systems and they're on to the next one, no problem with that. There's guys that that's what they do and they do it well. However, those guys are not always doing everything necessarily properly, so i would recommend having a proper heat load calculation done. We have companies locally, that that's all they do.

They don't install anything, they don't repair. Anything all they do is proper heat load calculations for companies and homeowners to make sure it's done right so find somebody that does that, if you don't know of anyone in your area, that does that call some of the local supply houses say hey. I need a proper heat load calculation done in my house, i don't mind paying for it. Do you have somebody that'll do it properly and what i mean by properly is they're going to take into account more than just the square footage they're going to take into account cubic feet of the home, meaning ceiling heights, and things like how many windows, the home Has how many appliances are in the kitchen that matters believe it or not, and so on insulation i could go on and on on things that they take into account when they're doing a proper heat load calculation.
So i just wanted to touch on that. I know. There's websites and i've seen these charts where it has like a region of the country and it'll say if you're this many square feet in this. You know region this.

You should have a three ton system. I just want you to know that that is not a proper heat load calculation. I'm not saying that it won't be accurate. It very well could be accurate, but how would you know so? I hope that helps thanks for watching.

The last thing i'll say is if you're in the market for a new heating and air system and you're in virginia and the middle peninsula or the northern neck, give griffin air a call. We'll give you a free estimate and the best warranty in the area. But if you're, not in our coverage area check out my new website, i've even got a little banner up here. New hvac guide, dot com check out that site because we've put so much information on there.

It's as if i wrote a book telling folks, hey here's. The good and the bad avoid this or that i've even got a whole page called no knows things to stay away from, and so before you spend thousands check out that website and finally for more tips and tricks and the heating and air industry click that subscribe Button thanks for watching.

6 thoughts on “Wrong! misinformation on the internet about hvac system sizing and what you should do instead.”
  1. Avataaar/Circle Created with python_avatars Guy Service says:

    Is there a map for Canada I may be able to see?

  2. Avataaar/Circle Created with python_avatars B391 G328 says:

    Trying to get a new gas high efficiency furnace here in Massachusetts. My old one is a 96000 btu furnace with pvc flue. 2500 sq ft house , does have 2 zones temptrol, built in 1995. Why am I getting some companies say I need 80,000 BYU’s and some say 100,000.? Old one seems ok.

  3. Avataaar/Circle Created with python_avatars Federico Pivetta says:

    Thanks for this incredible explanation and I think I went with the wrong size during a recent change out this past April. We live in the piedmont triad of NC and had a 30 year old Carrier system which consisted of a 3 ton 10 seer A/C, installed in 1991 and a 114,000 BTU furnace (1988). Finally this past March the A/C failed completely and we decided to do a change out. I had 3 companies do a load calculation and they all came back with 60-80,000 BTU Furnace and a 2 ton A/C which at the time I thought it would be too low. Some other folks just wanted to replace everything with the same size and we decided to go with a 90,000 Two stage Lennox Furnace and a 2 1/2 Ton A/C Elite. Still smaller than what we had before. Our installer did a beautiful job and used a 4 ton coil in order to get a proper AHRI match. The system is very well built and super quiet. I am fairly mechanically oriented and can tell that the components and built quality are excellent. However we are having issues with humidity and it is hard to keep it under 52%. I keep turning the thermostat down and it feels cold but we noticed that the system short cycles a bit. on a different situation last week we had an incredible hot day and the furnace in the evening ran non stop for about 2 1/2 hours and the humidity barely came down to 49%. Our old system kept humidity in the Summer months between 42-46%. As I understand ideal humidity should be between 35-45%. Our installer decided to slow the fan speed down in order to create a longer cycle and that way would remove more humidity and may reduce it even further. I am guessing that I miscalculated the size and was comparing BT'Us from a 33 year old system to a more modern one. We will see how the furnace does this winter. We got a terrific price with top of the line equipment and some rebates from our local utilities. Just concerned that it won't last very long and the energy savings will not be all that great., not to mention comfort and the possibility of having mold issues in the future. We also had our 75 year old ducts cleaned and what came out was unbelievable. We have noticed a great reduction in dust and are using a 4 inch media filter. Thanks and comments/suggestions are welcome. Forgot to mention that our house is 1550 square feet with 8 foot ceilings.

  4. Avataaar/Circle Created with python_avatars Bob Y says:

    Fortunately here in the St Louis metropolitan area, St Louis County provide a worksheet ( one of the best I've ever worked with). From a normal size house plans, say 2500 square feet it takes about a half an hour or so to complete.The big Builders still get around it a little bit by using the same worksheet for each house model they may have, even though the house may face a different direction ( it's close but we still find some under size systems ). We are also required to put a cold air returns in every room but the bathrooms or kitchens . The St Louis County worksheet is so good, all the surrounding counties and the City of St Louis honor it. I just wish code enforcement would require two systems for all two story houses but they still let the builders get by with one large unit.

  5. Avataaar/Circle Created with python_avatars chrisbabolat says:

    Manual D for proper duct sizing Are you in Orleans ?

  6. Avataaar/Circle Created with python_avatars chrisbabolat says:

    Manual J

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