Video: Don’t Rely on Old HVAC Sizing

So expert advice for your standard consumers when you're replacing your HVAC equipment, uh, what you really wanna look for is now equipment has changed dramatically in just the last 10 years. So when you're selecting an HVAC appliance, um, you need to look at a few different things. One, houses are not built the same way anymore.

So if you're looking at a 1970s house when you have maybe two inches of cellulose insulation in the attic and/or your duct work might be old, original hard pipe without insulation, um, these are a lot of factors that need to go into sizing your equipment. So when it comes to a, a, a professional coming out and saying like, "Hey, you got 1,200 square foot house.

We're gonna throw a three ton in here, and that should supply it sufficiently." We're way past that now. So now you really want to go into, like, your manual J calculations, which would be factoring in your ducts, your insulation, your windows, which way the sun's hitting your house. All of these factor in to sizing the equipment.

So when it comes down to it, a three ton to the 1970s house and a three ton to today's standard when you have your insulation levels up to R38 and you have radiant barrier in the attic, um, then all of your duct work could be Mylar exterior weather barrier with R8 value on the duct work. It's going to function extremely differently between one house and the other.

So biggest thing is to just factor in all of these things and make sure you have a professional that can go through every single piece of that house with you and make the correct decision.