4.5 tons = how many square feet? This house I just inspected has a 2 ton and a 2.5 ton heat pump for a 3 story 3100 square foot house. I am questioning whether the total tonage is enough for this spread out square footage. I thought a good rule of thumb was between 500 to 700 square feet per ton. Can any of you HVAC gurus help? Need a home inspection in Alabama? listing of Alabama certified home inspectors. Re: 4.5 tons = how many square feet? East TN Home Inspections LLC Knoxville, Oak Ridge, Maryville, Clinton, Farragut, Lenoir City, Pigeon Forge, Sevierville and all the surrounding areas. �The things that will destroy America are peace at any price, prosperity at any cost, safety first instead of duty first, the love of soft living, and the get-rich-quick theory of life.� Joe Funderburk, CBO, CMI Alpha & Omega Home Inspections, LLC Inspecting Upstate SC & Charlotte Metro, NC Angie's List Super Service Award Winner 2013, 2012, 2011, 2010.

I thought a good rule of thumb was between 500 to 700 square feet per ton. That "is" a rule of thumb, but it is not a "good one"! As Wayne was possibly trying to allude to, you cannot terminate tonnage by square footage. There are a whole lot of other factors that are more important.industrial ac window unit When you build the same type of house in the same weather zone you can "assume" that a certain tonnage will handle a certain amount of square footage.ac unit not cooling air If you have a two-story house with 50% less square footage on the second story than on the first, would you put a HVAC unit on the second floor 50% smaller than the first floor?ac power supply function The first floor has a buffer zone in the crawlspace or basement below.

It has a condition space above, so the major heating/cooling load is the perimeter walls. On the other hand the second floor as a buffer zone below (the conditioned first-floor). It also has the perimeter walls as a primary load (like the first floor). But the ceiling is against an attic that gets how hot? The roof above that attic is a solar collector and radiates, how much energy? There is thermal bridging issues with the roof framing and thermal bypass issues with the ceiling penetrations for electrical penetrations (thus significant air leakage). Hot air rises, so a significant amount of the first-floor cooling load may pass upwards into the second-floor zone and increased the load on that equipment… With this in mind, do you still feel that square footage per ton on the first floor is equivalent to the square footage per ton on the second floor? Originally Posted by rspermo I have questioned it many times the Manual J is only as good as the person using it

Originally Posted by gstrump These questions never have enough info......Makes a big difference, slab is better for cooling. Which floors did the 2.5 ton unit serve? The sizing for a heat pump in FL is all about the cooling but up here its all about the heating when on a slab foundation. I had to select my heatpumps for proper heating which ended up being a little large for the cooling calcs but they still run enough to remove the humidity. Main Line Inspections, Inc. National President / NACHI (2003-2004) NACHI Education Committee Member PA NACHI Certified Inspector # 01102902 Delaware Licensed Home Inspector # H4-071 ComPac® I & ComPac® II wall mount air conditioners The ComPac I and ComPac II air conditioners are the world's foremost wall mount air conditioners for cooling telecommunications shelters and enclosures. Because of the constant heat load, cooling is required throughout the year. Both the ComPac I and ComPac II air

conditioners have the necessary controls and safeties for operation in hot or cold weather. The primary difference in the two units is the factory installed economizer in the ComPacThe economizer cycle uses outside air, when cool and dry, to cool theThe economizer cycle can reduce run time on the compressor and the condenser fan motor by up to 75% thereby extending the compressor's and fan motor's life, reducing downtime and energy costs. Three model lines of ComPac wall mount air conditioners are built - the HVEA line, the AVPA line and the AVPC line. The HVEA line is our most efficient units with EER's (Energy Efficiency Ratio) up to 11.70 and feature an electronically commutated outdoor fan motor. The 3, 3.5, 4 & 5 ton HVEA models are available with a 2-stage compressor. cooling is approximately 65% of the total cooling capacity. The 2-stage compressor provides lower start-up amps which can be critical when operating with a generator. compressor also reduces energy costs and is able to more precisely match the cooling

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