Heat pump size recommendation
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it's not done by sq ft, do a load calculation - https://www.loadcalc.net/
2 ton may be too big on the cooling side and not dehumidify properly, but sizing a heatpump is a balancing act.
The heat strips are sized to handle the entire heating load. Load calculation would indicate - the choice will likely be between 10 and 15kw.
it really depends on the house - being single story, having ducts in an unconditioned space,east-west exposure, large windows, poor insulation can increase the required capacity.
2 ton may be too big on the cooling side and not dehumidify properly, but sizing a heatpump is a balancing act.
The heat strips are sized to handle the entire heating load. Load calculation would indicate - the choice will likely be between 10 and 15kw.
it really depends on the house - being single story, having ducts in an unconditioned space,east-west exposure, large windows, poor insulation can increase the required capacity.
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North Carolina can get pretty humid in the summer, depending on your location. An oversized heat pump (AC) will produce a cold, clammy environment. You don't want that, so be careful to get a proper cooling load assessment. I suspect a 1.5 ton would be closer.
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This is a pretty good site for sizing HVAC systems. I've always had good luck calling local HVAC supply vendor for help also.
https://hvacdirect.com/sizing-air-conditioner-and-heater.html
:glasses: :glasses: :glasses:
That’s a terrible choice for sizing. Nothing more then an uneducated guess.
No such sizing chart exists.
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I disagree the internet has many tools / sites to determine the correct size for your HVAC needs. Many have online or phone tech support to discuss the variables such as duct size, insulation, wall / floor building characteristics, how many floors, climate zones, etc.
Of course IMHO and YMMV
:glasses: :glasses: :glasses:
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Heat loss/gain is not proportional to sq ft.
A 1500 sq ft house can require as much or more heat in the same climate as a 3000 sq ft one. There are too many factors for sq ft to be used.
It's more proportional to exterior/exposed surface area than floor area, but still, insulation and leakage greatly impact heat loss/gain.
There's a lot of junk on the internet along with some good stuff.
A 1500 sq ft house can require as much or more heat in the same climate as a 3000 sq ft one. There are too many factors for sq ft to be used.
It's more proportional to exterior/exposed surface area than floor area, but still, insulation and leakage greatly impact heat loss/gain.
There's a lot of junk on the internet along with some good stuff.
Unfortunately that site you linked couldn’t be farther from the truth. It’s outright wrong.
Sizing isn’t about someone’s opinion. Nor is it one size fits all. And no charts or graphs exist to size your home.
You need a manual J to determine sizing.
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Those sites and THAT site aren't based on opinion, they're based on mechanical engineering principles of HVAC design.
Sizing residential HVAC systems not that complicated and IMO that site was perfectly fine for what the OP was asking.
Simple residential HVAC sizing isn't complicated as industrial manufacturing facilities with variable air volume vs constant air volume and humidity sensors in each room with DDC controls along with large chiller and industrial desiccant dehumidification systems with variable frequency drives and pre heating & cooling coils, that hold the system to a specific temperature and humidity design criteria for manufacturing purposes. Not to mention systems that are design around 100% outside air opposed to return air systems.
Again IMHO and obviously YMMV
:glasses: :glasses: :glasses:
Manual J is strictly for residential heat load calculation. Has nothing to do with industrial anything. In fact, commercial and industrial calculations have an entirely different formula.
Following the link you posted, if I had 2 identical 2500 square foot houses, located in zone 1, one with 2X4 construction with fiberglass insulation and the other spray foamed, what size equipment would I need?
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Again the site has online technical service to walk the user through the different variables as mentioned above.
:glasses: :glasses: :glasses:
Again, as has already been mentioned, equipment sizing IS NOT based on square footage.
Please study the art of proper equipment sizing before offering poor, incorrect advice.
www.loadcalc.net
http://efficientcomfort.net/assets/documents/Sizing_Selecting_for_Proper_Humidity_Control.pdf
http://efficientcomfort.net/assets/documents/Another_View_on_Equivalent_Sizing.pdf
http://efficientcomfort.net/assets/...t_Better-Sizing_Air_Conditioners_Properly.pdf
http://efficientcomfort.net/assets/documents/Understanding_HVAC_System_Design_Issues.pdf
Please study the art of proper equipment sizing before offering poor, incorrect advice.
www.loadcalc.net
http://efficientcomfort.net/assets/documents/Sizing_Selecting_for_Proper_Humidity_Control.pdf
http://efficientcomfort.net/assets/documents/Another_View_on_Equivalent_Sizing.pdf
http://efficientcomfort.net/assets/...t_Better-Sizing_Air_Conditioners_Properly.pdf
http://efficientcomfort.net/assets/documents/Understanding_HVAC_System_Design_Issues.pdf
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I never said equipment sizing was based on square footage. Please study the art of reading comprehension.
:glasses: :glasses: :glasses:
The entire link you posted is based on square footage. Including the big map that gives sizing ratings based on “zones”.
This kind of graph/map doesn’t exist for sizing. Links like you posted have people wind up with oversized equipment that performs poorly.
Sizing, unlike your opinion, is quite difficult and requires theory, science and mathematics to get right.
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In the theory of sizing it seems the known fact that -- moisture is removed first -- has been lost, then the air temperature changes.
Went through all of it. Even used the zip code quick calculator towards the bottom of the page. Said I need 6 tons of cooling and 120k BTU furnace for my home. Which is again, wrong.
You said-
But that site lists the information in the photos below.
The only thing that’s right about that site is all the way towards the bottom it gives a link to a manual J/manual D site.
But please, explain how a colorful map with sizing ranges per square foot is going to help someone size their equipment?
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You have to cool the air below dewpoint before moisture condenses - both happen but the ratio changes as humidity is removed.
decent sizing tools include the latent load.
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