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Thread: cfm's in a ton

  1. #1
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    cfm's in a ton

    How many cfm's in a 1-ton unit, a 15-ton unit and a 20-ton unit?

  2. #2
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    Nominal CFM would be 400 per ton. This will vary on the application.
    Go Rangers!

  3. #3
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    and I think about 450cfm for heat pumps, if you're talking BTU cooling 12,000 BTUH is one ton of cooling.

  4. #4
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    Quote Originally Posted by lwarren View Post
    Nominal CFM would be 400 per ton. This will vary on the application.
    unless of course were talking liebert my boy....

  5. #5
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    Quote Originally Posted by jern View Post
    and I think about 450cfm for heat pumps, if you're talking BTU cooling 12,000 BTUH is one ton of cooling.
    That would be 350 for heat pumps.
    " Kill a Commie for Mommy! "

    - Colonel David Hackworth (1930-2005), Korean War Vet

  6. #6
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    Quote Originally Posted by coolwhip View Post
    That would be 350 for heat pumps.
    I allways shoot for 400 a ton but I learned that you got to have a minimum of 300 and a max of 400 a ton.
    "I could have ended the war in a month. I could have made North Vietnam look like a mud puddle."
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  7. #7
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    Never put in a HP, maybe Im thinking of the heat side being cooler so you dont want quite as much cfm...Im tired.
    " Kill a Commie for Mommy! "

    - Colonel David Hackworth (1930-2005), Korean War Vet

  8. #8
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    400 cfm per ton is just a rule of thumb. You should check each manufacturer for specific info.
    Anything worth doing, is worth doing right......the first time!!!

  9. #9
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    Quote Originally Posted by stltechfrmtx View Post
    400 cfm per ton is just a rule of thumb.
    "Ton" refers to a BTU rating not really CFM. 12,000 = Ton

  10. #10
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    Quote Originally Posted by RLJ79 View Post
    "Ton" refers to a BTU rating not really CFM. 12,000 = Ton
    But when most reference cfms in terms of a unit, the "rule of thumb" is for every 12000 btus there should be 400 cfm.

    its just easier to say cfm per ton
    Anything worth doing, is worth doing right......the first time!!!

  11. #11
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    # Heat pumps and air conditioners are generally sized in tons. Typical sizes for single family residences are between two and five tons. Each ton equals 12,000 Btuh. It is important to note that actual capacity is not constant and will change based on outdoor or indoor temperatures. The published capacity rating of air conditioners and heat pumps is based on performance at the ARI standard temperature levels of 95 F outside, 80 F inside.
    www.hannabery.com/hvacwords_2.shtml

    # unit of refrigeration - equal to 12,000 Btu's/hour
    www.aaronprocess.com/glossary.asp

    # A unit of measurement for cooling capacity. One ton = 12,000 BTU's per hour
    www.helmsheating.com/HVAC%20GLOSSARY.htm

    definitions from Internets.

  12. #12
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    Quote Originally Posted by lwarren View Post
    Nominal CFM would be 400 per ton. This will vary on the application.
    I have some 60 ton watersource heatpumps running 170 cfm per ton. Of course they are 100% OA units and they don't work worth a crap.
    Go Rangers!

  13. #13
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    actually fellas you should design your cfm per ton around the calculated load design... example... if i had a home with alot of living biological plants ie trees open water etc.. one would design for higer for latent.. if i had alot of glass but very little lantent loads i would design for higher ensible loads etc. etc. etc. you just need to know what your cooling before you can say cfm per ton. ive had loads come in at 550 per ton and ive had some at 350 per ton.. same tonnage just different cfm per ton.. so the lesson is design first then cfm to accomadate..

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