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Posted By: rknikko 12 tons HVAC = how many HP? - 04/26/05 02:48 AM
Do anyone how many HP if there is a 12 tons HVAC? How do we calculate this?

Thanks.
Posted By: NJwirenut Re: 12 tons HVAC = how many HP? - 04/26/05 10:21 PM
According to:
http://www.onlineconversion.com

,12 ton of refrigeration = 56.5713594 horsepower [electric]

The conversion factor is 1 ton = 4.714 HP

However, if you are sizing feeders, etc., you need to go by the nameplate data on the motors, or other manufacturer's data.

[This message has been edited by NJwirenut (edited 04-26-2005).]
Posted By: northstar Re: 12 tons HVAC = how many HP? - 04/30/05 12:54 AM
Thanks for that site NJ.
Posted By: NJwirenut Re: 12 tons HVAC = how many HP? - 04/30/05 01:18 AM
I keep that one right at the top of my bookmark list. One of the handiest sites on the 'net...
Posted By: ironman Re: 12 tons HVAC = how many HP? - 05/03/05 04:13 AM
NJ is correct that you must use the ampacity and fuse ratings on the unit's data plate to size the feeder. However, the info from the online conversion table may be misleading in regard to your question. In practical A/C application, 1 ton = 12,000btu = 1h.p. compessor motor. Therefore, a 12 ton A/C would have a 12 h.p.(approx.)compessor or two 6 h.p.compressors.

The term "ton" comes from an early measurement of a system's capacity to reject heat. A one "ton" system would reject enough heat to melt a "ton" of ice in 24 hours.


Bob
Posted By: Alan Belson Re: 12 tons HVAC = how many HP? - 05/03/05 10:26 AM
http://www.eng-tips.com/viewthread.cfm?qid=987528&page=5
This may help.
Alan
Posted By: Alan Belson Re: 12 tons HVAC = how many HP? - 05/03/05 10:38 AM
typo! should be-
http://www.eng-tips.com/viewthread.cfm?qid=98752&page=5

Alan
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