Sizing AC
tomgood46
| Posted in Mechanicals on
We are building a concrete ICF home in a constant hot climate … using ductless a/c … have been told by the ICF people that A/C may not be necessary … I’m not buying this … at least in bedrooms … what size a/c in the bedrooms … will 6000 btu work ? smaller/larger
Thank you
Tom Good
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Replies
Thomas,
Air conditioning is not necessary, of course, since people lived for millions of years without it.
If you want air conditioning, you need to perform a cooling load calculation (otherwise known as a Manual J calculation) to determine the size of your cooling system. Here is more information on performing cooling load calculations: Calculating Cooling Loads.
Your HVAC contractor is perhaps proposing that the entire cooling load of your house can be handled by just a few ductless minisplit units, without putting an indoor unit in each bedroom. This approach can work, although fewer hot-climate builders have endorsed it than cold-climate builders. For more information on this approach, see Just Two Minisplits Heat and Cool the Whole House.
You probably could get away with it, if you take advantage of prevailing winds and extend the overhangs to reduce solar heat gain. Or, an air exchanger would provide a healthy number of ACH.
Do you have humidity to deal with? If so, a dehumidifier would help give you comfort.