Hey Ed, Why Do I Have to Use the Indoor Design Condition 75 Degrees Fahrenheit at 50% Relative Humidity for Summer Cooling?
In this edition of "Hey Ed", Ed discusses why you have to use the indoor design condition 75 degrees fahrenheit at 50% relative humidity for summer cooling
Hey Ed, why do I have to use the indoor design condition 75 degrees Fahrenheit at 50 percent relative humidity for summer cooling? Those are the specific conditions that you’re gonna find in manual J, if you are following code compliancy, the codes will tell us that we’re supposed to select a piece of equipment using the guidance of manual S with the outputs that come from manual J. There are some very specific individual situations where a climate might require a higher relative humidity in the house and that will be specified by a local code but unless your local code specifies it, we’re supposed to follow that 75 degrees dry-bulb temperature at 50 percent relative humidity that is backed in manual J and that’s the way I see it.
In this edition of “Hey Ed”, Ed discusses why you have to use the indoor design condition 75 degrees fahrenheit at 50% relative humidity for summer cooling
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Ed Janowiak is the Manager of HVAC Design Education at ACCA.
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Posted In: Hey Ed, Residential, Technical Tips