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How are Design Conditions Determined?



CoolCalc uses design conditions specified in ACCA tables. It's important to note that heating and cooling design temperatures are not the most extreme temperatures that may occur in your area but rather the typical high/low temperatures that HVAC systems should be designed for in your area. ACCA design temperatures are updated approximately every 5 years.

Select the weather station that most accurately reflects the temperatures in your area. You may override the ACCA specified design temperatures only if local building code allows.

Useful Definitions:

Heating Design Temperature – In the winter, the temperature should remain above this value 99% of the time. 

Cooling Design Temperature – In the summer, the temperature should remain below this value 99% of the time. 

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    Peter Burry

    let people change their indoor design temperatures and add a warning. It is absolutely stupid to not let professionals change such a simple variable.
    Even if code specs something, someone may want their house warmer or cooler than basic code specs.
    Taking away this feature prevents people from using your calculator for custom jobs or experimenting with data.
    Just add a warning, that if you change indoor temps, it may not meet code requirements in your are. This is so simple
    And besides your now unchangeable data, seems to be causing people to fail inspections and approval, because you wont let them change the indoor specs to what they need.
    You already had it the program before, put it back please

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