Cooling Load Check Figures Ashrae Pdf -

Let’s look at how to use the cooling load check figures to validate your model in under 10 minutes.

The 400 sq ft/ton Rule is Dead: How to Use ASHRAE Fundamentals to Sanity Check Your Cooling Loads

Let’s say you modeled a 2,000 m² (21,500 ft²) mid-rise office building (perimeter zones). Your software says total cooling load = 280 kW . cooling load check figures ashrae pdf

Also, They are ±20% accurate at best. They are a filter , not a scale .

Stop using 400 ft²/ton (which equals ~85 W/m²). That ignores windows, people, and latitude. Let’s look at how to use the cooling

But does that feel right?

Blindly trusting the output is dangerous. Before you size a chiller or select an AHU, you need a rapid, engineering-based sanity check. While many engineers still whisper the old rule of thumb (400 sq. ft. per ton), ASHRAE Handbook—Fundamentals provides a much more accurate, albeit often overlooked, method for spot-checking results. Also, They are ±20% accurate at best

Open your ASHRAE Handbook—Fundamentals. In the current edition (2021/2025), Chapter 18 (Nonresidential Cooling and Heating Load) contains the gold mine: Table 9 & 10 , typically titled “Cooling Load Check Figures for Typical Commercial Buildings.”