{"id":19241,"date":"2023-12-27T17:32:51","date_gmt":"2023-12-27T09:32:51","guid":{"rendered":"https:\/\/aircondlounge.com\/?p=19241"},"modified":"2024-03-26T12:03:47","modified_gmt":"2024-03-26T04:03:47","slug":"how-to-size-ahu-cooling-coil","status":"publish","type":"post","link":"https:\/\/aircondlounge.com\/how-to-size-ahu-cooling-coil\/","title":{"rendered":"How to Size AHU Cooling Coil? (Design Calculation)"},"content":{"rendered":"\n
Sizing the cooling coil of an AHU is one of the essential HVAC design calculations. The calculated cooling load does not equal to the capacity of the AHU cooling coil. So, how do you size an AHU cooling coil?<\/p>\n\n\n\n
To size an AHU cooling coil, first, determine the required airflow. Then, identify the on coil and off coil temperature of the cooling coil and use the psychrometric chart to find the enthalpy difference. Finally, multiply 4.5 by the airflow and the enthalpy difference to get the AHU cooling coil size.<\/strong><\/p>\n\n\n\n Many engineers thought that the cooling load calculation result is the AHU cooling coil size. But, that’s not true. We need to account for the outdoor air as well as the heat gain in the duct.<\/p>\n\n\n\n AHU cooling coils can be sized using software or manually using the psychrometric chart. We estimate the cooling coil size for various preliminary design purposes. During construction, suppliers will use their software to determine the actual cooling coil size.<\/p>\n\n\n\n Below is an example of how to use the psychrometric chart to size an AHU cooling coil. There are a few things we need to obtain but basically, we want to identify the enthalpy of the air before and after the cooling coil. Then, we’ll use a formula to calculate the cooling coil capacity.<\/p>\n\n\nUsing Psychrometric Chart to Size AHU Cooling Coil<\/h2>\n\n\n\n