HVAC Calculation: Learn About CFM, BTU/HR, TMBH & SMBH

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To calculate CFM for HVAC systems, it's essential to consider internal and skin loads, often using specialized software or psychrometric charts for accurate results. A ton of cooling is equivalent to 12,000 BTU/hr, which is a standard measure in the industry. TMBH refers to total MBH, indicating total heating or cooling capacity in thousands of BTU/hr, while SMBH stands for sensible MBH, focusing on temperature change without accounting for moisture. Mentorship from experienced engineers is highly recommended for those new to the MEP field to enhance understanding and skills. Mastering these calculations is crucial for effective HVAC design and operation.
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Dear all
I am working in MEP field but no experience so I need your helps how find out an area cfm calculation and what is the ton of Ac given, what is the power how to find this calculation ..
BTU/HR - British Thermal Unit /Hr.

CFM - Cubic Feet per Minite

TMBH - ?

SMBH - ?

what is mean by TMBH and SMBH ?
 
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Welcome to PF.

If you're working in the HVAC field, don't you have a more experienced engineer to mentor you? There is no other effective way to become an HVAC engineer. Anyway...

The capacity required (CFM at a certain temperature) is usually calculated using software for the internal and skin (walls, windows) load and fraction of fresh air and its temperature. Unless it is 100% outside air and a high volume (like for a lab), then it is just calculated using a psychrometric chart.

A ton of cooling is 12,000 BTU/hr

TMBH is total MBH (MBH is 1000 BTU/hr)
SMBH is sensible MBH (the part of the capacity related to temperature change, not condensation of water.
 

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