Heat Load Calculator — Sensible & Latent Heat | PsychroCalcLab

Calculate sensible, latent, and total heat load for HVAC systems. Determine the Sensible Heat Ratio (SHR) for precise cooling coil sizing.

How to Use

  1. Enter air flow rate and supply/return temperatures.
  2. The results update automatically as you change the input values.
  3. Review the calculated value and the engineering notes shown below the result.

Frequently Asked Questions

What is Sensible Heat Ratio (SHR)?

SHR is the ratio of sensible heat to total heat. It tells you how much of the cooling energy is spent lowering temperature versus removing moisture.

How does airflow affect heat load?

Higher airflow increases the total heat transfer capacity. The heat load calculation relies heavily on the mass or volume flow rate (CFM or L/s) of the air.

Why calculate both sensible and latent heat?

If you only account for sensible heat, your system won't remove enough moisture, leading to a cold but clammy and uncomfortable environment.

Can this be used for residential HVAC sizing?

Yes, while typically used for commercial air handler calculations, these exact same thermodynamic principles apply to sizing residential air conditioners and heat pumps to ensure they are matched perfectly to the cooling load.