Calculate sensible heat ratio (SHR) from sensible heat load and total heat load in kW or BTU/h, or find the missing value with unit conversion.

SHR Sensible Heat Ratio Calculator
Enter any two compatible values to calculate the remaining values.

SHR Sensible Heat Ratio Formula

The sensible heat ratio, or SHR, compares sensible heat to total heat. Total heat is the sum of sensible heat and latent heat.

SHR = SH / TH
TH = SH + LH
SHR = SH / (SH + LH)

For percent form:

SHR% = SHR * 100

The calculator can also solve missing values from compatible pairs:

LH = TH - SH
SH = TH - LH
SH = SHR * TH
TH = SH / SHR
TH = LH / (1 - SHR)
  • SH = sensible heat
  • LH = latent heat
  • TH = total heat
  • SHR = sensible heat ratio as a decimal, usually between 0 and 1
  • SHR% = sensible heat ratio as a percentage

You can enter heat values in any consistent unit, such as Btu/h, kW, or tons of cooling. Sensible heat, latent heat, and total heat must use the same unit.

If you enter sensible heat and latent heat, the calculator adds them to get total heat, then divides sensible heat by total heat to get SHR.

If you enter total heat with either sensible heat or latent heat, the calculator subtracts to find the missing heat value and then calculates SHR.

If you enter SHR with total heat, sensible heat, or latent heat, the calculator rearranges the same formulas to solve the missing values.

Typical SHR Values and What They Mean

SHR SHR Percent Meaning
0.50 50% Half of the total load is sensible heat and half is latent heat.
0.70 70% Common mixed cooling load with both temperature and humidity removal.
0.80 80% Mostly sensible cooling, with less moisture removal.
0.90 90% Very high sensible load and low latent load.

Compatible Input Pairs

Values You Enter Values Calculated
Sensible heat and latent heat Total heat, SHR, and SHR percentage
Sensible heat and total heat Latent heat, SHR, and SHR percentage
Latent heat and total heat Sensible heat, SHR, and SHR percentage
SHR and total heat Sensible heat and latent heat
SHR and sensible heat Total heat and latent heat
SHR and latent heat Total heat and sensible heat

Example Problems

Example 1: Find SHR from sensible and latent heat

You have a sensible heat load of 24,000 Btu/h and a latent heat load of 6,000 Btu/h.

TH = 24000 + 6000 = 30000
SHR = 24000 / 30000 = 0.8

The SHR is 0.8, or 80%.

Example 2: Find sensible and latent heat from SHR and total heat

You have a total heat load of 40,000 Btu/h and an SHR of 0.75.

SH = 0.75 * 40000 = 30000
LH = 40000 - 30000 = 10000

The sensible heat is 30,000 Btu/h and the latent heat is 10,000 Btu/h.

FAQ

What is a good sensible heat ratio?

There is no single good SHR for every system. A higher SHR means more of the cooling capacity goes toward lowering air temperature. A lower SHR means more of the cooling capacity goes toward removing moisture. Many comfort cooling applications are often around 0.70 to 0.80, but the right value depends on the space and humidity load.

Can SHR be greater than 1?

No. For normal cooling load calculations, SHR should be between 0 and 1. An SHR of 1 means all the load is sensible heat and there is no latent heat. A value greater than 1 usually means the inputs are not physically consistent.

Do the heat values need to be in Btu/h?

No. You can use Btu/h, kW, tons, or another heat rate unit. The key is consistency. Sensible heat, latent heat, and total heat must all use the same unit for the ratio to be correct.