Enter the tank head (ft) and the density of fluid (lb/ft^3) into the calculator to determine the Expansion Tank Pressure. 

Expansion Tank Pressure Formula

The following formula is used to calculate the Expansion Tank Pressure. 

Ptank = Ht * D / 144
  • Where Ptank is the Expansion Tank Pressure (psi)
  • Ht is the tank head (ft) 
  • D is the density of fluid (lb/ft^3) 

To calculate the expansion tank pressure, multiply the tank head by the density, then divide by 144.

How to Calculate Expansion Tank Pressure?

The following two example problems outline how to calculate the Expansion Tank Pressure.

Example Problem #1:

  1. First, determine the tank head (ft). In this example, the tank head (ft) is given as 3.5.
  2. Next, determine the density of fluid (lb/ft^3). For this problem, the density of fluid (lb/ft^3) is given as 1225.
  3. Finally, calculate the Expansion Tank Pressure using the equation above: 

Ptank = Ht * D / 144

Inserting the values from above and solving the equation: 

Ptank =3.5 * 1225 / 144 = 29.77 (psi)


Example Problem #2: 

Using the same process as above, first define the variables required by the formula. In this case, these values are:

tank head (ft) = 5

density of fluid (lb/ft^3) = 1055

Entering these values yields:

Ptank = 5 * 1055 / 144 = 36.631 (psi)