# How to Calculate Chilled Water Pump Head?

##### Joseph Hebert
Owner at - HVAC Buster

Joseph is an HVAC technician and a hobbyist blogger. He’s been working as an HVAC technician for almost 13 years, and he started blogging just...Read more

Chilled water is circulated through a building’s HVAC system to keep the air temperature cool and comfortable. The chilled water is produced by a chiller, which uses a refrigeration process to remove heat from water. The cooled water is then circulated through a series of pipes and pumps to the air handling units (AHUs) that make up the HVAC system.

To calculate the head required for a chilled water pump, you need to know the following: • The total dynamic head (TDH) of the system – this is the sum of the static head, friction loss, and velocity head in the piping system • The flow rate of chilled water through the system

• The desired operating point on the pump curve With this information, you can use the following equation to calculate pump head:

• Determine the system flow rate in gallons per minute (GPM)
• Convert the GPM to cubic feet per second (cfs)
• This can be done by multiplying the GPM by 0
• Find the head loss of the system in feet per 100 feet of piping (f/100 ft)
• This can be done by looking up the head loss curve for your specific piping system and reading off the value at your design flow rate
• The static head is simply the vertical height difference between your pump’s discharge point and suction point
• The dynamic head takes into account friction losses from fluid movement and is calculated using the following formula: Dynamic Head = Flow Rate x Friction Loss / 2g where g is acceleration due to gravity (32
• 2 ft/s^2)
• Use this total head value to select a suitable pump for your application from a manufacturer’s performance curve chart

## How Do I Calculate Chilled Water Pump Head

If you want to calculate the head of a chilled water pump, there are a few things that you need to know. The first is the static head, which is the vertical distance between the centerline of the pump and the highest point in the piping system. The second is the dynamic head, which is the difference in elevation between the liquid level in the suction tank and discharge tank.

## What Factors Influence Chilled Water Pump Head Calculation

As with any pump head calculation, there are a few factors to consider when calculating the head for a chilled water pump. These include the fluid being pumped (water or glycol), the temperature of the fluid, the flow rate, and the system pressure. The first step is to determine the density of the fluid being pumped.

This can be done using a simple online calculator or by looking up the density in a tables (such as those found in most engineering handbooks). Once you have the density, you can then calculate the mass flow rate of the fluid. This is simply the volume flow rate multiplied by the density.

Next, you need to determine what type of pipe system you are using. The two most common types for chilled water systems are closed loop and open loop. Closed loop systems will have a higher pressure than open loop systems due to their design.

This means that you will need to use a different equation to calculate head loss for closed loop systems. Once you have determined all of these factors, you can then begin to calculate Pump Head using one of several methods. The most common method is called “the Affinity Laws”.

These laws state that various pump parameters are related by mathematical equations. By plugging in your specific values for each factor, you can solve for Pump Head using these equations.

## What are the Benefits of Calculating Chilled Water Pump Head

Calculating the head of a chilled water pump is important for many reasons. The most important reason is that it allows you to determine the correct size and type of pump for your application. It also allows you to troubleshoot problems with your current setup and make adjustments as needed.