Issue:
How to calculate volume of water in a system?
Resolution:
 Determine what needs to be calculated.
 Square Feet for measuring area
 Gallons for measuring volume
 Calculate the volume of liquid pipes can hold. The volume can be determined by multiplying the crosssectional area by the length
 Determine the pipe size ( d=diameter inches ) of all pipe(s) in the system.
 Determine the length ( L=length feet ) of all pipe size(s) in the system.
 Gallons (volume) of a pipe using US gallons is 7.48 gallons / cubic foot
 In square inches, calculate the cross sectional area of the pipe.
 Determine the Radius ( r=radius inches ) of the pipe: r = d/2
 Determine the Area: area = 3.14 r^2
 Volume of a pipe in cubic feet: Volume (cubic feet) = ( area L ) / 144 (144 square inches in one square foot)
 Gallons (volume) of a pipe using US gallons is 7.48 gallons / cubic foot
 Therefore the Gallons (volume of liquid) in a piping system is: Volume (cubic feet) 7.48 (gallons/cubic foot)

For example: The system has 100 ft. of 4" ID Plastic Pipe. The chiller has a 50 gpm pump which was flow was determined to be correct. The minimum amount (volume) of water in the system should be 2 x GPM to ensure proper loop time. For this example, is there enough water in the system?
 Based on the above equations, the area = 3.14 x 4 = 12.56 square inches
 Volume = (12.56 x 100)/144 = 8.721 (cubic feet)
 Gallons (volume of liquid) = 8.72 x 7.48 = 65.24 gallons
 Therefore 65.24 < 2 x 50 ; 65.24 < 100. Therefore there is NOT enough water in the system to meet minimum volume of water requirements for 2 x GPM as the minimum volume of water in the system.
.
Notes:
This can be used for any type of pipe; all that is needed is the inside diameter of the pipe and length of pipe.
Other Question/Problem/Cause Statements:
 Volume of Water in a system?
 Volume of Water in a Pipe?
 Square Feet of Pipe to Gallons?
 What is the volume of water is a system?
 How do I determine the volume of water in a system?
Facts:
 This does not included storage or water in any heat exchanger.
 AirCooled Chiller (Pueblo)
 WaterCooled Chiller (Pueblo)
Original HUB Document : DOC86198
WARNING:
Information in this article is intended for use by individuals possessing adequate backgrounds of electrical and mechanical experience and who comply with all federal, state, and local laws, rules, orders, or regulations related to the installation, service, or repair of a heating or central air conditioning product. Any attempt to install, service, or repair a heating or central air conditioning product may result in personal injury and/or property damage. The manufacturer or seller cannot be responsible for the interpretation of the information contained herein, nor can it assume any liability in connection with its use.