Ground Loop Sizing Calculator

Calculate bore depth and loop length for a geothermal heat pump.

Heating Load

BTU/hr

Cooling Load

BTU/hr

Ground Temperature

°F

Heat Pump COP

Soil Conductivity

BTU/(hr·ft·°F)

Loop Type

Tab to move between fields

Total Bore/Trench Length

700 ft

≈ 9 tennis courts

Number of Bores/Loops

Total Loop Pipe1,400 ft

System Size4 tons

Ground Heat Exchange45,000 BTU/hr

How to Use This Calculator

Enter the building's peak heating load in BTU/hr.
Set the ground thermal conductivity for your soil type.
Input the desired entering water temperature (EWT) to the heat pump.
Enter the loop pipe diameter and flow rate per ton.
Review the total loop length in feet and the recommended trench or borehole configuration.

How the result changes with Ground Temperature

Heating Load: Peak heating load in BTU per hour.
Cooling Load: Peak cooling load in BTU per hour.
Ground Temperature: Undisturbed ground temperature at depth.
Heat Pump COP: Coefficient of performance of the heat pump.
Soil Conductivity: Thermal conductivity of the soil. 0.5 dry sand, 1.0 average, 1.4 wet clay.
Loop Type: Ground loop installation type.

Identify Input Parameters
4 parameters
Heating Load = 48000, Cooling Load = 36000, Ground Temperature = 55, Heat Pump COP = 4 = 6 input(s) provided
Calculate Total Bore/Trench Length
Total Bore/Trench Length
700 = 700
Calculate Number of Bores/Loops
4 = 4
Calculate Total Loop Pipe
Total Loop Pipe
1400 = 1400
Calculate System Size
System Size
4 = 4