GLHEPRO for Windows Img00001.gif (1033 bytes)

The Professional Ground Loop Heat Exchanger Software

Version 4.0 now available!

Overview | New Features | Versions | Shipping | Ordering | Registration | Manual | Support | FAQs


This site has now been updated with a list of GLHEPRO Frequently Asked Questions (FAQs). The FAQ page will also serve as a listing of known bugs and other issues. Additionally, instructions on ensuring you receive the latest updates to GLHEPRO are located there.


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GLHEPRO was developed as an aid in the design of vertical borehole-type ground loop heat exchangers used in geothermal heat pump systems. While GLHEPRO may be used for residential system design, it is aimed at commercial systems. The heat exchanger may be composed of any number of boreholes arranged in various configurations.

GLHEPRO performs three different tasks:


Simulation (for up to 100 years) of ground loop heat exchangers to determine monthly average and peak heat pump entering and exiting fluid temperatures, as well as power consumption of the heat pump.


Determination of the required borehole depth to meet user-specified minimum and maximum heat pump entering fluid temperatures.


Sizing of hybrid ground source heat pump (HGSHP) systems by determination of the required borehole depth and necessary supplemental heat rejecter (cooling tower, fluid cooler) or heat extractor (boiler) size.


GLHEPRO is based on the methodology developed by Eskilson at the University of Lund in Sweden, considered by Dr. Spitler to be the best currently available methodology.

A technical paper which describes GLHEPRO v3.0 may be found here. Most of the discussion in this paper still applies to GLHEPRO v4.0. The new GLHE model, which includes improved borehole thermal resistance calculations and consideration of thermal mass, is described by Xu and Spitler (2006). Additionally, the manual for GLHEPRO v4.0 may be found here.

GLHEPRO requires four basic sets of input data:


Monthly and monthly peak heating and cooling loads on the heat pumps. These are obtainable from programs such as HVAC Load Calculations for Windows, Trane Systems Analyzer, and other similar programs. GLHEPRO has an interface to the above-named programs which automates the data transfer. For other programs, the loads must be typed in manually.


Ground thermal properties. GLHEPRO has a small database of ground thermal properties for a few different ground types. For larger jobs, an in situ test is recommended, using the in situ methodology developed at Oklahoma State University.


Ground loop heat exchanger information. The user must select a borehole configuration and specify some related additional information - borehole diameter, borehole spacing, grout and piping properties, and fluid type and flow rate. Open and closed rectangle, line, U-shaped, L-shaped, and stacked L-shaped configurations are available; additionally, the Large Rectangle option can be purchased, which provides additional borehole configurations up to 900 boreholes.


Heat pump information. GLHEPRO has a database of heat pump types from most manufacturers. Any models not available in the database may be added by the user using commonly available catalog data.


GLHEPRO offers an easy-to-use Windows interface. The borehole configurations are chosen from one of the following screens, depending on your version:

Regular borehole field selectionLarge rectangular field selection
GLHEPRO borehole configuration selection window GLHEPRO large rectangular field selection window

Heat pumps are selected from a database of heat pumps using this screen:

GLHEPRO heat pump selection window


New Features

New features for Version 4.0 include:


Capability to model rectangular borefields up to 900 boreholes.


Sizing of ground loop heat exchanger and supplemental heat source/sink as part of a hybrid ground source heat pump system.


More accurate calculation of borehole thermal resistance, including thermal mass effects.


Revamped fluid property routines. The working fluid can now be specified in terms of composition and concentration.


Addition of double U-tube and concentric tube heat exchangers.


Marked improvement of output reporting. Users can specify what information is reported, and have the option of creating a Microsoft Excel-compatible .CSV file.


International ground temperatures are available for several locations, and users may enter additional locations.


Heat pump database has been greatly expanded.


Versions Available

GLHEPRO is now available in three different versions:

GLHEPRO 4.0-120: Contains 307 different borehole configurations between 1 and 120 boreholes. Configurations include lines, L-shaped fields, U-shaped fields, open rectangular fields and rectangular fields. The cost of a single license is $525.

GLHEPRO 4.0-LRO: Contains only large rectangular borefields, 100 boreholes and larger. The algorithms used to create the g-functions were based on configurations of up to 400 boreholes in size. Beyond 400 boreholes, the program extrapolates the results. The cost of a single license is $525.

GLHEPRO 4.0-400+: Contains all configurations in GLHEPRO 4.0-120 and GLHEPRO 4.0-LRO. The cost of a single license is $725.


Shipping Options

The purchase price includes delivery in one of the forms below. When ordering, users should specify which form of delivery they prefer.

Domestic shipping


First Class Mail (default). Cost included in purchase price.


Download. Cost included in purchase price. Download instructions are sent via email as soon as payment has been verified. The download includes all of the same files (including the manual) as the mailed CD.

International shipping


First Class Mail International (default). Cost included in purchase price.
Please note that the U.S. Postal Service states that normal transit time for most international destinations is 6-10 days (without any holdup in Customs); however, some packages have taken as long as 23 days. Furthermore, packages sent by the U.S. Postal Service cannot be tracked, so we cannot answer queries regarding the status of your package once it has been mailed.


Fed-Ex International, or current OSU-contracted shipper. The cost is $75 (USD), paid by a US-dollar denominated check. We're sorry, but we are unable to accept payment via credit card or wire transfer for these charges.
Please note that packages sent by Fed-Ex and similar shippers are trackable, so we can check the status of your package in transit.


Download. Cost included in purchase price. Download instructions are sent via email as soon as payment has been verified. The download includes all of the same files (including the manual) as the mailed CD.


Ordering Information

GLHEPRO for Windows can be obtained through IGSHPA.  An order form and ordering instructions that cover most cases are here. A more complete price list that covers university pricing and cases such as upgrades to previous additional licenses, is available here. A demonstration version is available for $50. To order GLHEPRO, please call or send your order form to:

International Ground Source Heat Pump Association (IGSHPA)
1201 S Innovation Way, Suite 400
Stillwater, OK 74074
Phone: 1-800-626-4747 or (405) 744-5175
Fax: (405) 744-5283



Please click here to register your GLHEPRO for Windows software.


Technical Information and User Support

For technical information on the software, or user support, please contact:

Rachel Grundmann

School of Mechanical and Aerospace Engineering
Oklahoma State University
218 Engineering North
Stillwater, Oklahoma 74078-0545
Phone: (405) 744-3831


For fastest response, email is preferred.

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