ECA (Earth Coupled Analysis) is a Windows application for designing closed-loop geothermal heat pump systems. It calculates required pipe loop lengths and fluid pressure drops for horizontal, vertical, and slinky ground heat exchangers, following Oklahoma State University (OSU) and ASHRAE procedures. The program includes built-in data for common soil types, pipe and fittings, geothermal heat pumps, and weather for 200+ cities, and automatically adjusts heat pump performance data for design conditions. ECA provides a Loop Builder tool to configure loop fields, computes minimum purge flow (GPM) and pressure for flushing, prints a bill of materials with material and labor costs, and links with the RHVAC load calculation program.

Key Features

Standards-based geothermal calculations Design ground loops with vetted procedures.

• Calculates pipe loop lengths and pressure drops per OSU and ASHRAE methods.
• Handles horizontal, vertical, and slinky loop configurations.

Built-in engineering data and tools Reduce data entry and improve accuracy.

• Includes soil type properties, pipe/fitting libraries, and heat pump data with automatic performance adjustments.[4]
• Provides weather data for over 200 cities and a Loop Builder tool for field layouts.

Construction-ready outputs Support installation and commissioning.

• Prints a bill of materials covering materials and labor for estimating and procurement.
• Computes minimum purge GPM and pressure for flushing and startup checks.

Benefits

Accurate geothermal loop sizing Improves system efficiency and reliability.

• Uses OSU/ASHRAE methods to right-size loop lengths and assess pressure drops.
• Built-in soil, equipment, and weather data align designs with local conditions.

Faster design-to-install handoff Streamlines documentation and setup.

• Bill of materials supports estimating and purchasing.
• Purge flow/pressure calculations aid commissioning and reduce field rework.