Features

• Calculates Pipe Loop Lengths and Pressure Drops
• Follows OSU and ASHRAE Calculation Procedures
• Handles Horizontal, Vertical, and Slinky Systems
• Includes Loop Builder tool
• Prints Bill of Materials with Material and Labor Costs
• Supplied with Data on All Common Soil Types
• References Built-in Pipe & Fitting Data
• References Built-in Heat Pump Data
• Automatically Adjusts Heat Pump Performance Data
• References Built-in Weather Data on over 200 Cities
• Computes Minimum Purge GPM and Pressure
• Links to the RHVAC Load Calculation Program

Overview

Earth Coupled Analysis (ECA) quickly calculates the required pipe loop length necessary for heating and cooling a building with a given heat pump, soil, and weather conditions. ECA can analyze both vertical and horizontal pipe systems. In addition to computing pipe lengths, ECA can also generate a complete bill of materials with a cost estimate of the required labor and materials. Pressure losses through the equipment room, heat pump, header pipe, and the earth coil are computed along with the purge pressure and flow requirements. Heating and cooling runtime fractions are computed on a temperature bin basis. ECA is supplied with built-in data on many pipe types including polyethylene, polybutylene, copper, iron, and others. However, data on all pipe types can be revised and additional pipe types can be defined as well. Equivalent length data for fittings on all pipe types is also included. ECA comes with a heat pump data file containing performance data on models from several manufacturers. There is also provision for the user to add heat pump data from any other manufacturer. Data on all soil types listed in the ASHRAE manual are built-in to ECA, and the user can add more. Weather data for over 200 cities are built-in, and the weather data can be revised or added to as much as desired.

Calculation Method

The ECA Program follows the methodology described in the Design/Data Manual for Closed-Loop Ground-Coupled Heat Pump Systems published by the American Society of Heating, Refrigerating,and Air Conditioning Engineers (ASHRAE). All results computed by the program can be easily verified by hand to be in accordance with ASHRAE.

Program Input

The ECA program s a true Windows program complete with toolbars and hyperlinked help. All input data is checked at the time of entry so that no improper data can be entered. Two types of data are requested: general project data and specific system data. The general project data includes the project name and location, client and designer names, the building heating and cooling loads, the summer and winter design conditions, and the soil thermal properties. The system data includes the system type (vertical or horizontal), pipe material, pipe sizes, fitting data, antifreeze percentage, minimum and maximum entering water temperatures, series or parallel flow, and heat pump capacity, COP and EER values. Much of the input data for the heat pump, soil and weather conditions, and pipe materials can be automatically looked up by ECA. Input sheets are provided for the easy organization of your data.

Program Output

The ECA Program provides the following four basic output reports: general project data, pipe length calculations, bill of materials, and pressure drop calculations. In addition to these reports the built-in pipe data, fitting data, and soil data can be printed. The user can specify exactly what reports are to be printed, the left hand margin, and starting page number. All reports can be printed to the screen or printer.