Buying and Installing an EarthLinked® Geothermal System—the Process

When considering EarthLinked® DX for your home or business, it's very helpful to know what to expect, what steps are required, and how to sort fact from fiction. Let us help you, with this step-by-step guide, understand the process of buying and installing EarthLinked®.

1. Load Calculation

The first step is performing a Manual J load calculation. A load calculation is a process in which a "snapshot" is taken of your project plans, taking into account the materials used in its construction. An accepted industry standard, the load calculation includes, but is not limited to, the following components (with particular focus on R-values):

  • Exterior walls
  • Roof structure/type
  • Foundation, slab, crawl space
  • Insulation
  • Windows & Doors (type, number, placement)
  • Room sizes & total square footage
  • Earth temperature in your area
  • Climate
  • Heat loss & gain

Most HVAC contractors are very familiar with Manual J load calculations yet many do not perform one when sizing a system. It is a fairly complex process, but should always be done—especially in the case of geothermal system sizing. All EarthLinked® dealers/installers are required to submit the Manual J load calculation findings with each order to insure proper system sizing, operation, and maximum efficiency.

Failure to perform a Manual J load calculation can result in oversized or undersized systems, both of which present inherent problems in the long term. An undersized system will have to struggle to maintain a comfortable indoor temperature which means it will run for prolonged periods. This condition also has the potential to dramatically shorten the life of the system. On the other hand, an oversized system will run more frequently as it attempts to satisfy the temperature quickly, turning on repeatedly in short cycles. Not only is "short cycling" hard on the system, it also reduces efficiency by requiring more electricity to keep the home or office comfortable.

So regardless of the type of geothermal system you're considering, insist on a Manual J load calculation. If your contractor doesn't utilize them in its sizing and bid process, keep looking for one who does. In the case of new construction, another helpful tip is to wait until all changes have been made to your plans. By doing so, you won't run the risk of those changes adversely affecting the load calculation at the last minute.

2. Site Evaluation

Site evaluation is the second step in planning your system installation. It not only impacts the type of earth loop installation best suited to your project, but also factors heavily into the overall cost of the EarthLinked® system.

There are three options for earth loop installation: horizontal, diagonal and vertical. Depending on your geographical location and existing geological conditions, you may be able to select from all three. In areas of the country where rock is prevalent, the drilled bore holes of the diagonal and vertical applications—while more expensive—are most common. Drilling costs vary from region to region, so be sure to check with your EarthLinked® dealer/installer for local drilling rates. The horizontal earth loop application is the least expensive to install, largely because in most areas of the country it's less expensive to excavate and backfill than to drill.

3. Installation

Aside from the earth loop portion of the DX installation, it's very similar to an air source installation with regard to the ducting and component installation. One major difference between DX and air source, however, is that the EarthLinked® compressor unit can be installed indoors or outdoors—whichever you prefer! Because it doesn't rely on air circulation, as do air source systems, the EarthLinked® compressor unit can be placed in a basement, mechanical room, attic area or garage.

 

©2004. All rights reserved. All images are copyrighted and may not be reproduced in any form without permission from Home Energy, Inc.