Geo-Direct® vs. Water Source

Earth Loop Differences

• No groundwater contamination. • No Secondary or intermediate heat   exchanger. • No lost energy in exchange process. • Refrigerant in ground coil actually   goes through a phase change process   with high energy transfer.	• Propylene Glycol must be added for   pump lubricity and to prevent   freezing of pipes. • Refrigerant to water heat exchanger    required for system to function. • Lost energy in exchange process. • Majority of phase change occurs in    secondary heat exchanger, low    energy transfer.
Uses more refrigerant. • Requires avg. of 6 Lbs per system   ton. • R-22 refrigerant is safe by EPA   standards. • Mineral oil is used to lubricate   compressor. • No need for make up water due to   leakage or evaporation.	Uses less refrigerant. • Requires large amounts of water plus   30% glycol solution to charge system. • When combined with labor to install    and purge loop field, actual cost can    be higher. • Make-up water required.
Less Invasive   • If a leak occurs, the location is   determined by pressurizing system   with mixture of Freon and Nitrogen   and simple refrigerant leak detectors.   • Indoor location - Nitrogen purge   while brazing leak area. Pressure   check, evacuate and recharge system.   • Outdoor location - A shovel is used to   uncover manifold pit, (Installing   Contractor, Sales Rep and   Manufacturer have records of   manifold location) leak located. If   leak is in manifold joint, simply   re-braze. If it is determined that the   leak is within the actual loop, many   times the loop can be isolated, system   recharged and put back in operation   without drilling or excavation.   • In either scenario if loop replacement   is required, the impacted land needing   to be disturbed is 50-75% less.	More Invasive   • First of all leakage occurs inherently   due to the pump and clamps sealing   mechanisms. That is why a make up   reservoir is installed with this type of   system. If the leak is not excessive,   most often you will be told to just   add make-up water. (Ongoing   maintenance that you spent money to   avoid.) If an unacceptable leak   occurs:   • Indoor location - A visual inspection   will determine location. Many times   the clamps used to secure the pipe   with begin to leak; a simple tightening   may be all that is needed.   • Outdoor location - Large areas of the yard will may have to be dug up with a backhoe or similar machine to locate source of leak. (Assuming accessibility is not an issue.) Isolation of a loop is not an option. In either location, if leak is in a fused joint then potentially the entire water/glycol charge will have to be removed, pipe refused, system refilled and purged.

   

Geo-Direct® Direct Exchange	Conventional Closed Loop Water Source
Uses no water. • No Secondary water pump. • No additional energy to operate pump. • No pump maintenance or replacement.	Uses water/glycol solution.   • Must have secondary water pump. • Stated energy costs are not realistically included in efficiency ratings.