Geothermal Heating Issues

Airflow

• If the geothermal heat pump has an airflow of less that 350 cm per ton, the performance of the system will deteriorate. The solution might be as simple as increasing the speed of the fan. Low airflow could come from dirty coils or filters or the problem could be more systemic requiring modifications to the ductwork.

Location

• A geothermal heat pump has a maximum outdoor sound rating of 7.6 bels. If the unit is excessively noisy, the problem could be its location. You should mounted it on a noise-absorbing base and install it away from windows and adjacent buildings. The location can also have a significant impact on the efficiency of the pump as well.

Open-Loop Systems

• Open-loop geothermal systems can be more problematic than closed-loop or conventional systems. They require a continual supply of clean water to be cost effective so they are generally limited to areas on the coast, next to a lake or river or areas where there is a high water table. They must also have a suitable method of returning the water back into the environment.

  Some systems use a surface well; others return the water to the source it came from or build a recharge well that will inject the water back into the ground. While the only difference between the water going in and the water going out is a slight increase in temperature, there is a risk of contamination if the wells are poorly designed or improperly installed.

Closed-Loop Systems

• Many closed-loop systems use an antifreeze or refrigerant mixture in cold climates to keep the water inside the loop from freezing. This can create an environmental concern because, while the solution has been classified in the A1 Safety Group by the American National Standard (the safest category), it could produce chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs), which contribute to ozone depletion.

  However, the system is sealed at the factory, just like a refrigerator, and the polyethylene piping that carries the fluid is guaranteed for 20 to 50 years. The increased viscosity of the antifreeze solution could also make the system work harder.

Cost

• The initial up-front cost can be higher than conventional systems. In the past, it took an average of 7 years to recoup the upfront cost of a geothermal system. However, the government offers substantial tax rebates and incentives so that today, the estimate is 4 years to recoup the initial investment. (Source 2)