About GeoThermal Heating & Cooling
This page will inform you on the function and efficiency
of modern Geothermal Heating and Cooling. Geothermal units are the most efficient
heating and cooling option available. Also, the cost of geothermal units are more
costly but can pay for themselves using the savings they will create in your energy
bills. Also, A geothermal system and piping can increase the value of your home
and property. Once a geothermal loopfield is installed - this loopfield is an energy
source (or energy plant) that will last for many years. A properly installed geothermal
system and loopfield will provide energy savings and features such as hot water
heating that other conventional systems do not provide.
Advanced Heating and Cooling offers Florida Heat Pump,
Bosch and Climatemaster brand geothermal heating and cooling equipment. Advanced Heating & Cooling
is a Bosch certified Geothermal Technician and Installer. Advanced Heating &
Cooling can calculate loop loads and provide every aspect of the Geothermal system
installation. We use experienced, licensed, bonded, and insured drillers that take
concern of our customers property and minimize any damage to your landscaping.
About Geothermal Units
A geothermal heat pump system is a central heating and/or air conditioning system
that actively pumps heat to or from the shallow ground. It uses the earth as either
a source of heat in the winter, or as a coolant in the summer. This design takes
advantage of moderate temperatures in the shallow ground to boost efficiency and
reduce operational costs.
Geothermal heat pumps are also known by a variety of other names, including geoexchange,
earth-coupled, earth energy, ground-source or water-source heat pump. The engineering
and scientific community tend to prefer the terms "geoexchange" or "ground-source
heat pumps" because very little of the heat originates from true geological
sources. Instead, these pumps draw energy from shallow ground heated by the sun
in the summer. Genuine geothermal energy from the core of Earth is available only
in places where volcanic activity comes close to the surface, and can usually be
extracted without the help of a heat pump.
Like a refrigerator or air conditioner, these systems use a heat pump to force the
transfer of heat. Heat pumps can capture heat from a cool area and transfer it to
a warm area, against the natural direction of flow, or they can enhance the natural
flow of heat from a warm area to a cool one. The core of the heat pump is a loop
of refrigerant pumped through a vapor-compression refrigeration cycle that moves
heat. Heat pumps are always more efficient than pure electric heating, even when
extracting heat from air.
A Geothermal Heat Pump circulates water (also antifreeze) through high-density polyethylene
(HDPE) pipe. The water picks up the warm or cold temperature of the ground depending
on the season and is pumped through the plumbing by a water pump that carries the
heated or cooled liquid to the geothermal unit. Here the temperature of the water
is picked up by the regrigerant system of the geothermal unit by a tube-in-tube
coil that has refrigerant lines located inside of the coil that water that is passing
Geothermal units can incorporate a DeSuperheater to heat cold water to serve as a water heater for your home.
Components of a Geothermal Unit
Indoor Coil - The coil that usually functions as an evaporator in a normal
Outdoor Coil - The coil that usually functions as a condenser in a normal
Reversing Valve - The valve that directs the flow of refrigerant to the appropriate
coil based on which mode the heat pump is in, Heating or Cooling.
High-density polyethylene (HDPE) pipe - Special lines that are installed
in ponds or the earth to absorb the warmth or coldness of the medium it is located
Compressor - The component that pumps the refrigerant throught the system.
Indoor Fan Motor - The Fan Motor that circulates air through the indoor coil
and supply side of the duct system.
Outdoor Fan Motor - The Fan Motor that pulls air through the outdoor coil
to cool the refrigerant or condense the refrigerant and remove heat from the refrigerant.
Bi-directional Expansion Valve - A metering device that is capable of metering
refrigerant or bypassing the metering section depending on the direction the refrigerant
Check-Valve - Restricts or allows flow of refrigerant depending on which
way the refrigerant is flowing.
Water Pump - An electric motor that pumps water (and antifreeze) through
the plumbing system of the geothermal unit.
Antifreeze or Brine - The fluid that is added to water that circulates through
the geothermal units plumbing system to keep the water from freezing.
Efficiency of a GeoThermal Unit
A Geothermal Units efficiency depends on the temperature of the outside ambient
air. A Geothermal Units can absorb heat from the outside ambient air down to a temperature
of absolute zero, -460 degrees Fahrenheit. Geothermal Units are really efficient
based on the fact that the Heat Pump uses the mechanical refrigeration system to
absorb warmth and coldness from the ground or a pond. Electric resistive heaters
use a vast amount of electricity compared to a Geothermal Unit in order to heat
a home. Gas Units are efficient but the recent rise of gas and fuel prices make
these units much more expensive to operate than a Geothermal Unit.
ENERGY STAR - Products/Homes/Buildings that earn the ENERGY STAR prevent
greenhouse gas emissions by meeting strict energy efficiency guidelines set by the
U.S. Environmental Protection Agency and the U.S. Department of Energy. To learn
more, please visit www.energystar.gov.
EER - The EER is the efficiency rating for the equipment at a particular
pair of external and internal temperatures. SEER rating more accurately reflects
overall system efficiency on a seasonal basis and EER reflects the system’s
energy efficiency at peak day operations.
SEER - This is a measurement of the efficiency of cooling products. The U.S.
Government's minimum efficiency level is 13 SEER for split systems and packaged
units. The higher the SEER, the more efficient the cooling product. SEER stands
for Seasonal Energy Efficiency Rating.
HSPF - This is a measurement of a heat pump's heating efficiency. There
is no governmental minimum rating. The higher the HSPF, the more efficient the heat
pump's heating performance. HSPF stands for Heating Seasonal Performance Factor.
COP - Coefficient Of Performance. A ratio that compares a heat pump system's
heating efficiency to that of electric resistance heat. For example, a heat pump
system with a COP of 3.0 provides heat at 3 times the efficiency of electric resistance
heat. A heat pump's system COP will decrease as outdoor temperatures drop, eventually
providing little or no efficiency advantage over electric resistance heat - and
that's when your auxiliary heat strips start to heat your home.
A Note About Efficiencies: When you're getting ready to replace an older
heating or cooling system, it's very important for you to get a Load Calculation
done by your dealer/contractor. The greater the difference between the efficiency
of your old system to the new system, the more likelihood that the dealer will recommend
a smaller sized unit. This should not cause alarm, as the dealer, by running a Load
Calculation, will be able to accurately size the system to the load in your home.
It can be quite detrimental to equipment if the units are too large for the load
in your home - they can start to "short cycle" (they run often but for
very short periods of time, because they are pumping out too much heat/cooling and
reach the thermostat's setting too quickly), which can shorten the life of the
Operation of a GeoThermal Unit in Cooling Mode
The Geothermal Unit operates normally in Cooling Mode as a normal air-conditioner.
The Heat Pump uses the indoor coil as an evaporator and the outdoor coil as a condenser
in the Cooling Mode. The reversing valve is energized or de-energized based on the
manufacturers specification to direct the flow of refrigerant to the appropriate
Operation of a GeoThermal Unit in Cooling Mode
Operation of a GeoThermal Unit in Heating Mode
The Geothermal Unit operates in a reverse cycle in the Heating Mode. The Heat Pump
uses the indoor coil as an condenser and the outdoor coil as an evaporator in the
Heating Mode. The reversing valve is energized or de-energized based on the manufacturers
specification to direct the flow of refrigerant to the appropriate coils. Whenever
the outdoor coil, or evaporator section in the Heating Mode, detects ice formed
on the coil, blockage of air through the coil, or senses a temperature usually around
42 degrees Fahrenheit or below - the Heat Pump will switch into Defrost Mode every
30, 60, or 90 minutes based on the settings on the Defrost Board. In the Defrost
Mode - the Geothermal Unit will reverse cycle which will allow hot gas to enter
the outdoor coil and defrost the coil. This will also make the indoor coil become
cold and in turn to offset this temperature - the electric heat strips or auxiliary
heat will come on. Also, the outdoor fan motor will stop during the Defrost Mode.
Operation of a GeoThermal Unit in Heating Mode
Geothermal systems can utilize many different types of loops. They are defined as
closed-loop or open-loop. Closed loops are loops that circulate water in closed
and pressurized piping. These loops can be laid horizontally or vertically. These
loops can also exist in ponds or other water sources. Open loop systems are loops
that circulate water in open and nonpressurized piping. The most utilized technique
of open loop systems is a loop that pumps from and back into a well. Both systems
utilize water pump flow centers, but each one respectively are made differently
than the other.
The following are pictures of different style loops: