WHAT MAKES A GEOTHERMAL SYSTEM DIFFERENT FROM AN ORDINARY SYSTEMS?
Unlike conventional systems, geothermal systems don’t burn fossil fuel to generate heat; they simply transfer heat to and from the earth to provide a more efficient, affordable and environmentally friendly method of heating and cooling. Typically, only a small amount of electricity is used to operate the unit’s fan, compressor and pump.
WHAT ARE THE COMPONENTS OF A GEOTHERMAL SYSTEM?
The three main parts consist of the geothermal unit, the underground piping system (open or closed loop), and the ductwork.
HOW MUCH MORE EFFICIENT IS A GEOTHERMAL SYSTEM?
A geothermal system is over five times more efficient in heating and more than twice as efficient in cooling as the most efficient ordinary system. Because geothermal systems move existing heat rather than creating it through combustion, they provide four to five units of energy for every one unit used to power the system.
HOW IS EFFICIENCY RATED FOR GEOTHERMAL?
All heating and cooling systems have a rated efficiency from a U.S. governmental agency. Fossil fuel furnaces use AFUE. Air conditioners use SEER while heat pumps use HSPF and SEER.
Geothermal heat pumps rate heating efficiencies according to their coefficient of performance or COP. It’s a scientific way of determining how much energy the system produces versus how much it uses. Most geothermal heat pump systems have COPs of 3-4.5. The WaterFurnace 7 Series 700A11 holds some of the highest recorded certified performances of 6.0 COP in an open loop and 5.3 in a closed loop. That means for every dollar of energy used to power the system, $6 or $5.30 of energy are supplied as heat. Where a fossil fuel furnace may be 78-98% efficient, a geothermal heat pump is over 500% efficient.
For cooling, geothermal units are rated by Energy Efficiency Ratio (EER). EER is a measure of efficiency in the cooling mode when measured at a constant temperature(95°F). The higher the EER, the more efficient the unit. The WaterFurnace 7 Series holds the highest recorded certified performance of 41EER for closed loop and 53.2 for open loop.
HOW EASY ARE GEOTHERMAL SYSTEMS TO MAINTAIN?
Geothermal systems are practically maintenance free. The buried loop will last for generations. The unit’s fan, compressor and pump is housed indoors, protected from the weather and contamination. Usually, periodic checks and filter changes are the only required maintenance.
When geothermal systems are offered with an outdoor geothermal unit for jobs where space is limited, its rugged housing is sealed so that no components are exposed to the elements.
WHAT DOES GEOTHERMAL MEAN FOR THE ENVIRONMENT?
Geothermal systems work with nature, not against it. They emit no greenhouse gases – which have been linked to pollution, acid rain and other environmental hazards. WaterFurnace’s earth-loop antifreeze will not harm the environment in the unlikely event of a leak. And all of the current WaterFurnace product lines use R-410A or R134a, both of which are performance-enhancing refrigerants that will not harm the earth’s ozone layer.
WHAT ARE THE DIFFERENT TYPES OF GEOTHERMAL HEAT PUMPS?
There are different kinds of geothermal heat pumps designed for specific applications. Many geothermal heat pumps, for example, are intended for use only with higher temperature ground water encountered in open-loop systems. Others will operate at entering water temperatures as low as 25°F, which are possible in closed- loop systems. Most geothermal heat pumps provide summer air conditioning, but a few brands are designed only for winter heating. Geothermal heat pumps also can differ in the way they are designed. Self-contained units combine the blower, compressor, heat exchanger and coil in a single cabinet. Split systems (such as the WaterFurnace Envision Series Split) allow the coil to be added to a forced-air furnace and utilize the existing blower.
HOW DOES A GEOTHERMAL HEAT PUMP WORK?
Heat pumps don’t create heat. They take existing heat and move it. Anyone with a refrigerator has witnessed the operation of a heat pump. Refrigerators collect heat from the unit’s interior and move it to the exterior for cooling purposes. Unlike a refrigerator, a heat pump can reverse itself. An air-source heat pump, for example, can extract heat from outdoor air and pump it indoors for heating purposes.
A geothermal heat pump works the same way, except that its heat source is the warmth of the earth. The process of elevating
low-temperature heat to over 100°F and transferring it indoors involves a cycle of evaporation, compression, condensation and expansion. A refrigerant is used as the heat-transfer medium which circulates within the heat pump. The cycle starts as the cold, liquid refrigerant passes through a heat exchanger (evaporator) and absorbs heat from the low-temperature source (fluid from the ground loop). The refrigerant evaporates into a gas as heat is absorbed.
The gaseous refrigerant then passes through a compressor where the refrigerant is pressurized, raising its temperature to more than 180°F. The hot gas then circulates through a refrigerant-to-air heat exchanger where heat is removed and pumped into the building at about 100°F. When it loses the heat, the refrigerant changes back to a liquid. The liquid is cooled as it passes through an expansion valve and begins the process again. To work as an air conditioner, the system’s flow is reversed.
CAN I USE A GEOTHERMAL SYSTEM FOR BOTH HEATING AND COOLING?
One thing that makes a geothermal heat pump so versatile is its ability to be a heating and cooling system in one. With a simple flip of a switch on your indoor thermostat, you can change from one mode to another. In the cooling mode, a geothermal heat pump takes heat from indoors and transfers it to the cooler earth through either groundwater or an underground earth loop system. In the heating mode, the process is reversed.
CAN I USE A GEOTHERMAL SYSTEM TO PROVIDE HOT WATER?
Yes. Some geothermal heat pumps can provide all of your hot water needs at the same high efficiencies as the heating/cooling cycles. An option called a hot water assist can be added to most heat pumps. It will provide significant savings by heating water before it enters your hot water tank.
CAN A GEOTHERMAL HEAT PUMP BE ADDED TO MY EXSITING FURNACE?
Split systems can easily be added to existing furnaces for those wishing to have a dual-fuel heating system. Dual-fuel systems use the heat pump as the main heating source and a fossil fuel furnace as a supplement in extremely cold weather if additional heat is needed.
IS A GEOTHERMAL HEAT PUMP DIFFICULT TO INSTALL?
Geothermal heat pump installation, if completed by a specialist, is quick and easy for the homeowner. It can be installed in areas unsuitable for fossil fuel furnaces because there is no combustion, thus no need to vent exhaust gases. Ductwork must be installed in homes that don’t have an existing air distribution system. The difficulty of installing ductwork will vary and should be assessed by a contractor, contact RB Heating for details. Another popular way to use geothermal technology is with in-floor radiant heating, in which hot water circulating through pipes under the floor heats the room.
I HAVE DUCTWORK, BUT WILL IT WORK WITH A GEOTHERMAL SYSTEM?
In all probability, yes. Contact us and we can determine if your ductwork requires any minor modifications.
IF A HOME HAS CEILING CABLE HEAT OR BASEBOARD HEAT, DO AIR DUCTS NEED TO BE INSTALLED?
Not always. It may be desirable to install geothermal heat pump room units. For some small homes, a one-room unit would handle the heating and cooling needs. Ceiling cable or baseboard units could be used for supplemental heat if desired.
DO I NEED TO INCREASE THE SIZE OF MY HYDRO SUPPLY TO USE GEOTHERMAL?
Geothermal heat pumps don’t use large amounts of resistance heat so your existing service may be adequate. Generally, a 200-amp service will have enough capacity, and smaller amp services may be large enough in some cases. We can determine your service needs.
WHAT IS THE BTU SIZE OF THE GEOTHERMAL FURNACE THAT’S BEING PROPOSED?
Furnaces are designed to provide specific amounts of heat energy per hour. The term “BTUH” refers to how much heat can be produced by the unit in an hour. Before you can determine what size furnace you’ll need, you must have a heat loss/heat gain calculation done on the structure. From that, an accurate determination can be made of the size of the system you’ll need. Most older oil, gas and electric furnaces are substantially oversized for heating requirements, resulting in increased operating cost and unpleasant temperature swings.
SHOULD I BUY A GEOTHERMAL HEAT PUMP LARGE ENOUGH TO HEAT WITH NO SUPPLEMENTAL HEAT?
Geothermal heat pumps typically are sized to meet your cooling requirements. Depending on your heating needs, a geothermal heat pump will supply 80-100 percent of your heating load. Sizing the heat pump to handle your entire heating needs may result in slightly lower heating costs, but the savings may not offset the added cost of the larger heat pump unit and larger loop installation. Also, an oversized unit can cause dehumidification problems in the cooling mode, resulting in a loss of summer comfort. We can provide a heating and cooling load calculation (heat loss, heat gain) to guide your equipment selection.
HOW LONG IS THE PAYBACK PERIOD FOR A GEOTHERMAL SYSTEM?
Geothermal systems are so energy-efficient that the payback period is remarkably brief. A study by the Air Force Institute of Technology calculated that it takes on average just seven to eight years to recoup costs.
Your specific payback point depends on factors like local utility rates, excavation/drilling costs, how well your house is insulated, the efficiency of the model you choose, and what incentives the province of Ontario or local utilities are providing at the time you install the system.
One of the best aspects about geothermal is cash flow. If you install a geothermal system, the monthly savings in operating costs generally offset the additional monthly financing cost, resulting in an immediate positive cash flow – especially in a new home. If you are considering geothermal heating and cooling why not contact us for a Free Estimate.