Frequently Asked Questions
What makes a Geothermal system different from ordinary systems?
What are the components of a Geothermal system?
How efficient is a Geothermal system?
Is the efficiency rating actual or just a manufacturer's average?
What does Geothermal mean for the environment?
Are all geothermal heat pumps alike?
Does a Geothermal system heat and cool?
Can a Geothermal system also heat water?
Do I need separate earth loops for heating and cooling?
Does the underground pipe system really work?
What types of loops are available?
What is an open loop system?
What is a closed loop system?
How long will the loop pipe last?
How do I know if the dealer and loop installers are qualified?
Can a Geothermal heat pump be added to my fossil fuel furnace?
Is a geothermal heat pump difficult to install?
I have ductwork, but will it work with this system?
Do I need to increase the size of my electric service?
What is the BTU size of the furnace that's being proposed?
Should I buy a Geothermal heat pump large enough to heat with no supplemental heat?
How long is the payback period for a Geothermal system?
Will an earth loop affect my lawn or landscape?
How are the pipe sections of the loop joined?
If the loop falls below freezing, will it hurt the system?
What makes a Geothermal system different from ordinary systems?
Unlike ordinary systems, Geothermal systems do not 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, electric power is used only to operate the unit's fan, compressor and pump.
What are the components of a Geothermal system?
The three main parts consist of the heat-pump unit, the liquid heat-exchange medium, and the air-delivery system.
How efficient is a Geothermal system?
A Geothermal system is three to four times more efficient than the most efficient ordinary system. Because geothermal systems do not burn fossil fuels to make heat, they provide three to four units of energy for every one unit used to power the system.
Is the efficiency rating actual or just a manufacturer's average?
All heating and cooling systems have a rated efficiency from a U.S. governmental agency. Fossil fuel furnaces have a percentage efficiency rating. Natural gas, propane and fuel oil furnaces have efficiency ratings based on laboratory conditions. To get an accurate installed efficiency rating, factors such as flue gas heat losses and cycling losses caused by over-sizing, blower fan electrical usage, etc., must be included.
Geothermal heat pumps, as well as all other types of heat pumps, have efficiencies rated according to their coefficient of performance or COP. It's a scientific way of determining how much energy the system provides versus how much it uses. Most geothermal heat pump systems have COP's of 3-5. That means for every one unit of energy used to power the system, 3-5 units are supplied as heat. Where a fossil fuel furnace may be 78-95 percent efficient, a geothermal heat pump is about 400 percent efficient. Some geothermal heat pump manufacturers and electric utilities use computers to accurately determine the operating efficiency of a system for your home or building.
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 global warming, acid rain and other environmental hazards. UMR Geothermal provides earth-loop antifreeze which will not harm the environment in the unlikely event of a leak. The newer geothermal heat pumps use R-410A, a performance-enhancing refrigerant that will not harm the earth's ozone layer.
Are all geothermal heat pumps alike?
No. 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 degrees 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 allow the coil to be added to a forced-air furnace and utilize the existing blower.
Does a Geothermal system heat and cool?
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 flick 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 a Geothermal system also heat water?
Yes. An option called a desuperheater can be added to most heat pumps. It will provide significant savings by heating water before it enters your hot water heater.
Do I need separate earth loops for heating and cooling?
No. The same loop works for both. To switch heating to cooling, or vice versa, the flow of heat is simply reversed.
Does the underground pipe system really work?
The buried pipe, or earth loop, was an important technical advancement in heat pump technology. The idea of burying pipe in the ground to gather heat energy originated in the 1940s. New heat pump designs and more durable pipe materials have been combined to make geothermal heat pumps the most efficient heating and cooling systems available.
What types of loops are available?
There are two main types: open and closed.
What is an open loop system?
An open loop system uses groundwater from an ordinary well as a heat source. The groundwater is pumped into the heat pump unit where heat is extracted and the water is disposed of in an environmentally safe manner. Because groundwater is a relatively constant temperature year-round, wells are an excellent heat source.
What is a closed loop system?
A closed loop system uses a continuous loop of buried polyethylene pipe. The pipe is connected to the indoor heat pump to form a sealed, underground loop through which an environmentally friendly antifreeze-and-water solution is circulated. A closed loop system constantly re-circulates its heat-transferring solution in pressurized pipe, unlike an open loop system that consumes water from a well. Most closed loops are drilled vertically in areas adjacent to the building.
How long will the loop pipe last?
Closed loop systems should be installed using only high-density polyethylene pipe. Properly installed, there pipes will last for many decades. They are inert to chemicals normally found in soil and have good heat conducting properties. PVC pipe should never be used.
How do I know if the dealer and loop installers are qualified?
Don't be afraid to ask for references from dealers. A reputable dealer or loop installer won't hesitate to give you names and numbers to call to confirm his capabilities.
Can a Geothermal heat pump be added to my fossil fuel furnace?
Split systems easily can 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?
Most units are easy to install, particularly when they replace another forced-air system. They 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. 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 this system?
In all probability, yes you do. UMR Geothermal will be able to determine ductwork requirements and any minor modifications if needed.
Do I need to increase the size of my electric service?
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. Your electric utility or contractor can determine your service needs.
What is the BTU size of the 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 hat 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 fossil fuel furnaces are substantially oversized for heating requirements, resulting in increased operation 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 design 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.
How long is the payback period for a Geothermal system?
To figure this accurately, you must know how much you'll save each year in energy costs with a geothermal system as well as the price difference between it and an ordinary heating system and central air conditioner.
As an example: If you'll save $700 per year with a geothermal system and the price difference is $2,000, your payback will be less than three years. If you install a geothermal system in a new home, the monthly savings in operating costs generally will offset the additional monthly cost in the mortgage, resulting in an immediate positive cash flow.
Will an earth loop affect my lawn or landscape?
The actual process of installing the loop will disrupt the surface to some degree. With proper restoration, most loop fields are "invisible" after a couple months. After the initial installation, the loop will have no adverse effect on grass, trees, or shrubs. Nor will roots from trees cause a problem with the pipe.
How are the pipe sections of the loop joined?
Pipe sections are joined by thermal fusion which involves heating the pipe and fitting, then connecting them to form a joint that's stronger than the original pipe. This technique creates a secure connection to protect from leakage and contamination.
If the loop falls below freezing, will it hurt the system?
No. The antifreeze solution in the loop will keep it from freezing down to approximately 10 degrees F. Environmentally-safe propylene glycol antifreeze is recommended.
