GENERAL QUESTIONS
Q: How efficient is a GSHP?
A: The GSHP is one of the most efficient residential heating and
cooling systems available today, with heating efficiencies 50
to 70% higher than other heating systems and cooling efficiencies
20 to 40% higher than available air conditioners. That directly
translates into savings for you on your utility bills.
Q: Can one system provide both space heating and cooling
for my home? And what about heating hot water?
A: Yes. A GSHP can be a combination heating/cooling and hot water
heating system. You can change from one mode to another with a
simple flick on your indoor thermostat. Using a desuperheater,
some GSHPs can save you up to 50% on your water-heating bill by
preheating tank water.
Q: How does a GSHP system heat water for my home?
A: Using what is called a desuperheater, GSHPs turn waste heat
to the task of heating hot water. During the summer, when the
system is in cooling mode, your hot water is produced free as
a byproduct of the thermal process. In winter, with the heating
mode, the desuperheater heats a portion of your hot water. Desuperheaters
are standard on some units, optional on others. Stand-alone systems
that will heat water all year around can be purchased.
Q: How much space does a GSHP unit require?
A: Most of a GSHP installation is underground. Inside the house,
the heat pump units are about the same size as a traditional heating
and cooling unit.
Q: How long will my GSHP system last?
A: GSHPs are durable and highly reliable. The GSHP contains fewer
mechanical components, and all components are either buried in
the ground or located inside the home, which protects them from
outside conditions. The underground pipe carries up to a 50-year
warranty.
Q: How noisy is the GSHP unit?
A: GSHPs are very quiet, providing a pleasant environment inside
& outside of the home. GSHPs have no noisy fan units to disturb
outdoor activities, on or near the patio.
Q: How safe are GSHPs?
A: GSHP systems are safe and protected. With no exposed equipment
outdoors, children or pets cannot injure themselves or damage
exterior units. GSHPs have no open flame, flammable fuel or potentially
dangerous fuel storage tanks.
Q: What about comfort?
A: A GSHP system moves warm air (90-105(F) throughout your home
or business via standard ductwork. An even comfort level is created
because the warm air is moved in slightly higher volumes and saturates
the building with warmth more evenly. This helps even out hot
or colds spots and eliminates the cold air blasts common with
fossil fuel furnaces.
Q: How effective is this underground system?
A: The buried pipe, or ground loop, is the most recent technical
advancement in heat pump technology. Recently, new heat pump designs
and improved buried pipe materials have been combined to make
GSHP systems the most efficient heating and cooling systems available.
Q: Are GSHP systems guaranteed?
A: Nearly all GSHP system manufacturers offer a warranty for major
components that is equivalent to the warranties for conventional
heating and cooling systems. Manufacturers of plastic pipe used
for ground loops warrant their products for 50 years.
Q: Can these systems be used for commercial, industrial,
or apartment requirements?
A: Yes! Many GSHP systems are being installed using a multitude
of systems hooked up to an array of buried vertical or horizontal
loops. This simplifies zone control and internal load balancing.
Q: What are the advantages to an HVAC dealer?
A: GSHP systems create a huge retrofit market not subject to wild
fluctuations in housing construction. There is also ample opportunity
for stable growth benefiting the dealer and his employees. In
addition, these systems are relatively maintenance-free, requiring
only regular filter changes. This means fewer maintenance and
support calls. There is no outside equipment, so wear and tear
is less.
SAVINGS / COST QUESTIONS
Q: How will I save money with a GSHP?
A: GSHPs save money, both in operating costs and maintenance costs.
Investments can be recouped in as little as three years. There
is a positive cash flow, since the energy savings usually exceeds
payment on the system.
Q: How much does a GSHP cost?
A: The initial investment for a GSHP system is greater than that
of a conventional system. However, when you consider the operating
costs of a geothermal heating, cooling, and water heating system,
energy savings quickly offset the initial difference in purchase
price.
Q: What other costs are there besides the GSHP system?
A: You can expect an installation charge for any electrical work,
ductwork, water hook-up, and other provisions or adaptations to
your home that are required. Your installer can estimate these
costs in advance.
Q: How would increased use of GSHP systems affect
electricity cost and availability?
A: The reduced peak load requirements would allow utilities to
serve more customers and to lower fixed costs per customer, thus
offsetting some increased variable costs. This would result in
less cost per kilowatt, since fixed investment for new capacity
is high.
ENVIRONMENT /CLIMATE
QUESTIONS
Q: How do GSHPs protect the environment?
A: GSHP systems conserve natural resources by providing climate
control very efficiently-thus also lowering emissions. GSHPs also
minimize ozone layer destruction by using factory-sealed refrigeration
systems, which will seldom or never have to be recharged.
Q: What are the environmental benefits of GSHP systems?
A: Currently installed systems are making a huge difference in
our environment! The systems are eliminating more than three million
tons of carbon dioxide and is equivalent of taking 650,000 of
the road. GSHP systems conserve energy and, because they move
heat that already exists rather than burning something to create
heat, they reduce the amount of toxic emissions in the atmosphere.
They use renewable energy from the sun, and because the system
doesn't rely on outside air, it keeps the air inside of buildings
cleaner and free from pollens, outdoor pollutants, mold spores,
and other allergens.
Q: Do soil freezing conditions create any problems?
A: Not if a system is properly designed and installed. The three
to four foot depths allow the sun to melt the frozen soil during
the summer. Adequate length per ton capacity prevents objectionable
soil movement.
Q: Does this mean that in extremely cold climates
additional heat sources are necessary?
A: All systems require an emergency back up. Heat pumps can provide
all the heat necessary even in the coldest weather. An economic
analysis by your contractor should dictate what portion of the
heat should be provided by the heat pump and what portion by auxiliary
means.
INSTALLATION QUESTIONS:
Q: Are GSHP systems difficult to install?
A: Most units are easy to install, especially when they are replacing
another forced-air system. This is known as a retrofit. GSHPs
can be installed in areas unsuitable for fossil fuel furnaces
because there is no combustion and thus no need to vent exhaust
fumes. Ductwork must be installed in homes without an existing
air distribution system. Your dealer or installer can assess the
cost of installing ductwork.
Q: Can I install a ground source heat exchanger myself?
A: It's not recommended. Thermal fusion of the pipe, drilling
and trenching are procedures best handled by licensed professionals.
Nonprofessional installations may result in less than optimum
performance, which could cancel out anticipated savings
Q: How far apart are trenches and vertical boreholes
spaced?
A: Trenches are spaced four to five feet apart while boreholes
are spaced ten to fifteen feet apart.
Q: How long does it take to install a horizontal system?
A: This depends on soil conditions, length and depth of pipe,
and equipment required. A typical installation can be completed
in one or two days.
Q: How long does it take to install a vertical system?
A: With the vertical installation, time varies with conditions
on the site such as type and depth of the overburden, type and
hardness of the bedrock, and the presence of aquifers. Typical
drilling times are one or two days; total installation can usually
be accomplished in two days.
Q: What are the advantages and disadvantages of the
horizontal and vertical installations, respectively?
A: Horizontal installations are simpler, requiring lower-cost
equipment. However, they require longer lengths of pipe due to
seasonal variations in soil temperature and moisture content.
Since a horizontal heat exchanger is laid out in trenches, a larger
area is usually required than for a vertical system. Where land
is limited, vertical installations or a compact SlinkyTM horizontal
installation can be ideal. If regional soil conditions include
extensive hard rock, a vertical installation may be the only available
choice. Vertical installations tend to be more expensive due to
the increased cost of drilling versus trenching, but since the
heat exchanger is buried deeper than with a horizontal system,
vertical systems are usually more efficient and can get by with
less total pipe. Your GSHP contractor will be able to help you
decide which configuration best meets your specific needs.
Q: How can I be sure the pipe is installed properly?
A: Use a reputable contractor. Don't be afraid to ask for and
use references. Reputable dealers and loop installers will be
happy to give names and phone numbers for you to call and confirm
their capabilities. Find out where the installer received training,
whether he or she is IGSHPA-accredited, and how many systems he
or she has installed.
Q: Is it advisable to install a GSHP system large
enough to handle my total heating needs?
A: GSHP systems are generally sized to meet all your cooling needs.
Depending on heating needs, a GSHP system usually supplies 80-100
percent of your design heating load. Sizing the system to handle
your entire heating needs may result in slightly lower heating
costs, but the savings may not offset the added total of the larger
system. Special consideration should be given to systems in the
north where multiple capacity units should be considered to handle
the large variation between heating and cooling loads. Your dealer/installer
should provide a heating and cooling load calculation to guide
your equipment selection.
