Geothermal Frequently Asked Questions

What does it cost to install ?

Geothermal, like other central heating and/or cooling systems can be installed in a number of configurations including forced air, hydronic baseboard, and radiant floors for distribution. The source can be either an open or closed loop. A geothermal system usually cost somewhat more than a conventional fossil fuel system with air conditioning to install but has a lower operation cost and no fuel deliveries. There are also no atmospheric emissions of carbon monoxide, carbon dioxide, and hydrocarbons with a geothermal system. For a “ballpark” estimate as to what your investment in geothermal energy might be fill out the questionaire on the contact us page.

How does the cost of heating with a geothermal system compare to other heating modes ?

Geothermal systems cost less to operate than electric, electric heat pumps, oil, kerosene, natural and propane gas.

How much will it save ?

This would depend on your local utility rates for electricity and each of the fossil fuels. Somewhere from 20 to 60% in Dollars. Ask our previous customers what their long term savings were. In ecological terms the savings are even greater!

Should I use vertical, horizontal, or open loop ?

In the Northeast only vertical systems should be used. There is much more heat available in 50°F earth than the 32°F (or less) form a horizontal system in frost and frozen earth or an iced over lake or pond.

Can snow melt be done ?

Yes, with the right equipment and the right design.

Can I heat my pool ?

Yes, for an indoor, enclosed pool. For an outdoor pool a solar pool heater is a better option.

Are there any substantial improvements in efficiency on the horizon ?

Manufacturers are continuously working to improve their products. We have seen improvements since 1975 when we first came into the geothermal market.

I am planning a large home. Should I use one large of two smaller units ?

This would depend on the layout of the home and your personal preferences as to temperature control. We have designed and installed in homes from 800 to over 15,000 sq.ft.

Is a system using antifreeze a potential environmental problem ?

This is a concern in closed loop systems. In open loop VSWC systems well water is used and this is not an issue.

I have heard of a system where air is circulated through large diameter pipes buried in the soil and then supplied to the building for heating purposes. Is that possible ?

In the Northeast this isn’t practical as the large diameter pipes would have to be buried below the 15 ft. level to get below the effect of the frost.

I am an engineer, where can I find more detailed information for commercial applications?

We have worked together with both engineers and architects in designing and installing commercial geothermal systems since 1975. We want this Simple Science to be public knowledge.

I have oil or gas hot water heat. Can I convert to geothermal?

Converting a home or building with hot water heat is not as easy.

Fossil fuel systems for hydronic (warm water) heating include either copper & aluminum hot water baseboards, cast iron radiators, or radiant heat. All of them are designed to operate at from 180 – 200 °F.

Geothermal systems, though much more efficient operate at between 100 – 120 °F, and are not compatible with distribution systems originally designed for much higher temperatures. You would need almost 3 times the size radiators, baseboards, or length of radiant tubing.

Converting a home or building basically means starting from scratch.

The up side is that you get a system that is much more efficient, has a lower heating cost, and can have zoned heating and central air conditioning as well.

I have heard radiant heat is the most efficient. What’s the story?

There should be no hidden secrets or mysteries about heating and / or cooling systems.

All heating systems are composed of 3 equally important components as follows:

  1. fuel source – oil, gas, wood, geothermal – all but the geothermal convert a fuel by burning it into heat energy.
  2. heat conversion unit – the furnace, boiler, wood stove, or geothermal unit – The first 3 take 95 – 100% of their energy from the fuel. Geothermal gets 70 – 75% of it’s energy from the earth, and the other 25 – 30% from electrical energy for conversion.
  3. Distribution – radiant, hydronics, or forced air – everyone is familiar with all of these. Forced air is the only one that can also do zoned central air conditioning.

All 3 of the components of a heating system are just as important. Only if all 3 are correctly designed, installed, and maintained will you get the comfort and economy you deserve, and have paid for.

Some information on radiant heat. We are certified on and do install Wirsbo radiant heat for the right applications but, it is not more efficient than other forms of heat. You are still trying to transfer heat through a poly-plastic, which is never efficient.

The right applications for radiant heat are those where a floor’s temperature is the most critical thing, such as:

  1. truck repair garages, where people have to work on their backs on or just above the floor
  2. fire departments and rescue squads where the rolling stock must be kept above freezing
  3. basements floors that have no carpeting

Radiant heat is just what it says. The heat must radiate from the floor, not allowing convective currents to be set up in the space above it. Any energy cost savings is from the idea that only the floor and the 6 to 7 ft. above it are heated, and not any cathedral space above it. If convective currents are set up by the installation of air conditioning or heat recovery ducts, the introduction of a whole house ventilator, or any method that breaks this “stagnant” radiant pattern there is no energy cost savings.

Some wrong applications for radiant heat are:

  1. any space above another conditioned space
  2. any basement where you will have carpeting on the floor
  3. any cathedral room with whole house ventilation, air conditioning,or a fresh air system

Radiant heat systems in themselves are not more efficient than any other form or heat distribution. In fact they are less efficient than forced warm air and hydronic warm water heat through copper tubing.

I am on a municipal water system. Can I convert to geothermal energy?

Water is the heat transfer fluid, not the heat source. The earth is the heat source and any water must be coming up from at least 15 ft. down to not be affected by the frost. A pond, lake, or stream on or near your home or building is not a geothermal source. You would have to drill a well or install a well point if you have a high water table.

I have steam, cast iron radiators. Can they be converted to operate on geothermal?

No, steam systems operate from 220 + °F and geothermal systems, though much more efficient cannot deliver within 100°F of this temperature. Steam systems were designed when buildings had little or no insulation, and fuel was relatively cheap.

I have a lake, pond, stream, or body of water adjacent to my home. Can I use this as a geothermal source?

No, again, the water is not the fuel source, only the heat transfer medium. The water must be underground fed from at least 15 ft. down.

I have a 1 acre lot next to my home. Can I do a horizontal loop?

No, we have frost that goes down from 4 – 6 ft. and it’s cooling effect goes down 15 ft. To get into the geothermal “temperate zone” we need to have our source at least 15 ft. down

I have an old building or home and have heard that the HIVAC systems take up a lot less space for air ducts.

They do take up less space but at a large premium. With the high velocities and large differential temperatures they are not as efficient due to increased pressure required by high static pressure blowers. They also require frequent maintenance as the extra high differential temperatures tend to have the air conditioning coils “ice up” easily and must go through constant defrost cycles. Ask anyone who has had one for any number of years.

We have a vacation home in the Mountains. Is it feasible to use geothermal there?

If this home is for Summer only use, or you close it down, shut off any heat, and drain the pipes in Winter, no.

I/We have a very deep drilled water well but it has very low production. Can we use this well for geothermal?

Very deep water wells, in the 400 ft.+ depth can usually be used for geothermal purposes, even though some of them don’t produce enough water for domestic use. If the well produces enough “drawdown” for both purposes great but, a 500 ft. “dry hole” can still be a “permanent fuel tank” for you and your family, even if it cannot give you drinking water.

My friend bought a home with a horizontal closed loop and says it works great until the end of the Winter when it seems to “run out of fuel”, why?

Geothermal loop systems are region specific. In the North we can’t bury a pipe at 3 to 4 ft. and expect to get heat from it the whole Winter long. Some time during the winter the loop will freeze and as everyone knows ice makes a great insulator, ask any Eskimo. In fact, the earth’s temperature below the frost will be lower as deep as 15 ft. below the surface. The larger the frozen layer of ice around the loop the harder it is to eke out any heat at all from that loop. This is after the loop has already dropped to 32°F. With a vertical standing water column (VSWC) supply you never run out of fuel due to you loop freezing up. The earth is always 50°F, and so your supply to the geothermal equipment is a constant, January through July. Also, when you use well water as your heat exchange fluid there are no environmental questions about what anti-freeze to use.

I’ve heard geothermal systems blow cold air in Winter?

Your Grandfather’s old fossil fuel oil or gas furnace heated the air that passed through it somewhere between 60 and 100°F every pass of air. It literally “fried” the moisture out of it. It also delivered this air with curtain shaking, cat chasing high velocities. With it’s 1.5 to 2 air changes per hour you were either too cold or too hot, with very uneven temperatures throughout the house. Geothermal systems are designed to stringent ACCA standards for 4 air changes per hour and only 20 – 25°F temperature rise every pass of air. With higher volume, lower velocities (cat friendly) you are comfortable, and don’t know how you got there. So, geothermal systems deliver warm air, not hot air. If the room temperature is 70°F the average delivered air temperature should be 90 – 95°F. The bottom line is it will heat your home for a lot less than any other automatic method. Of course free wood can do it for less, and wood is also renewable.

How efficient is the air conditioning side of a geothermal system?

About twice as efficient as a conventional central air system. Think, how hard is it to cool a home or building with 50°F water being used as the cooling medium, not 90 -100°F air. That means that when you have a 3 ton system it’s always a 3 ton system, even at 110°F outside. Conventional systems are rated at 85°F outdoor air and system capacity drops off with temperature rises above that mark. Geothermal systems have a constant 50°F “condenser”, so it is always the most efficient with 100% of it’s capacity.

Why don’t you recommend or install closed loops?

We did, in the early days, many years ago. Then, we started collecting data and discovering that in the Northeast we have some advantages that other parts of the country do not have. We have relatively clean water, and high density bedrock with excellent heat transfer characteristics. Later on ARI started testing, and still does, any geothermal brand sent to them for 3rd party verification of performance standards.

What ARI also proved is that any equipment in the Northeast that can operate on direct contact well water (VSWC) will have a 25 – 30% higher performance and lower operating energy use as the same piece of equipment on a closed loop (click here to view ARI Standards)

I have heard that “on demand” water heaters are much more efficient than conventional types?

We installed in a few gas and electric “on demand” water heaters over a decade ago. Had to take out all of them, within two years.

If you are heating distilled water in a lab environment they work fine but, if there are any minerals in the water at all, especially calcium and iron, they will plug up fast and have to be acid cleaned at least every 6 months.

Rather than heating water to remain in storage they heat it very rapidly in section of copper less than 8 ft. long, wrapped around the gas heat exchanger. The electric units use solid state TRIAC output switches that operate very hot. The water has to be heated from ground temperature of 50°F to at least 120°F, which is a rise of 70°F in less than 8 ft. of copper. This fast heating boils off any dissolved air in the water and plates out any and all minerals dissolved in the water on the inside of the copper. Over time (sometimes as little as months) the plating of these minerals decreases the efficiency of heat transfer from the hot flue gasses to the water and as a result the discharge flue gas temperature rises, wasting energy that was meant to heat the water.

Once this plating of minerals occurs the only way to remove it is with a solution of acid pumped through the heat exchanger from a clean bucket, with a specially designed acid pump every few months. Over time this constant “scouring” of the copper with the acid cleaning eats through the heat exchanger and your “on demand” water heater is now scrap metal.

Ask anyone who has had one of these “on demand” units over a year and get their feedback. I have heard of a few cases where they do operate, but they were in the “lab” condition I mentioned for heating distilled (demineralized) water.

We don’t have a drilled well but water our lawn with a point or dug well?

The key here is that the source of the water is coming up from at least 15 ft. below the earth surface. The water is not the heat source, only the heat transfer medium. We have many systems operating on well points, some on dug wells and one on a flowing stream at ground level. All have year round water temperatures from 49 – 51°F.

I own a commercial building. What advantages does geothermal have for me?

  1. Lower heating and cooling costs – since 75 – 80% of the energy for today’s ARI certified equipment comes from the earth the operating costs for both heating and cooling are extremely low.
  2. Lower demand costs – one of the largest costs for a commercial building is for the compressors in air conditioning, whether central or window units. With geothermal cooling not only is the energy cost about half that of a conventional system but, the electrical demand factor is way lower. Demand factor (Rate 2 electric service meters) is what you pay for the utility having to be ready to deliver the highest “demand” you may need in the next 11 calendar months after you have hit your “KWD peak”. For that period you will pay a premium, which in many cases can cost you even more than your KWHR use is. Check out this 130+ year old building that was converted to geothermal in the mid 1980’s.

Why do companies that design and install geothermal systems always talk about “backup” or “supplemental” heat systems? Can’t the geothermal system supply all of the heating and cooling? If not, why?

“Backup” heat is an old term from the air source heat pump era (not geothermal). The source of the heat was the outdoor air, not the earth. When the outdoor air temperature went below the economic balance point the heat pump was turned off and the “backup” heat came on to heat the home or building. In most cases this was electric strip heaters. They had to be sized to heat the entire building or home without the heat pump being operational. Hence the term, “backup”. The economic balance point was generally in the range of +30 to + 40°F. For obvious reasons these air source heat pumps were, and still are not, practical for use in the Northeast.

Commercial buildings that have air conditioning loads greater than or equal to their heating loads often do not require “supplemental” heat to a geothermal system.

In many cases, in our area the heating load is very much larger than the cooling load and it does not make economic sense to size the geothermal heating system for the lowest expected temperature for the next 50 years, knowing that a majority of that time it will be vastly oversized. The incremental cost difference on equipment will not give a reasonable return on investment.

In most residential and light commercial applications it does not make economic sense to install a geothermal heating and cooling (HVAC) system that will supply 100% of the heat.

Most Northeastern locations will only hit -40°F occasionally in some Winters, but not every Winter.

In sizing geothermal HVAC systems in this part of the country we utilize the BINS method of averaging the most current 30 years weather data, and supplying 85 – 90% of the home or buildings heat with geothermal, and 100% of the air conditioning.

This gives the best balance of ecology, economy, and common sense.

In existing homes or business which already have installed serviceable equipment it usually makes sense to utilize it as the 10 -15% supplement, knowing it should operate a fraction of the previous time. This system can be wood, coal, oil, or gas driven. If an “automatic” system is required, that lets out the wood and coal options.

I bought this geothermal unit over the internet, will you install it?

No! We only design with and install equipments that meet IGSHPA and ARI standards. That way you know what is printed on the specification sheet as far as equipment performance is the truth. If it’s not IGSHPA and ARI certified we would not know what it’s input and output requirements and what performance it will really produce for you. ARI Standards and Guidelines

Can geothermal system be incorporated into other renewable systems like solar photo-voltaic electric, wind powered electricity, hydro-electric , passive solar, and solar water heating?

Yes to all of these. Contact us for specifics.

We’re looking to build a home that has the lowest environmental impact?

So are we, lets talk.

Why would you choose geothermal instead of some other form of renewable energy?

We have installed all types of solar heating and electric systems and we still find geothermal gives you the “biggest bang for your buck”, in that it addresses the majority of most people’s home energy needs. Heating and Cooling comprise from 60 – 70% of most homes energy consumption. Today’s ARI certified and correctly applied geothermal systems should be able to get from 75 – 80% of that energy from the earth, responsibly. Most other renewable systems replace a much smaller percentage of your total energy use.

A lot of the other guys are saying closed loops are the only right way to install geothermal in the Northeast. They claim that their systems are more efficient than yours ?

See industry standards and talk to some of the 770+ customers we have designed and installed VSWC systems for over the past 40 years. ARI Standards and Guidelines

I see horizontal, pond, and lake loops in all the national magazines. Why won’t they work in the Northeast?

With today’s state-of-the-art geothermal equipment over 80% of heating and cooling energy can come from the earth, responsibly. Please look at our web site in depth, as there is over 40 years of data there, including a booklet we published in the 1980’s to regionalize ideas that were published in national magazines.

When you pick up a national or world publication for articles or ideas about sources of geothermal energy for space heating or cooling you get the whole gamut of possibilities world wide.

Then, when you think regionally some of those ideas may not work in your particular case. Examples would be as follows:

  1. Horizontal “slinky” loop in Northern USA or Canada – unless you can trench down at least 15 ft. to install many hundreds of feet of polyethylene pipe below the effect of the Northern Frost Zone you’re wasting your time to go horizontal. This works in the central plains of Canada, but not the Northeast or Northwest USA, because of our deep bedrock.
  2. Pond or Lake Loop in Northern USA or Canada – These bodies of water are FROZEN in Winter, and you’re wasting your time. This works great in the South, though.
  3. Vertical Standing Water Column (VSWC) in the Northeast – Due to our relatively clean water and high density bedrock this works best in New England and New York. It Utilizes direct contact with well water and no antifreeze is required. ARI ratings boast 25- 30% higher output performances and lower operating costs, with all energy costs included.
  4. Vertical Closed Loop Anywhere – On the East and West coasts where brackish water can be very corrosive this is a good alternative in any climate. It still has the drawback of having to deal with an antifreeze and transferring heat through a low density poly plastic pipe.
  5. VSWC or Well Water Systems in the Sun belt – this is not recommended as the colloidal red clay content in well water would plug up piping and equipment quickly. In this application, since frost only goes down inches, not feet, horizontal closed loops or slinky’s are recommended. Pond or lake loops can also be used effectively in the South.

I have a wood or coal stove. Can I incorporate it into a geothermal system?

Yes, any heat generated within the shell of the house can be used to heat the whole home, evenly. The ducts and installed low velocity fan will deliver that heat to all areas served by the system. Many of our customers do just that. They will set the geothermal thermostat for the lowest temperature they would like the home if the fire goes out, then turn the fan on distribute the wood / coal heat. During the night when the fire goes out and the house cools down the geothermal comes on to maintain the setting.

I’ve heard that closed loops come with a 50 year guarantee. Is there something similar for open loops or VSWC systems?

The 50 year guarantee is only as good as the company behind it. When the company closes or moves out of the area, never to return you’re kind of stuck. With an open loop or VSWC system it is always accessible for any required maintenance many years down the road. A good,reputable NGWA driller and / or pump man can service it any time of year. Over the past 40+ years we have seen many things that make closed loops a tremendous liability, such as:

  1. earth quakes – if you haven’t notices we have them, and a sheared closed loop puts you up the creek, with no way to repair it. Not so for the VSWC that any good NGWA certified well driller and / pump man can work on. They always know just where they are.
  2. Anti -freeze leaks – many of these 50 year guaranteed loops have leaked in a lot less than 50 years, dumping their anti-freeze into the groundwater and your aquifer. Some of these anti-freeze solutions are toxic to animals and humans. We use only well water in our systems.
  3. If 10 to 40 years from now you decide you want to put in an in ground swimming pool and your closed loop field is there, tough luck. That’s if you remember where it is, or you were the original homeowner. You have access to our VSWC well casings, from industry standard well caps, any time 24/7/365.

I have heard of a system using direct buried copper pipe in the ground and have heard it is more efficient?

Over 30 years ago we did a number of these, what came to be known as DX systems. They worked great for a few years, but all got pinholes in the copper tubing and lost all of their refrigerant charge to the earth over time. None lasted over 10 years. We thought this couldn’t happen as city water mains are copper and they are in the ground a long time without a problem so we researched it further. It seems it is a combination of the fluctuating refrigerant pressures, from a low of 40 to a high of 375 psi, as well as the Calcium in the earth in the Northeast in the form of Limestone.

This may work perfectly well in other parts of the country where they don’t have the potential or Limestone or Calcium in direct contact with the copper tubing in the ground heat exchanger.

I’ve heard of this geothermal unit with the highest EER on the market. Why won’t you use it?

When choosing geothermal equipment for a particular design application you have to know the primary goal, is it heating, cooling, or are they equal. If the primary goal is cooling, like in the South, or some commercial applications the equipments with the highest EER rating should be looked at.

Scroll and rotary compressors can develop some great EER’s for lower heat buildup and lower energy consumption while in the cooling mode. But, these same units have lower heat outputs because they do not develop the heat of compression that reciprocating compressors deliver.

If your primary concern if heating, which is most residential and light commercial applications in the Northeast we choose the reciprocating compressor models of the manufacturers product line. True, the cooling EER’s won’t be quite as high as would another model, but we get the heat of compression and heat output we are designing for.

That is the reason we might choose a different product line by the same manufacturer for a commercial vs. residential application.

Summation: We believe, and have for over 30 years, in renewable energies, and always doing the right thing for our environment. We openly invite other HVAC contractors, architects, engineers, home and building owners, etc. to join in the environmental switch to wood, wind, solar, hydro- electric, and geothermal.

Commercial 2X Energy Savings –

In commercial buildings geothermal HVAC systems produce a 2 X energy savings, first in much lower heating and cooling costs, then in drastically reduced electrical demand costs.

Ask anyone who has a commercial building and pays the utility and energy costs, you not only pay for the Kilowatt Hours you use, but also for the Kilowatt Demand you may need.

The utility monitors your electric Demand and locks in the highest Kilowatt Demand in any one floating 12 month period.

From an agreement reached with the Public Service Board or Commission they are allowed to charge you 50% of that cost for the next 11 calendar months, based on the highest peak hit in any 15 minute period.

They say it is the cost of them being ready to deliver 100% of your Kilowatt Demand at any given moment.

With conventional heating and cooling equipment many businesses pay the largest portion of their electric bill for Kilowatt Demand, not Kilowatt Hours. That’s like paying for a premium parking space that you only get to use 15 minutes all year.

With Smart -Energy technology and properly applied geothermal HVAC and Refrigeration Systems most businesses can reduce both their Kilowatt Hours and Kilowatt Demand, to far below what they thought possible.

Some good examples from our web site are:

Smith Flats – 34 years ago we converted this 15,000 sq. ft. commercial office building to geothermal energy. The electrical engineer in the design team said the existing 120 / 208 VAC / 3 phase / 400 Amp service was far too small for the required 28 Tons of Heating and Cooling for the building. He was wrong. In fact it was far to large, as in that time we haven’t even come close to half of the Kilowatt Demand he predicted.

Regan & Denny Funeral Service – Back in 1991 then owner Chris Gauthier wanted to not only make this well known landmark on Quaker Road in Queensbury, NY more energy efficient, but much more environmentally friendly. His 10,000 sq.ft. building had electric heat and conventional central air conditioning. It also had very high electrical costs, both in total kilowatt hours (KWH), and electrical demand ( KWD ), due to this type of system. At that time there was no natural gas available to the building. A single 360 ft. water well was drilled in the back parking lot of the building to serve as the geothermal systems permanent fuel tank. Three geo- thermal heating and cooling units were installed to serve the offices, chapels, meeting rooms, and casket display room. After many years of operation Chris told Harold that the net economic result of his conversion to geo- thermal “Smart-Energy” was a reduction of over 1/2 of this total KWH and over 2/3 of his KWD. This building can be seen on our web site under commercial geo- thermal economics. Natural gas has been available to the building for many years now, but there is no move to convert as geothermal is substantially more economic.

Bob Sharp – In 2003 we designed and installed geothermal HVAC for his new 6,000 sq.ft. dental office. With 6 Zones of control,11 Tons of heating and cooling load, numerous vacuum pumps, air compressors, and other dental power equipment we told Bob that all he needed was a standard residential service of 120 / 240 VAC / 1 phase / 200 Amps. Bob has never had any problems from our “undersizing ” of required service. His low operating costs are reflected in how much energy the geothermal systems save.

Stan and Chris DiStefano – highway construction general contractor. You can see both their 12,000 sq. ft. home that we designed the geo- thermal system in 2003, and their offices in the 9,000 sq. ft. building 4 years ago. Company engineer Craig Swayne gave us copies of total utilities for this building for one full year. Gas usage was $ 3800, and Electric $ 3500, for a total utilities for this 9,000 sq.ft. building of $ 7,300. That’s $ 0.81 / sq. ft. Compare that to any other commercial building you know, it will “blow their doors off”! Oh yes, their electric service for this building with 15 Tons of HVAC equipment, and all of the welders, air compressors, etc to work on multi-ton highway construction equipment is 120 / 208 VAC / 3 phase / 400 Amps. You can find the Green Island Contracting building on our web site, or call 518-271-4485.

AHRI ( formerly known as ARI) Testing –

Air Conditioning Research Institute ( ARI ) has been the independent, third party testing organization for air conditioning systems for over two decades.

Almost two decades ago many of the geothermal manufacturers also started having their equipments tested and ARI Certified.

ARI did not set any standards or limits. They just specified that they could test production run equipments randomly, and that when tested they must perform to the specifications published by the manufacturer.

That way, and only that way, could the manufacturer put the ARI label on their equipment and specification publications.

Some manufacturers, for obvious reasons, choose not to have ARI test their equipments. What you get from them is unknown, having to rely on their own honesty, and fairness in marketing, which did not work before ARI came into the geothermal industry.

Many pre ARI certification manufacturers have disappeared, as it was shown they could not live up to their own published performance claims.

When ARI tested geothermal equipments they set different test conditions for the expected operating parameters. They included all energy requirements to achieve these performance figures.

“Performance at ARI/CSA rating points – includes appropriate pumping penalty” meant the energy requirement to supply circulation of water or a heat transfer anti-freeze fluid was included in their calculations.

ARI-330 – This was the operating condition for any and all geothermal equipments operating in a closed loop mode.

ARI-325(50) – This was the operating condition for open loop or VSWC equipments operating in the Northern USA and Canada, which had average Entering Water Temperatures (EWT) of 50’F. This is what is called Open Loop / VSWC, and what we use.

ARI-325(70) – This was the operating condition for open loop or VSWC equipments operating in the Southern USA , which had average Entering Water Temperatures (EWT) of 70’F. In areas of the Southern USA where water is relatively clean this is the preferred method. But not in the clay belt, where dissolved colloidal clay can quickly plug and foul piping and heat exchangers. This is the predominant reason most geothermal systems in the South are closed loop, ARI-330.

CASE IN POINT –

For our Northeast climate we use one of these such ARI tests to make a point as to the technical reason why we prefer the open loop or VSWC over the closed loop ground supply.

The attached specification sheet is for a piece of Climate Master 1991 geothermal heating and cooling equipment. This model is the Size 60. We use this example because of the ease of reading this ARI format. Later ones were not as easy to read. Remember, these tests are done on the same piece of equipment.

ARI – 325 ( open loop or VSWC / with direct contact well water )

Heating-50 – 60,000 BTU COP 3.0
Cooling-50 – 68,000 BTU EER 12.3

ARI-330 ( closed loop / with poly-plastic pipe and anti-freeze )

Heating – 43,000 BTU COP 2.6
Cooling – 60,000 BTU EER 10.6

Canadian standards were also tested then and are also shown on the example equipment.

So, in conclusion we think it is rather obvious when faced with the technical choices of operation in the Northeast the overwhelming majority of the time the right one is the open loop or VSWC.

Why would you throw away a 25 – 30% performance advantage, and with lower operating costs !

Caution: There are still manufacturers out there who do not have their equipments performance tested by AHRI. This for obvious reasons. In the Northeast there are at least three that are currently selling a lot of equipment, and a “bill of goods” to unsuspecting contractors. Have already heard “horror stories” of the results of some of them. Don’t let some less than reputable manufacturers convince you too that “geothermal just doesn’t work in our cold climate”, or that the real success stories over the past 4 decades are a myth.

ACCA standards –

Geothermal Warm / Cool air systems are not like your Grandfather’s “drafty old hot air” system.

Almost everyone remembers the olden days with hot air fossil fuel systems like this:

  1. You felt a chill all over between cycles, when all of a sudden the big beast in the cellar came on with a roar.
  2. Next the fan came on and very hot air came whistling out of all the supplies in the floor, blowing curtains around and chasing the cat down the hall……… then you were too warm.
  3. Then the furnace shut off with a clunk or bang and the curtains settled down for a few minutes. Sometimes the cat came back out from hiding.

Isn’t that pretty much what all of us remember from the olden days of fossil fuel gas and oil furnaces and “forced hot air” systems.

These furnaces moved a little air, very fast. Any space that needed heat had to get it quickly as the fan and supply system only moved about 2 air changes per hour. In effect it would change the air in each room that had a supply register every 1/2 hour. Unfortunately, it rarely ran as much as 30 minutes unless it was below Zero outside.

So, not only did the temperature fluctuate dramatically between “heat” cycles but the differences in temperature between rooms and areas of the home or building were dramatic.

Also, since the air was heated to such a high level it tended to “fry”all of the moisture out of it. Old hot air systems were also very dry in the Winter.

We all hated that, didn’t we.

Todays state of the art geothermal warm/cool air heating and air conditioning system is the furthest thing from that old dinosaur of a fossil fuel system.

Geothermal warm/cool air systems follow stringent Air Conditioning Contractors of America (ACCA) standards, insuring even temperatures, with little variation in room temperatures and no window curtain shaking and cat chasing high velocities.

ACCA standards for geothermal systems call for 3.5 – 4 air changes per hour, ( almost twice the old standard ) delivered at low velocities. This insures even temperature deliveries with no high velocity noises.

This does require better design and installation of duct distribution systems than the old hot air beast used to have, unless the home has fairly newly designed central air distribution.

A properly designed and installed geothermal warm/cool air system will make it’s owner extremely happy. It will deliver 3.5 – 4 air changes per hour, moving the conditioned air through every space that needs it every 15 minutes. This is for heating, cooling, dehumidifying, humidifying, or air purification.

Air supplies can come out of floors or ceilings and still give even comfort, do to the 4 air changes per hour delivered to every space. The supply register that best conditions the space is the one that is chosen in every application.

Distribution follows the “donut” principle. That is, supply the perimeter and return to the middle. That way every space that needs conditioning gets the proper air flow and there are no dead air spots like the kitchen, bathroom, or hallways. This calls for a minimum of air returns toward the middle of the main floor. One is the optimum number, however sometimes due to the configuration of the home or building as many as 2 or 3 may be required.

Today’s geothermal warm/cool air systems can even be zoned to make areas with different characteristics have different control points. Good examples of these are bedrooms vs. living rooms, or the second floor of a home vs. the main floor.

It never made economic sense to over cool the first floor of a home to make the second comfortable in Summer and visa-versa for over heating the second floor to make the main floor comfortable in Winter.

We utilize Jackson Systems Zone Controls for the best balance of comfort, operating economy, and customer support. Visit them at www.jacksonsystems.com.

Since the air is not heated to a high level it is never “fried”, or dried out. Over time, as a new home or building dries out from the inherent moisture built into the construction materials it still may need humidity addition in Winter for a better comfort level. At that time central humidification can easily be added.

In some older and historic homes it is desired to maintain the period look. Though we do not install cast iron and brass floor supply registers we utilize standard sizes and you can purchase these at any future date and easily install yourself, replacing the beige stamped metal units we have installed. One good source is www.reggioregister.com. We do not, however recommend any units that restrict the air flow too much for a geothermal installation. In the past both the brass and cast iron units have worked well.

If you still don’t like “hot air systems” all we ask you to do is talk to some of our over 720 geothermal customers. Ask them how they like their warm/cool air geothermal systems. Many have had their systems over 20 years. Some are on their second home with one of our systems.

The gist of this is that you will be comfortable, Summer, and Winter, and unless you put your hand right on a supply air register you won’t feel the air move to know how you got there.

Variable Frequency Drives (VFD’s )-

These are controls on submersible well pumps to make them run as a variable speed / variable volume to match the demand at any given time.

Some manufacturers call them “constant pressure”, others call them “variable drives”, and there are other names for the same thing.

The characteristics they exhibit make them especially useful with an Open Loop / VSWC geothermal installation.

The incoming line voltage power can be either single or 3 phase as the VFD converts it to a Direct Current (DC) voltage first. Then it generates it’s own Alternating Current (AC) voltage as a variable frequency / variable voltage, using only as much as it needs to supply the pressure and flow demands on the water flow as it needs at any given time.

Pumps operating on VFD’s always start on Zero speed, and shut off on Zero speed. That way there is no inrush of current ( locked rotor ) to get the pump into motion from rest. There is also no high torque twist of the pump in the well as it comes up to speed from rest.

This allows the driller to size the pump wire for the 100% operating current of the motor, but not have to deal with the 5 – 6 times that number to satisfy the locked rotor start.

Now comes the good part:

– Just like when an incandescent light bulb on a dimmer control drops it’s watt draw with the square of drop in control voltage, so does the VFD drop it’s power consumed with the square of the drop in speed of the pump.

– for example – A pump running on a VFD that consumes 800 watts at 100% speed. That same pump running on 50% speed would only consume 25%, or 200 watts. WOW !

An average geothermal system in the Northeast would operate from 2000 – 2600 Hours for Heating and 400 – 500 hours for cooling, for an annual total of 2400 – 3100 hours.

With such dramatic pumping cost reduction, it’s obvious that VFD’s can quickly pay for themselves in pumping cost energy savings.

Heat options –

There should be no hidden secrets or mysteries about heating and / or cooling systems.

All heating systems are composed of 3 equally important components as follows:

  1. fuel source – oil, gas, wood, geothermal – all but the geothermal convert a fuel by burning it into heat energy.
  2. heat conversion unit – the furnace, boiler, wood stove, or geothermal unit – The first 3 take 95-100% of their energy from the fuel, the other 0 – 5% is electrical energy used in conversion. Geothermal gets 75 – 80% of it’s energy from the earth, and the other 20 – 25% from electrical energy for conversion.
  3. distribution – radiant, hydronics, or forced air – everyone is familiar with all of these.

Forced air is the only one that can also do zoned central air conditioning.

All 3 of the components of a heating system are just as important. Only if all 3 are correctly designed, installed, and maintained will you get the comfort and economy you deserve, and have paid for.

Some information on radiant heat. We are certified on and do install Wirsbo radiant heat for the right applications but, it is not more efficient than other forms of heat. You are still trying to transfer heat through a poly-plastic, which is never efficient.

Insulation values below the radiant tubing must be at least 3 times what is above in order to force the radiated heat up. Changing that formula in the future by the addition of insulating floor coverings renders the radiant heat ineffective. The water returning to the heat source is the same as that leaving and nothing is heated.

The right applications for radiant heat are those where a floor’s temperature is the most critical thing, such as:

  1. truck repair garages, where people have to work on their backs on or just above the floor
  2. fire departments and rescue squads where the rolling stock must be kept above freezing
  3. basements floors that have no carpeting

Radiant heat is just what it says. The heat must radiate from the floor, not allowing convective currents to be set up in the space above it. Any energy cost savings is from the idea that only the floor and the 6 to 7 ft. above it are heated, and not any cathedral space above it. If convective currents are set up by the installation of air conditioning or heat recovery ducts, the introduction of a whole house ventilator, or any method that breaks this “stagnant” radiant pattern there is no energy cost savings.

Some wrong applications for radiant heat are:

  1. any space above another conditioned space
  2. any basement where you will have carpeting on the floor
  3. any cathedral room with whole house ventilation, air conditioning,or a fresh air system

Radiant heat systems in themselves are not more efficient than any other form or heat distribution. In fact they are less efficient than forced warm air and hydronic warm water heat through copper tubing.