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The GeoExchange space conditioning system provides:

Heating Air or Heating Water Cooling Air or Chilling Water Heating Domestic or Process Water

Table 8c-1 - GeoExchange functions

A typical installation will provide 100% of the dominant heating or cooling load and approximately 50% - 65% of the domestic water heating. In all cases the successful installation will include a complete integration of all of the three major components of the GeoExchange installation.

Earth Coupling Portion Heat Pumps Building Distribution

Table 8c-2 - Major GeoExchange Components

Training programs and GeoExchange contractors that include all of these three interrelated elements insure a successful installation. A GeoExchange system lead by a organization with only a portion of the integrated knowledge is most likely to falter or fail to perform as intended.

I While the present engineering, architectural and HVAC skills are familiar with

Building Distribution and Water Source Heat pumps (Water-to-Air), there are interfaces that must be understood and addressed. Industry sponsored training programs for GeoExchange design and installation are discussed in this section.


Florida Heat Pump


Water Furnace

Table 8c-3 NYC Area Active Manufacturer Geothermal Training Programs:

International Ground Source Heat Pump Association (IGSPHA) - certified instructors , closed loop software

Geothermal Heat Pump Consortium (GHPC) -"Design Assistants", introductory videos, tools and instructors

Association of Energy Engineers (AEE) - Certified GeoExchange Designers1,

Various tools and publications

Table 8c-4 NYC Available Agency Sources of GeoExchange Trainers

There are also approximately ten other manufacturers in the U.S. producing geothermal heat pumps. Their addresses and contacts can be obtained from the Air Conditioning and Refrigeration Institute (ARI), Roselyn, Virginia. Also see Appendix E, below.

Many manufacturers have segregated geothermal from conventional water source heat pump distributors/offices. Insure your inquiry and resultant manufacturing contacts are the Geothermal side of that organization. Boiler/Cooling Tower water source heat pumps (e.g. ARI 320) are not suitable for geothermal applications in New York


As discussed above earth coupling can take several forms either direct exchange with the earth or indirect through closed loop piping, the merit of each of these methods are discussed elsewhere in the Guide (see sections xxx). Each general method requires a trade skill. These skills are provided by two major segment of the trade structure:

1_Direct Coupling Well Water, either open or standing column wells -

these are typically experienced geothermal well drillers and installers. All are licensed well drillers and possess the equipment and skills to drill deep rock wells and appropriate casing. Qualified drillers are typically member of the National Ground Water Association (NGWA)2 and have various levels of certification from that organization. Certification examinations are held at the NGWA annual meeting and at other sites throughout the year and are often jointly held with IGSPHA, see paragraph below. NGWA certifications are a trusted method to access the quality of a well drilling service. The well type earth coupling is either identical or very similar to conventional water well drilling.

2._Closed Loop Installers, vertical, horizontal or Slinky - these are a variety of trades men. All are certified by the International Ground Spruce Heat Pump Association (IGSPHA)3 and have pipe fusion certification from the primary high density pipe manufacturers. The certification program involves a three day training program, ending in a written examination. While this certification program has a dominant content of closed loop technology, the instruction outlines include well water methods and proper design techniques. IGSPHA has certified several hundred certification instructors. These instructors are from the manufacturing industry and academic resources.

Presently active well contractors in the New York City area with GeoExchange experience:


Aquifer Drilling & Testing,Queens, NY Boyd Wells, Carmel NY Connecticut Wells, Bethlehem CT Water Resources, Flushing NY William Stothoff Co, Flemington NJ

Certifications NGWA



Table 8.c-3 - GeoExchange Well Contractors, Presently Active NYC

While the majority of GeoExchange training has been directed towards the unfamiliar earth coupling methods, installation problems are most often traced to a lack of

I understanding on the integration of the three components of a GeoExchange system, earth, heat pump and distribution. An effective GeoExchange training program(s) must include all three elements.


Trade and manufacturer training programs for conventional water source heat pump systems are active and some have developed local New York GeoExchange training programs.

America Society of Refrigeration & Air Conditioning Engineers (ASHRAE)

Region 1-006 - Long Island Region I-008 - Greater NYC

Commercial geo Information & Tools - Air Conditioning Contractors Association (ACCA ) Region 1 - NYC

Residential geo information & Tools - Software Tools -

Association of Energy Engineers (AEE)

Air Conditioning and Refrigeration Institute (ARI) International Standards Product Efficiency Listings -

Table 8.c- 4 National Trade Organizations with GeoExchange Training Resources

These organizations have the structure and resources to integrate local professional training and informational seminars for GeoExchange. Integration of existing air and water design and distribution methods to the wider range geothermal heat pump technology and earth coupling technology is a formula for further success of GeoExchange in the New York City area.


A. A TYPICAL MANUFACTURER'S Outline4 - for Engineers and Contrac- ^


Geothermal Installation & Service Technician Training Agenda


Training Objectives & Overview

I. Equipment Installation Overview Installation-Operation-Maintenance (IOM) Manuals

II. Refrigeration System Diagnosis (water source equipment)

III. Specification Catalog Data Pressure Drop Calculations - Fluid Flow Verification

Heat of Extraction / Heat of Rejection Water Side Diagnosis Procedure

IV. Troubleshooting Ground Loops & Pumps Closed & Open Loop Diagnosis

Anti-Freeze Selection and Installation Flushing & Purging Closed Loops

V. Hot Water Application- Installation-Diagnosis Hot Water Generators (Desuperheaters) Demand Hot Water Generation (Water to Water)

VI. Equipment Controls - Diagnosis and Troubleshooting CXM - DXM - CCM

VII. Equipment Installation

Start Up & Troubleshooting Procedures

VIII.Review & Exam

B. Contractor/Installer Training5


-Why are Geothermal Heat Pumps the Fastest Growing HVAC Market Today.

Federal Programs State Programs Your Utilities Programs





Low Maintenance & Durability

-How to Get Heat In & Out of the Earth Closed Loops & Pipe Types

I Domestic & Open Wells

Standing Column Wells


-How to Properly Size a Building for Heating & Cooling

Insulation ECH & EPA Energy Star/Building Programs Infiltration & Air Leakage Fresh Air?

-What's on the Heat Pump Market Today? Basic Single Stage w/EM Controls Multi-stage/Speed w/ Digital Controls Building Automation Controls


-Designing a GeoExchange System Earth Coupling Options Closed Loop Earth Coupling & Design Pumping & antifreeze Open Standing Column & Design Pumping & Options

Heat Pump Options Selecting from Catalogue Distribution Options Ducts

Radiant Floor Fan Coils Base Board. Recommended Design Packages

-Check, Test & Startup

How to test for water flows Classic/Ultra/Genesis

Commissioning Reports/How Well is it Working? BREAK

-Take a Look at the Industrial Geothermal Heat Pump Market -Questions & Answers

C. IGSPHA CERTIFICATION - Outline - (3 day)6 - for Engineers &Contractors CERTIFICATION OUTLINE

I- Introduction and Overview

2 - Economics, marketing and Demand Reduction

3 - Soils Identification

4- Selecting, sizing and Designing the Heat Pump system

5 - Designing the Ground Heat Exchanger

6 - Pipe Joining Methods

7- Installing the Ground Heat Exchanger

8- Grouting Procedures for Ground-Source Heat Pump systems

9 - Flushing and Purging the System

10 - Heat Pump Systems Start-up and Checkout

II- Accessories 12- Exam

D. Water-to-Water Geothermal Training for Engineers, Contractors & Utility Personnel7


Water-to-Water HP's, Fan Coils & Components - Catalogue

Specifications Fan Coil Selections Schematics Controls Trim Items DDC Interfaces

Geo-Coupling to the Earth

Closed Loops Horizontal Pond Loops Closed Loops Vertical Open Well (s) Slinkys

Standing Columns

Water Wells for Domestic & Heat Pump Use

Well Demonstrator & Components

Residential, Commercial & Industrial Markets Component Block Diagram Level -

Retrofit to Base Board Retrofit to AHUs A/C Addition Schools Radiant Floor

■ Warehousing

Water Heating Process Q Pools

Water Heating


Generating Requirements ( Heat Gains & Losses) -

Manual "J" residential Swimming Pools Manual "N" commercial Water Heating

Continue Residence - Component Selections

Hardware & Trim Items


Residential & Commercial Example Layouts & Components

Residential Retrofit Expandable Retrofit Multi-Zone New House Sample New Residence W-WHP Controls

Radiant Floors

Design Requirements Installation Options Component Selection/Piping Interfacing w/Geo-HPs Controls

Saving Well Pumping Costs

Schemes for Combined Domestic & Heat Pumps Use of Power Factor Controllers Electrical Trouble Shooting Well Pumps

Commercial Retrofit Example & Design - Layout

Library & Museum School


Continue Commercial Retrofit - Component Selections

Library School Museum Office Building rn

Installation Checkout & Startup

Water Balancing Heat of Absorption

Computing Efficiencies Heat of Extraction Antifreeze Solutions

"Mixed" Systems

Replace Boiler/Cooling Tower Water-to-Air & Water-to-Water Applications Cold Space Applications


1 A recently instituted certification program jointly administered by IGSPHA, GHPC and AEE

2 National Ground Water Association — Dublin OH

3 International Ground Source Heat Pump Association, Oklahoma State University, Stillwater OK

4 Courtesy ClimateMaster Corp

5 Courtesy of Water Energy Distributors Inc., Atkinson NH

6 Courtesy of International Ground Source Heat Pump Association, OK State University, Stillwater OK

7 Courtesy of Water & Energy Systems Corp, Atkinson NH

Performance and Ratings

9.0 Performance & Ratings

Appendix G provides a listing of commercially available geothermal heat pumps using open wells, standing columns and closed loops.


These heat pumps have been rated in the past by Air Conditioning and Refrigeration Institute (ARI). Since January 2000 the heat pumps have been rated by the International Standards Organization (ISO),

Past ARI ratings will still be used by many Manufacturers and will gradually transfer their ratings to ISO ratings. Past ARI Ratings are:

Earth Coupled Entering Liquid Commonly Called Heating Cooling

ARI 3251 "Well Water Rating" 50°F 50°F

ARI 330 "Closed Loop Rating" 32°F2 77°F

Entering Earth Water Temperatures for Various ARI Ratings

The ARI ratings only included procedures for rating Water-to-Air geothermal heat pumps and there were no rating methods for water-to-water heat pumps.

The ISO ratings include water-to-air geo heat pumps (ISO 13256-1) and water-to-water geo heat pumps (ISO 13256-2) rating methods.

Ratings are based upon similar, but somewhat different, entering water temperatures, they are:

Earth Coupled (Outside) Entering Liquids Commonly Called Heating Cooling

Entering Earth (OUTSIDE) Water Temperatures for Various ISO 13256-1 Ratings

Dry bulb and wet bulb temperatures for building (Inside) air temperatures are approx-

Iimately the same for the old ARI and ISO rating points.

It should be noted, ISO has adopted the terms "Outside" for the earth coupling ^»J water side and "Inside" for the building or load side of the heat pumps. Hopefully, to alleviate the continued confusion that exists between "ground", "well", "Condenser", "evaporator" and the myriad of terms used on both side of the geothermal heat pump.


Geothermal heat pumps are priced very similar to their "Building Loop" heat pumps with several exceptions that add some pricing to the basic heat pump:

1. Additional controls, e.g. thermostatic expansion valves to provide efficient operation with wide entering water temperature ranges, typically 20°F to 110°F

2. Larger control transformers for built in or auxiliary water flow controls

3. Larger heat exchangers to allow the wide temperature range operation.

4. If using well water the requirement for a copper-nickel rather than copper heat exchangers for enhanced reliability

As with all heat pumps the smaller the unit the higher the "Cost per ton" - small units and large units both require cabinets, electronic controls, manufacturing overhead - all of these are relatively independent of the size of the heat pump.

Typical averaged list price costing for several manufacturers are:

Size Range Typical Cost per Ton

Typical Geothermal Heat Pump Commercial List Prices - 2001

Including Copper-Nickel Alloy HX on Geo-Side

Adds to these costs are typically various factory applied options:

• Direct Digital Control Interfaces, e.g. LON Work and Bac Net

• Two-way Communicating Controls

• Quieting/Muting Packages

• Dual Compressor Heat Pumps

• Dehumidification Modes

• Hot Gas Reheat Systems

• Desuperheaters (Hot Water Generators)


Matching building loads to the Geothermal heat pumps is a must. Using "rules-of-thumb" for equipment sizing is not acceptable. Section 7 discusses geothermal heat pumps and their earth coupling system. The entire system must be matched to an accurate building heating and cooling/dehumidification load.

Geothermal heat pump systems (GeoExchange) have a wide variety of configurations and many are discussed in the document. A successful procurement for geothermal recognizes the dependant relationship between the earth, the heat pumps and the delivery terminals. It is mandatory that the three elements be under the same technical and administrative organization. Breaking out each of the three or even two of the three elements will lead to errors and fault finding and damaging bickering.

Always procure a GeoExchange system as a sole entity, do not break out components. If an HVAC contractor cannot take the responsibility for the entire "package" - find one that will

If there are existing wells on the site; determine the earth coupling requirements first and then have the well(s) tested to see if they will meet these requirements. Do not accept old well information as correct, it must be field verified.


9.4.1 Simple Payback

A simple pay back looks at the total price of an installation, the annualized savings and simply divides the two, with the result of so many years to payback the difference between a GeoExchange systems and a fossil based system. There are two ways to consider simple pay back for small systems of less than 350-400 tons;

Paying the first cost difference between the GeoExchange and an equivalent capacity fossil system - this difference is usually paid back in about 3 - 5 years.

Paying the cost of a completely new GeoExchange system installation as compared with keeping an existent fossil based heating and cooling system in place. - this difference is usually paid in 8 -12 years

9.4.2 Return on Investment (ROI)

A GeoExchange system can be a better investment than most conventional income investments. When considering the return on a down payment (e.g. 10% - 20%) for a building with a GeoExchange system the ROI for that amount of capital is often in the 20% - 30% range.

9.4.3 Present Value (PV)

PV is useful when comparing the GeoExchange investment with another investment. In a real sense this function will let the potential GeoExchange owner consider their investment in the Geo System as a source of an annuity.


In nearly all cases, there is almost always a positive cash flow when comparing a GeoExchange system to a competing fossil based system in the very first year.


The reliability and maintenance cost for the GeoExchange heat pump has been the subject of several factual studies over the past decade. The overall life of a water source/ GeoExchange heat pump has been evaluated in an Electric Power Research Institute report4 in 1988. Looking at a large population of actual heat pump installations, showed smaller water source heat pump had a mean time between failure (MTBF) of 46 years and large commercial water source heat pumps 19 years MTBF.

GeoExchange maintenance costs are more impressive with several site closely monitored in the past few years. GeoExchange installations have been recently evaluated by the U.S. Army5 and Caneta Research Corp6. GeoExchange heat pumps are shown to be lower maintenance costs than comparable gas or oil based heating systems.

The Table below shows the results of these studies:

4,003 buildings, U.S. Army Study, 30% reduction

Ft. Polk LA

25 Buildings (U.S. & Canada) 20% reduction

It should be noted that of the 25 building surveyed, 15 were schools. All of the schools were in Canada, New Jersey and Pennsylvania. School maintenance costs for GeoExchange heat pumps were evaluated for in-house and contractor maintenance:

GeoExchange Cost per Square Foot

Mean Cost Standard Deviation

In-House $0.0594 $0.0509 CT

Contractor $0.0697 $0.0618

School Survey of Maintenance Costs - Actual Labor Costs Averaged Over System Life

In the above table the approximate labor rate was $26.00/hour plus 36% Overhead and Benefits allocation.

A comparison of total Maintenance Costs from a 1985 Caneta Research Survey compared against an ASHRAE7 survey shows:

Caneta Survey ASHRAE Survey

Cost per Square Foot

Mean Cost Standard Deviation

$0.0732 $0.0692 Base Case, GeoExchange

$0.2180 $0.1640 Water Source Heat Pumps

$0.5220 $0.3380 Gas Absorption Chiller

Results of Recent Maintenance Studies, Commercial Buildings GeoExchange vs. Typical Fossil Based System

The ASHRAE survey included nearly 350 buildings and a variety of heating and cooling space-conditioning systems.

A recent study8 (1999) of four types of space conditioning systems in the Lincoln Nebraska Public School District compared these different heating and cooling systems in the District's 20 school buildings. The results do not include preventative maintenance and capital renewal in the 20 school data base.

Type Space Conditioning System Annual Cost/Square foot

Geothermal Systems $ 0.0213

Air Cooled Chiller w/ Gas Hot Water Boiler $ 0.0288

Water Cooled Chiller w/ Gas Hot Water Boiler $ 0.0373

Water Cooled Chiller w/ Gas Steam Boiler $ 0.0607

Operational Repair Maintenance 20 Schools - Lincoln Nebraska

These recent (1999) maintenance costs for geothermal are substantially lower than those report in previous studies, see above.

Reduced maintenance costs can be attributed to:

-Single machine provides heating and cooling, i.e. one piece of equipment replaces two or more items

-Geothermal heat pump systems are highly modular, i.e. multiple wells/ore and multiple heat pumps in a facility provide a high level of reliability -Geothermal heat pumps and their well/bore components have no unique components requiring periodic maintenance -other than air filter cleanliness Since the geothermal heat pump systems are highly modular many designers also specify emergency electric backup elements in the supply airside. As a backup, these electric elements can utilize the power service designated for the heat pump, when that local heat pump is in a failure mode. This is not a common requirement, but critical areas can be maintained in a freeze-proof condition using the same electrical service as the temporarily disabled heat pump.

To backup a geothermal heat pump system with a fossil system is not recommended. If a fossil backup system is specified this essentially triples the maintenance costs. The geothermal pump has been shown to reduce maintenance costs by approximately 50% - keeping the fossil system in place then adds that maintenance cost - with the resultant 150% maintenance cost, viz. 50% geo and 100% fossil.


Three different buildings representing three different building uses and types are evaluated for over all operational costs over a ten year period.

The above heating and cooling loads may not reflect the actual design and use characteristics of the buildings from which the loads and use profile data was taken. These buildings were selected as models to be used in the below analysis.

Each of these building types have been evaluated with a consistent set of economic assumptions. These and any other assumptions used in economic modeling must be verified before the results of any operational cost model are considered.

Summary results of these linear operational cost estimates are as shown in the table below. Payback periods are based upon simple payback of the differential costs of the geothermal over a natural gas fossil burning system.

Differential hardware costs must include added geothermal costs and avoided costs associated with a fossil based system, some typical added and avoided items are as listed below.

Added First Cost Wells/Bore holes Well/Bore Pumps Offset Piping & Installation Well/Bore Controls Site Work/Trenching Geothermal Heat Pumps Thermal Mass Tank (Water-Water HP)

2-Pipe Distribution System Roof-top Curbs, Penetrations & Access

Roof-top Rigging Housekeeping pads

Avoided First Cost Boiler Chiller

Cooling Tower (CT) CT Pumps CT/Boiler Controls Combustion Air Grills Site Gas Service Piping or Oil Tank

4-Pipe Distribution System Roof-top Weight Bearing Structure

Exterior Equipment Security Reduced Mechanical Room Size


Other factors as aesthetics (no exterior equipment), no need for operating engineers, no combustion products (possible fire insurance reduction), lower site maintenance (no fuel spills, Cooling Tower scaling or carbon deposits) and no Cooling Tower chemicals are factors that are more difficult to quantify in the first cost analysis but are important continuing operational costs, and must be recognized.


Differential Capital Cost (First Cost)

First Year Operational Cost Savings Ten Year Total Cost Savings Simple Payback

Carbon Dioxide Inhibited9

41 tons each year



Differential Capital Cost (First Cost)

First Year Operational Cost Savings Ten Year Total Cost Savings Simple Payback

Carbon Dioxide Inhibited

92 tons each year



(an attached row house on Reade Street in Manhattan)

Differential Capital Cost (First Cost)

First Year Operational Cost Savings Ten Year Total Cost Savings Simple Payback

Carbon Dioxide Inhibited

22.4 tons each year

High first costs are estimated for the three examples. However, it must be noted that estimates by the Geo Heat Center, Klamath Falls, Oregon10 have projected a cross over in installed geothermal costs at approximately 500 ± tons. Several larger geothermal heat pump projects have projected mcosts less than conventional fossil heating and cooling systems.

Energy Costs Electric $ 0.09 per kWh

Natural Gas

$ 0.78 per CCF (Avg 100mbtu/CCF) $ 1.10 per gallon (Avg 132 mbtu/gal)


Operational Hours11 Heating 1,500 Cooling 1,100

Gardens Residential

2,200 2,000 1,200 900

Equipment Efficiency


Electric Heat

Air-to-Air Heat Pump Heating Geothermal Heat Pump Heating

Heating Efficiency13 Natural Gas Boiler/Furnace

Light Oil (# 2) Boiler/Furnace Propane

Heavy Oil(# 4-6) - requires preheat

EER14 Cooling

Window Air Conditioner Air-to-Air Heating Pump Cooling

Geothermal Heat Pump Cooling 19.0

Cooling Tower & Chiller & Pumps 15.0


While these may not be the actual conditions for the actual building the economic model employed will have consistent and hence, comparative results.


1 An alternative ARI-325 rating for Southern States applications uses 70°F geothermal water for heating and cooling

2 At 32°F the rating includes a brine type antifreeze, brine is used as a standard antifreeze for evaluation purposes only. As it is not used in any actual applications it then becomes a universally accepted standard. Some antifreeze solutions may result in lower efficiencies than listed in the ARI or ISO standards.

3 At 32°F the rating includes a brine type antifreeze

4 Ross, Dr. David, PRA Inc. Pilot Study of Commercial Water-Loop Heat Pump Compressor Life, EPRI CU-6739, March 1990

5 J.Shonder & P. Hughes, Results from the Geothermal Heat Pump Energy Savings Performance Contract at Fort Polk LA, Oak Ridge National Lab, IGSPHA Conference, 10-1997

6 D.Cane et al, Survey and Analysis of Maintenance and Service Costs in commercial Building Geothermal Systems, Caneta Research Inc., RP-024 10-1997

7 ADM Associates, Analysis of Survey Data on HVAC Maintenance Costs (RP-382), ASHRAE Technical Committee 1.8, 1985

8 Martin, MA, Durfee and Hughes P. J, Comparing maintenance costs of geothermal heat pump systems with other HVAC systems in Lincoln (NB) public schools: Repair, service and corrective actions, ASHRAE Trans, 1999, Vol. 105, Part 2, #SE-99-20-04, 1208-1215

9 Although Natural Gas is a cleaner burning fuel than fuel oil, it none-the-less has a CO2 emission of 9-12 pounds of CO2 per CCF about 50% less than fuel oil.

10 Oregon Institute of Technology - Klamath Falls Oregon, [email protected]

11 ARI Standard 210 Lists New York City area as 2,400 hours heating and 700 hours cooling; these are modified by the typical use and urban building configurations, e.g. two of four walls are party walls, the effects of passive solar and estimated use profiles. From building to building these key numbers will vary. Hour-by-Hour simulations or a rigorous derivation from existing energy bills can provide relatively accurate values for these evaluations.

12 Coefficient of Performance (COP) typically used for Heating efficiency evaluation worldwide. COP is the ratio of the purchased energy (electric) cost verses the output of the space heating equipment as measured by the same units, e.g. watts, calories, Btu etc.

13 The efficiency of the fossil burning equipment also includes the cost of parasitic electricity, i.e. the cost of running the motors and controls in these devices. These costs are only a smaller portion of the overall equipment efficiency

14 Energy Efficiency Ratio (EER) typically used in the United Sates for Cooling efficiency and is the ratio of Btu performance verses the amount of purchased energy in watts.

Summary of Refrigerant Types used in Geothermal Equipment i ns

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