Commercial Design for Commercial Design for

Geothermal SystemsGeothermal Systems

STARTING OUT RIGHTSTARTING OUT RIGHT

Develop a design team.Develop a design team.

Examine site for best loop options.Examine site for best loop options.

Determine building zone loads and block loads.Determine building zone loads and block loads.

Select loop length with software - individual loop Select loop length with software - individual loop or peak block load.or peak block load.

Select pump for single unit or central pump Select pump for single unit or central pump design.design.

Zone load determines unit selection for space. Zone load determines unit selection for space.

Block heating/cooling load determines loop length. Block heating/cooling load determines loop length.

Hybrid design should be considered on jobs with Hybrid design should be considered on jobs with excessive gains (rejection). excessive gains (rejection).

Fresh air may require special considerationsFresh air may require special considerations

–Hot Water ReheatHot Water Reheat

–Water to Water with hydronic coilWater to Water with hydronic coil

–Heat Recovery equipmentHeat Recovery equipment

BUILDING LOSS / GAINBUILDING LOSS / GAIN

Vertical, Horizontal, Downflow, Console, Rooftop, Vertical, Horizontal, Downflow, Console, Rooftop, Water to Water, and Split configurations Water to Water, and Split configurations available.available.

Design using equipment rated to match loop Design using equipment rated to match loop temperatures.temperatures.

Select equipment using 35°F EWT for heating and Select equipment using 35°F EWT for heating and 95 to 100°F EWT for cooling.95 to 100°F EWT for cooling.

Design airflow approximately 400 CFM per ton.Design airflow approximately 400 CFM per ton.

Design geothermal closed-loop water flow rate Design geothermal closed-loop water flow rate 2.5 to 3 gpm/ton.2.5 to 3 gpm/ton.

GEOTHERMAL UNIT SELECTIONGEOTHERMAL UNIT SELECTION

Vertical3/4 to 20 ton

Horizontal3/4 to 10 ton

Water-to-Water1 to 30 ton

PRODUCT LINEPRODUCT LINE

Console1/2 to 1-1/2 ton

Rooftop3 to 22 ton

HEAT SOURCE & SINKHEAT SOURCE & SINK

BOILER/COOLING TOWERBOILER/COOLING TOWER

OPEN LOOPOPEN LOOP

CLOSED LOOPCLOSED LOOP VERTICALVERTICAL HORIZONTALHORIZONTAL PONDPOND

BOILER/COOLING TOWER

Excellent for buildings where space is not Excellent for buildings where space is not available for a closed loop system.available for a closed loop system.

Cooling tower can be used in conjunction Cooling tower can be used in conjunction with a closed loop for a very cost-effective with a closed loop for a very cost-effective system for cooling-dominant applications.system for cooling-dominant applications.

High efficiency geothermal equipment High efficiency geothermal equipment enhances operating cost savings of an enhances operating cost savings of an already proven technology.already proven technology.

BOILER/COOLING TOWER

OPEN LOOP

OPEN LOOP

Very cost effective, provided the following Very cost effective, provided the following are verified:are verified:

–Water quality is highWater quality is high

–Water quantity is sufficientWater quantity is sufficient

–Discharge location is availableDischarge location is available

–Meets codes/standardsMeets codes/standards

VERTICAL LOOP

Keeps space needed for a closed loop to a Keeps space needed for a closed loop to a minimum.minimum.

Requires 250 square feet of surface area per ton.Requires 250 square feet of surface area per ton.

Each bore 180 to 300 ft. deep depending upon Each bore 180 to 300 ft. deep depending upon application and climate (use software).application and climate (use software).

Holes filled and sealed with grout. Holes filled and sealed with grout.

Most expensive first costs - $1,000 to $1,300 per Most expensive first costs - $1,000 to $1,300 per ton.ton.

VERTICAL LOOP

VERTICAL LOOP

Circuits

Runouts

Geo-ClipsGeo-Clips

Devices used to keep pipe separated in bore Devices used to keep pipe separated in bore hole for optimum performance.hole for optimum performance.

Vertical Loop Installation

Loops Installed Under Baseball Field at High School

Cost effective when land area is plentiful.Cost effective when land area is plentiful.

2500 sq. ft. per ton required.2500 sq. ft. per ton required.

Various methods and piping arrangements, Various methods and piping arrangements, depending upon available space.depending upon available space.

200 to 400 ft. of trench per ton, depending 200 to 400 ft. of trench per ton, depending upon climate and loop type.upon climate and loop type.

Installed costs - $600 to $800 per ton.Installed costs - $600 to $800 per ton.

HORIZONTAL LOOP

RUNOUTSCIRCUITS

HORIZONTAL LOOP

POND LOOP

Pond depth 10 to 12 feet minimum.Pond depth 10 to 12 feet minimum.300 to 350 feet of 3/4 inch P.E. coil per ton.300 to 350 feet of 3/4 inch P.E. coil per ton.30 to 50 tons of 30 to 50 tons of coolingcooling per surface acre. per surface acre.10 to 20 tons of 10 to 20 tons of heatingheating per surface acre. per surface acre.Northern projects favor mat loops.Northern projects favor mat loops.$400 to $700 per ton.$400 to $700 per ton.

POND LOOP

2 Tons

3 Tons

4 Tons

POND LOOP

Coil spacers increase thermal performance.

Pond loop assembly

Vertical:Vertical: - GchpCalc by Steve Kavanaugh- GchpCalc by Steve Kavanaugh

–GLHEPRO by Oklahoma State.GLHEPRO by Oklahoma State.

Horizontal: -WrightSoft (residential software).Horizontal: -WrightSoft (residential software).

Pond Loops: - Use consultant (Loop Group).Pond Loops: - Use consultant (Loop Group).

Software patterns heat transfer to and from soil Software patterns heat transfer to and from soil (storage) to account for long term effects.(storage) to account for long term effects.

Conductivity Testing Recommended.Conductivity Testing Recommended.

Thermally enhanced grouts available.Thermally enhanced grouts available.

LOOP SIZING SOFTWARELOOP SIZING SOFTWARE

CENTRAL PUMP STATION

SUCTIONFROM CLOSED LOOP

EXPANSION TANK

SUCTIONDIFFUSER

TRIPLE DUTY VALVE

CENTRIFUGAL PUMP

DISCHARGETO CLOSED LOOP

AIRSEPARATOR

CENTRAL PUMP STATION

INSIDE PIPING

Central Pump

Core Units

Perimeter Units

INSIDE PIPING

Commercial & Institutional InstallationsCommercial & Institutional Installations

Offices Offices Schools and UniversitiesSchools and UniversitiesRetail, Restaurants, MallsRetail, Restaurants, MallsHotels, Motels, ResortsHotels, Motels, ResortsApartments and CondominiumsApartments and CondominiumsHospitals and Health CareHospitals and Health CareScience Centers and MuseumsScience Centers and MuseumsPools, Greenhouses and Fish FarmsPools, Greenhouses and Fish Farms

Offices

Schools

Hotels & Resorts

Multi-Family & Military Housing

And many other types of applications including restaurants, retail, pools, hospitals, museums, nursing homes...

Contact WFI Commercial Department for Design

Assistance