The Geothermal Heat Pump Open Loop & You!

Whether you are attracted to the long term reliability or the energy efficiency, you've decided you want a geothermal heat pump for your home. But these are not a one-size-fits-all technology. There are lots of choices to make. For example, is a geothermal heat pump open loop a good fit for your needs?

Ground-Source Tech

For those who don't know, what is a geothermal heat pump?

Conventional air conditioners and heat pumps rely on the Earth's atmosphere as a standard part of their operating cycle. Geothermal units do not. They use the Earth itself as both a heat source and heat sink. That's the environment a ground-source system will leverage to deliver high performance all year long.

Geothermal Heat Pump Open Loops

Every geothermal system interacts with the Earth via some medium. A closed loop installation uses buried pipes with coolant running through them.

Open loop systems (obviously) don't work the same way. A geothermal heat pump open loop engages directly into a well or surface body of water. They do not require extensive buried piping. Thanks to their heat exchange medium and operating requirements, not only can they be cheaper to install, but they can also operate at higher efficiencies.


Why wouldn't everyone want the higher efficiency and lower cost of an open loop?

They would, but an open loop installation isn't always possible. Local water chemistry must be gentle enough to not wear down the system over time. Water chemistry can vary across the country. and some regions simply don't have the right kind of water to support an open loop.

Many local municipal governments also restrict emissions into the water table. For these reasons there are lots of areas where an open loop is inadvisable or illegal. That being said, if local ordnance allows and your local water chemistry meets certain guidelines, an open loop geothermal heat pump installation could save you a lot of money in the coming decades.

If you have questions about open loops or other geothermal systems, just ask in the comments below.

30 comments (view/add)
  • Ethan Morton
    Ethan Morton
    Posted on 1/31/2021

    What it be possible to filter the water coming in to an open loop system to bring TDS and Iron ppm down to a tolerant level? For instance, having a whole house filtration system?

    Also, what is the general usage of water per unit that way I know I have a well big enough to keep up with demand? I knows it’s dependent on actual usage, but there has to be some parameters for sizing the equipment to an appropriate size?

    Thanks a latte

  • Dan Danowski
    Dan Danowski from Ingrams
    Posted on 2/1/2021

    Yes, you can filter the water going into a geothermal heat pump. You would need to get the water tested to find out your TDS and iron PPM. From there you can get a proper filtration system for a whole house or even commercial sized filtration depending upon the geothermal unit/units size they are going to be using. Plan on each unit using 2-3 GPM per ton, and from those numbers calculate the needed capacity for the well and the capacity of the filtration system. Be sure and include the rest of the house if using well water for showers, sinks, etc. If you have hard water and do not want salt, you can do something like for normal use or for larger capacity. A high TDS does not always mean scaling on water features, but if you have it then that will be helpful. Otherwise, a good filter will go a long way in removing the TDS.

  • Dale Voss
    Dale Voss
    Posted on 5/24/2020

    Hello Kyle,
    I live in Vero Beach Florida currently have a 3 ton geothermal open loop system its 27 years old and still going.
    Here is my water report
    Can your ITEM: HA18838 MODEL: GCHPH048TGTANXX be able to use my well water?
    Regards Dale

  • Kyle
    Kyle from Ingrams
    Posted on 5/27/2020

    Hi, Dale. Your TDS is high but acceptable. Your PH is fine. I am not familiar with what the H, I and TAN numbers represent. If the I is iron, generally no iron content is acceptable. The GCHPH models all use a cupro-nickel heat exchanger so most groundwater is acceptable for use with this unit.

  • Erious Johnson
    Erious Johnson
    Posted on 4/14/2020

    Is a closed loop geothermal unit compatible in New York City. And where can I get info about geothermal heating

  • Kyle
    Kyle from Ingrams
    Posted on 4/15/2020

    I don't know about the particular of NYC regulations. However, a closed loop geothermal system is 'closed', so there is not reason why it should be any more or less regulated than a typical heat pump. You can find out more about geothermal heating with our Geothermal Heat Pump Buying Guide or just by searching 'geothermal heating' on our site.

  • Michael Garns
    Michael Garns
    Posted on 12/29/2019

    Do you test water to see if it is suitable for an open loop?, or do you have a standard for water Quality?



  • Kyle
    Kyle from Ingrams
    Posted on 12/30/2019

    We don't provide water testing ourselves, but there are definitely tests that can be conducted to see if groundwater is suitable for open loop. Ideally, you want water with a pH balance that is neither too high nor too low, and you don't want too much mineral content that can lead to scaling.

  • Jim Hennessy
    Jim Hennessy
    Posted on 9/12/2019

    Trying to puzzle out previous geothermal unit and all the plumbing in Florida.
    Need to talk.

  • Kyle
    Kyle from Ingrams
    Posted on 9/13/2019

    Sure! We'd be happy to talk anytime. Give us a call at 270-575-9595, and talk to Jacob, our in-house geothermal expert, at x103. He can help you get to the bottom of any geothermal problems you might be having.

  • Duane Schillemat
    Duane Schillemat
    Posted on 7/22/2019

    I would like installation and description of an open loop system. I have worked in the water well industry for 30 years so I have some very specific questions. I have a good understanding of the basics . I want to know the advantages of a air handler system or baseboard. I have hot water baseboard for my heat. If I use the baseboard would I have options for air conditioning? Would it more efficient and cot effective to put in an air handler? Are multiples available?

  • Kyle
    Kyle from Ingrams
    Posted on 7/23/2019

    In an open loop system, the geothermal unit is connected directly to groundwater or another water source. The water comes directly into the system, and then passed directly out of the system. This is a very effective way to run a system, but many municipal codes do not allow it.

    It is possible to get both heating and cooling from a geothermal radiant floor system. Efficiency between radiant and air handler heating/cooling is hard to determine without more detail, since there are many factors at work. Radiant cooling isn't terribly common in residential applications, but it is possible. The downside is that radiant cooling does not reduce interior humidity.

  • Sonja Edwards
    Sonja Edwards
    Posted on 4/7/2019

    I need A LOT more info before I buy a kit. I couldn't find it on your website. Do you have an installation manual?

  • Kyle
    Kyle from Ingrams
    Posted on 4/8/2019

    Give us a call at 800-360-1569 and talk to Jacob, our in-house geothermal expert, at extension 103.

  • Sonja Edwards
    Sonja Edwards
    Posted on 3/21/2019

    I have a well but the water has a lot of iron in it. Would that be a problem in an open loop system? Also, how much water is going to be dumped on a daily basis?

  • Kyle
    Kyle from Ingrams
    Posted on 3/22/2019

    Iron in your water could cause fouling or scaling problems. The amount of water being dumped depends on the unit. Roughly 2-3 gallons per minute per ton is a decent rule of thumb.

  • Jeff Cobb
    Jeff Cobb
    Posted on 3/6/2019

    I am putting in a new well to handle the geo system. The old well is about 10 feet from the new well. Can i pump the water back into the old well or is 10 feet too close. South west Michigan 49 degree ground water temp.

  • Kyle
    Kyle from Ingrams
    Posted on 3/18/2019

    It depends on the depth of the wells and direction of underground water flow. If the old well is downstream or on a different water table, you should not have a problem.

  • Kate
    Posted on 1/11/2019

    We had a Trane open loop system put in 6 years ago. We have had nothing but problems and bills. Our tech tells us it is because when the temperature gets below 30 degrees the well water is too cold from the dumping back into well. We have had thousands of dollars worth of bills. Is this true? Also the cause of bills coil replacement, valve problems, not switching to back up heat, system locking out.

  • Kyle
    Kyle from Ingrams
    Posted on 1/15/2019

    If you're using an open loop system and dumping the water back into the same well you're pulling from, it can cause major problems during winter. Basically, every time the water goes through the system it drops 8-10 degrees. If that water is going back in the well, it will quickly lower the temp of the well below usable temp and would have to run heat strips for heat. And probably kick the system off for low incoming water temp. In this scenario, you need to dump the water into a secondary well or creek, pond, lake, or somewhere that is not the same well.

  • Thomas mulryan
    Thomas mulryan
    Posted on 12/5/2018

    Purchased a geocool 1048 thru jarrard..very happy with his service..wondering if anywhere i can find some pictures or videos of the unit installation..using or should say replacing a Trane open loop..would like to se some different ideas s7nce tbe condensation outlet is so close to the floor and the unit will be seen front and right side when you walk into the house from lower level coming into the house from garage ...the room is finished off..left hand return with top output with 15 k heatstrip from you ..thanks ..everyone there is so helpful

  • Kyle
    Kyle from Ingrams
    Posted on 12/6/2018

    We have some geothermal install videos on ( You can also check out Ingram's Water & Air Equipment on YouTube for more. Also, you can always call and talk to our in-house geothermal expert, Jacob, at 800-360-1569 x103.

  • Stephanie
    Posted on 10/12/2018

    We're Going to build a new home in Northern Nevada (Elko) area on a 48 acre lot. We'll Need to drill a well and a septic tank. Would like an Open Loop GeoThermal system for heating and cooling as well as hot water. Is there a GeoThermal attachment water heater tank so we don't need to get propane to heat the water? how would that work? Can't find anything on this website about Geothermal hot water attached to the air system, but did find a ClimateMaster video on YouTube No information is listed regarding Hot Water & Hot air, Cool Air.

  • Kyle
    Kyle from Ingrams
    Posted on 10/15/2018

    There is a desuperheater. It's a component you can use to get hot water from your geothermal installation. Call us at 800-360-1569, and talk to Jacob, our geothermal expert, at x 103.

  • Brenda Johnson
    Brenda Johnson
    Posted on 8/24/2018

    My son just purchased a home that had a natural gas water heated coil heat system. However, due to the cold winter with no one in the house the coil had burst. Is this system efficient or should he change to a natural gas fired furnace?

  • Kyle
    Kyle from Ingrams
    Posted on 8/24/2018

    Just about any system can be efficient, relatively speaking. Do you have the name or model number of the system he is currently using?

  • Jeff Johnson
    Jeff Johnson
    Posted on 8/24/2018

    Can I use an inground swimming pool as a closed loop system. I have a 16 X 34' pool that holds approx 25,000 gallons of water. It is 9' deep on the last 7' of the pool.

  • Kyle
    Kyle from Ingrams
    Posted on 8/24/2018

    An Olympic-sized pool would be sufficient, but a typical swimming pool would not be. You would need a lot more length to accommodate the loops. Interesting idea though!

  • Randy Bargen
    Randy Bargen
    Posted on 8/23/2018

    Sir, I live in the country, use a well for water, could I use that water as my grd source water and then use it in the rest of my house? On really hot days, I could run a trickle sprinkler around my wife's flowers and thru household use, would that be ok or why not? During the winter, I may have to take an extra shower or flush the toilet, what do you think? I have put extra insulation in the attic and am considering a attic fan in the garage as a way to reduce the heat in the house to reduce heat that needs to be taken away. Has anyone else thought of this of using the open loop system in the house.

  • Kyle
    Kyle from Ingrams
    Posted on 8/23/2018

    Our geothermal expert, Jacob says,"You can use the water for other things, yes. I don't know if you would want to drink it, but I suppose it wouldn't hurt. You are not changing the water in anyway except the temperature of it. You just need to have a plan to discharge the water not being used after the geothermal. Diverting some of it to the garden, yard, farm animals, whatever is fine. You could put a valve on a timer to open up and allow water to go where you want it when the system is being used, then have it close outside of those times to discharge the water to the main dump area like the ditch, creek, pond, lake, or secondary well." So, yeah, your idea should work, Randy. If you have other questions, you can ask them here or you can reach Jacob directly at 800-360-1569 x103.

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