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A Geothermal Heat Pump fits in place of existing air handler/furnaces

Ten “Myth-stakes” You Need to Know When Installing a Geothermal System

So you’re thinking about installing a geothermal cooling and heating system? You can do this, and you have the means to install the best system money can buy for a fair price. There are a lot of competent geothermal HVAC professionals that are willing to help. As in any transaction, you just need to be educated enough that you can “talk the talk” with your geothermal folks.

Knowing that your installation is likely different than anyone else’s geothermal cooling and heating system is important. Like a custom-tailored suit, or a master bedroom closet organizer, you have the ability to get what you ask for if you to take the time to work through the details. It’s likely that your mind will be changed along the way about a few things, and that’s OK. Use wisdom, and for goodness sake, don’t be in a hurry. The moment you make hasty decisions, you begin to lose some control. (For more general information, see related post: 10 Myths About Geothermal Heating and Cooling.)

How It Works: The Basics

Replacement of a standard heating and cooling system with a geothermal heat pump will result in a remarkable tidy and simplified HVAC system. The GHP will likely go in the same place that your air-handler is installed right now.

The outside condenser or compressor section will be eliminated, and the connecting refrigerant lines will be terminated.

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Outside equipment and associated refrigerant lines are eliminated.

A permanent closed loop heat exchanger or well system will be installed on your property (and will last for generations).  You may even have the privilege of connecting to a community geothermal ground-loop

Convenience and performance upgrades available on standard heat pumps will be available for your new geothermal heating and cooling systems. Take your choice of premium air filtration, web-enabled controls and touch-screen thermostats if you like. Plus, you can have domestic hot water and pool heating options, as well as radiant floors.

Myth-stakes” that you should know about:

1. A geothermal heat pump is expensive and I won’t be able to afford/finance a new one.
Many manufacturers have financing, and federal and local incentives typically amount to between 30 and 60 percent of total geothermal system cost, which can often make the initial price of a system competitive with conventional equipment.

2. Geothermal is way above my head technically. I feel I should leave textbooks and schools to the experts.
Read up. Read up. Then, if you have time, Read up! Why else do you think we freely use terms like “Quad Core Processor” and “Regenerative Braking”? Download a geothermal book onto your Kindle, or pick up a hard copy of something with a good index for reference. It’s even worth your time to attend a one-day class. Check for something coming up in your area @

3. My geothermal dealer knows better than I do what arrangement will work for me.
Your geothermal contractor is likely highly trained and competent. But he may not know what works best for you any more than your auto mechanic knows what brand and model of car you should buy. His input is valuable, but use wisdom and prudence. Don’t be intimidated, or rushed into a choice.

4. The geothermal install I saw on television is exactly what I want.
What works well in Wimauma, Florida, may be different than the best bet for Bakersfield, California. From equipment types to geothermal sources and from air filtration to duct design; most importantly, from “that guy’s install” to yours, the parameters change. Glean the best of all of your preferences, and couple that with regional design precedents and parameters and you’ll end up with the perfect geothermal heating and cooling system for you.

5. My new geothermal heat pump must go where my old air handler was located.
Usually, the old location will work, but consider all of the options. Sometimes it’s favorable to move an attic-installed air-handling unit to the garage or a hall closet. Why? Ease of service, and sometimes longevity. An attic, while sheltered from direct exposure to elements, may still experience some treacherous temperature and humidity swings.

6. My expensive [fill in the blank] won’t work on my new geothermal heat pump.
Correction: “[fill in the blank]” means things like: zone controllers; UV lights; humidifiers; filtration; premium thermostats; cccupancy sensors; carbon dioxide monitors; fresh-air ducting; ERVs (energy recovery ventilators), and other extras you may currently have on your standard heat pump. With few exceptions, all of the extras will work with your geothermal system.

7. I will need to be without AC or heat the entire time they’re drilling my new geothermal wells.
Not so: Careful planning will enable you to keep your existing heating and cooling systems up and running right up to the day they install your geothermal heat pump. If everything is terminated right up to that location, the job becomes a reasonably simple one day change out. This is directly related to your involvement in the planning process.

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A “Standing Column Well” is only one of several choices for your geothermal source

8. I will have to hire multiple contractors (HVAC, Electrical, Driller, Plumber, etc.)
It will often be easier on you to deal with one contractor to reduce finger pointing and related delays. There is good reason to choose your primary contractor wisely.

9. The 30 percent tax credit covers only the heat pump and geothermal loop/well.
Not only does it cover most of the peripherals, but there are often other incentives locally. Check the Database of State Incentives for Renewables and Efficiency to find out what other surprises may be in store for you. You will find that swimming pool and spa heat pumps are considered a luxury item, and they are not covered. However, these luxury items can actually help overall performance and share your thermal load.

10. Always follow the owner’s manual for the best installation guidance.
The owner’s manual is a great starting point, and should be considered at all levels. However, there is always room for improvement. As an example, some diagrams for connecting a domestic hot water generator to the hot water tank is fundamentally correct, but can be greatly improved by adding a “buffer tank” which costs only a few hundred dollars.

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Adding a “Buffer-Tank” will further improve energy savings (Illustration, Sarah Cheney)

With a 30 percent federal tax credit and the highest energy efficiency available, geothermal heat pumps are affordable and reduce electrical consumption. Geothermal is a mainstream technology; treat yourself to the benefits of a geothermal heat pump in your home.

So what are you waiting for? You can do this! Comment here or email me if you have any questions; I’m here to help!

Jay Egg is a geothermal consultant, writer, and the owner of EggGeothermal. He has co-authored two textbooks on geothermal HVAC systems published by McGraw-Hill Professional. He can be reached at .