# Loop depth!

Discussion in 'Geothermal Loops' started by Wiley HVAC, Nov 29, 2011.

1. ### Wiley HVACNew Member

Sorry but no, the explination the other tech is giving me is that the ground is storing the energy for the next season! That cant be in the picture I have of how a geothermal loop works!

My thought on it is that its a constant temperature in the ground and that due to the length of loop and contact with the earth that the btu transfer is due to the constant temperature. And that is where the energy savings is, kinda like operating an air to air heatpump in 55-60 degree outdoor temperatures.

His theory is that the system is running in the winter and storing the energy from the loop for the summer months, and vice versa in the summer. His explination is that the earth around the loops is now like a storage vault, and that from season to season they are reusing the energy they are putting into the vault if you will! I dont see any similarity between what his discription is and what my understanding is..

This tech also tells everyone around us that a vertical loop is the only way a geo-thermal loop can work. I have seen several horizontial loops put in and work effeciently, not to mention open loops and pond loops as well. I run into the arguement that here in Kentucky that the geography will not allow a horizontal loop to work properly. I have no idea of where to look to find info to back the horizontial design!

2. ### waterpirateWell-Known MemberIndustry ProfessionalForum Leader

While we wish that every tech would seek a plane of higher learning, it is not allways the case. I have heard and been told just about every D- explanation and dumbed down version of geothermal imagineable. That being said, it really does not matter what they say, if they pull off good, clean, working systems.
At the end of the day there is no "geothermal police" to correct these isues. Only pro's who toil away in success.
Eric

There is an easy way to describe it that I've heard. Imagine putting your refrigerator on 55 degrees. Now put a Bowl of hot water in the refrigerator. Your hot water will slowly return to 55degrees , no matter how many bowls of hot water you put in it. Your will may temporarily raise the refrigerator temp to 56-58 degrees but it always return back to 55 degrees. Same theory with geothermal.
To the Pros: I know it sounds silly, but me of my customers explained to me that way and it works. SO...... I'll use it here LOL

4. ### Wiley HVACNew Member

So I am still not clear, is his theory right on the earth storing energy for the nexy season or is it based on a constant temperature?

I sat through a WaterFurnace class on HE/HR and what I took from the class was that the ground is absorbing the energy or adding to it through the constant emperature! I

No you are storing energy. The earth is absorbing the temp. And tranferring heat.

Sorry. Just noticed damn iPad is auto correcting me. The earth is NOT storing your energy. it is simply absorbing the temp, wether it be heat or cold.

7. ### Wiley HVACNew Member

And this is due to the large amount of btu transfer, be cause of the transferance of the vastly larger continous steady temperature of the ground no matter if it is 200 feet down vertically or 8' horizontially! I thought I heard correctly, I just wanted to get another persons opinion!

8. ### Palace GeoThermalWell-Known MemberIndustry ProfessionalForum Leader

A horizontal loop can store some heat from the summer for the heating season and vice a versa.

My slinky loop starts each heating season about 10 degrees warmer than the surrounding ground and each cooling season about 10 degrees cooler than the surrounding ground.

This is called the "flywheel effect"

Last edited: Mar 21, 2012
9. ### docjenserWell-Known MemberIndustry ProfessionalForum Leader

Vertical loops cool down quickly due to their smaller size. Horizontal loops are larger and connected to more ground. We also see 10-12 degrees higher entering water temp at the begin of the heating season slowly decreasing until end of December. After that there is no difference anymore between loop with A/C heat rejection in the summer, and loops without A/C.