How to use GAHT or Ground to Air Heat Transfer System (aka earth tubes) for heating and cooling?

I'm planning on using earth tubes similar to how Citrus in the Snow uses them, but for home heating and cooling. My thought is to simply use the ~55ºF in the summer by pumping it to the ventilation system during the summer. Then during the winter I want to us it as a baseline to get/keep temperature up to the 55ºF mark and then raise the temp up from there as needed.

Any experience in setting up such a system for cooling + heating?

I've been told that I'd need to watch out for moisture and mold issues in the tubes, etc. but I can't help but wonder if that will really be an actual problem from what I've seen from Citrus in the Snow.

Any thoughts?

A bit more detail is needed. What is the system you speak of?

This Geo cooling/heating system is used by the creator of https://greenhouseinthesnow.com/
It is mentioned in the video on that website page.

Adriaan van Roosmalen wrote:This Geo cooling/heating system is used by the creator of https://greenhouseinthesnow.com/
It is mentioned in the video on that website page.

That is correct. They're also calling this GAHT or Ground to Air Heat Transfer System, see: https://www.youtube.com/watch?v=dzRh4GJDMD8

Clearly the idea is to get some effect similar to this for the temperature during the year: https://www.youtube.com/watch?v=sxqlh6kJ_9s

Here is a fellow who took this idea and applied it to a house, but I'm not clear on the details past getting the temperature to the house. Maybe his accent is just too hard for me to understand clearly:

1. https://www.youtube.com/watch?v=l4nMsHqCTeI

2. https://www.youtube.com/watch?v=Prd3Pf1h4hQ

3. https://www.youtube.com/watch?v=Aa-D4mVydhw

4. https://www.youtube.com/watch?v=GCJOgwKKNcw

I've not gone through this guy's stuff yet (concerned with some comments about him not knowing what he's talking about) to see if he has some details about this, "Earth Cooling Tubes for Ventilation and Climate Control" Parts 1-3:

1. https://www.youtube.com/watch?v=fYq29h2eEH8

2. https://www.youtube.com/watch?v=cDmY2xzsens

3. https://www.youtube.com/watch?v=OoaEND7HWzA

This guy seems to discuss two geothermal systems in comparison for a greenhouse (he says 3.5 feet is enough for tube burying in Pacific Northwest) and someone says he seems nervous about the "outcome of his endeavor":

https://youtu.be/clN45rjGbpo?t=715

This presenter has a very interesting vertical take on the geothermal earth tubes (in Denver, Colorado), again for greenhouses, but seemingly applicable:

1. https://www.youtube.com/watch?v=e8AosXQ3OaA

2. https://www.youtube.com/watch?v=ghmvI9U1KQI

3. building: https://www.youtube.com/watch?v=Qh3-iTJvVR4

4. 2.0, letter "U" shaped with compost - part 1 design: https://www.youtube.com/watch?v=Ze0nXN6Vvic

5. 2.0, part 2: https://www.youtube.com/watch?v=VtPfUy6T2Jc

6. 2.0, part 3: https://www.youtube.com/watch?v=Dm7fQQrKlSs

7. 3.0, part 1 (some really nice ideas in this one): https://www.youtube.com/watch?v=A2TQJl9WjLc

8. 3.0, part 2 - results: https://www.youtube.com/watch?v=ch0VD-_9Xxc

9. 3.0, part 3 - convection achieved; more results with hot compost: https://www.youtube.com/watch?v=eMHbHAKeMC0