DIY Digging trenches for Geothermal

[Gofast]

I am looking at digging my own loop field. Two trenched 300 long 6 deep.
I would buy a 16" bucket to do this job.
I have a potato plow and I was thinking about using to start off the trenches.
It may save some digging time.

Has anyone else done this job or dug long deep trenches.

 

[Code54]

Having dug several larger trenches I don't really think it will matter much if you are using a decent sized hoe or Mini Ex. On the mini I ran a 4' deep water line trench the other day, maybe 30+ feet (little trench, 12" wide bucket for this one), dropped the line in and burred it in about 30 or so minutes. The small amount of dirt moved with the plow won't take more than a minute on the machine so by the time you change the implements, adjust, plow, put away you could have just dug it and been done.

 

[Code54]

On another note, if you are planning on doing with with a sub compact it will be a LONG project. Digging that deep is very slow on a small hoe since you need to move the machine every foot or two. Rent a Mini Ex and you can knock it out in no time with a LOT less effort.

 

[Gofast]

We posted at the same time

I want to use my CG 1710 I know a mini Ex will be much faster but I really want to use what I have. I have been able to move my tractor with just the hoe with out getting off the tractor.
I just lifted the front end loader and out riggers used the hoe to move the tractor forward.

This weekend I may dig a test trench and time it. First 3' goes fast but I need to test dig deeper.

 

[edgarrian]

Not sure what your depth of the hoe is on tractor but I believe it will depend on the ground ur digging. The type of soil. If its sandy material then you should use an excavator for safety reasons. If its clay and ur trench starts getting water in it. Becarefull when working in a 6ft deep trench as the side can cave in. If you need to fold back the edges of the trench to prevent cave in then do so. As I said this really depends on your type of soil

 

[Diggin It]

At 6' deep, you'll be at the maximum depth. At 600' you may be over stressing the machine. These are made for casual digging, not production work.

Can it be done? Maybe. I haven't tried digging a trench yet, and I haven't gone below about 3' and I'm not sure I would want to.

 

[3Ts]

How wide is your trench? If it's only one bucket width wide it will be easier. I had to dig a hole 9' x 11' and 8' deep with my backhoe (18" bucket) and the depth was close to it's limits. I had to dig along one side move the tractor over to the other side to get the width, then move forward about a foot and repeat. Then there is the spoil. It makes a pile taller than I could reach so I had to spend time moving it back as well. It's a long process but can be done. Be careful, those depths can be dangerous from both falling in and from cave-in.

 

[shooterdon]

I understand the DIY aspect and wanting to use that BH you invested in. But there are times farming out the job makes sense. My concern woukd not be the time it takes, but I am retired; or the stress on the machine, just go slow. My concern is the safety aspect.

 

[buckeyefarmer]

I bought my BH92 for that very reason. I dug 5 trenches 70'x3' wide for slinkies. 18" bucket. Do not remove soil first, it will make it worse. Did not take too long. Doing the geo install myself instead of "farming it out" paid for the tractor and backhoe.

 

[Gofast]

Looks great how many ton unit did you put in? what MFG did you go with on the Geo unit?
How deep did you dig?

 

[Tompet]

I bought my BH92 for that very reason. I dug 5 trenches 70'x3' wide for slinkies. 18" bucket. Do not remove soil first, it will make it worse. Did not take too long. Doing the geo install myself instead of "farming it out" paid for the tractor and backhoe.
View attachment 579832View attachment 579833

I had the predecessor of the op's 1710 (gc2310) and your bh92 is different level machine that would be successful for the project.

Best idea as op and another poster said is dig a test trench/hole 6' deep. You will experience the difference of task from digging a 2 or 3 feet deep trench with your machine.

Reread Digginit's post...take that advice in consideration too. Post what you think after test hole. If you're still confident...I guess go for it! If not, rent an excavator.

On last thing, can you dig and add coil(s) with these systems piece meal as you go along or does whole 600' need opened up with pipe installed at one time? Might be safer that way with extended time to open 600' of trench.

 

[millsan1]

I have a geo system. Are you sure 300' is going to be enough? Seems kind of light to me. Everything I have read and seen is more int he thousands of feet.

 

[Gofast]

Another option is to dig four 300’ 10” trenches. The advantage to that is you never have to get in the trench.
The pipe goes out 300’ you put two foot dirt back in the trench then the return pipe goes in the trench. Then you fill the trench back in.
Better system performance. My neighbor has a Mini excavator he would probably rent me. I would then use my tractor to fill the trenches back in.
I will do a test dig and decide.

We have Mini splits for heating and air right now. The digging can be spread over some time.

 

[buckeyefarmer]

Looks great how many ton unit did you put in? what MFG did you go with on the Geo unit?
How deep did you dig?

Comfort Aire units by heatcontrollers., same as climatemaster unit, same control boards.

I put in a 3ton and a 2 ton. One 70' trench per ton. Mine are 5' - 6' deep. Did one at a time, in parallel. Digging the next trench, piled top soil between trenches, then filled the other trench as i went.

 

[Gofast]

Is your system pressured how long have you had the system do you like it?

 

[ovrszd]

A trench 300' x 6' x 16" contains 2,400 cubic feet of dirt. That equals 89 cubic yards of dirt. An average tem wheeler dump truck will hold 11 cubic yards. That equals 8 dump truck loads.

So,,, do the math on your bucket and you can determine how many buckets it will take you. Estimate how long it takes to fill, swing, dump, return to the trench and you can get a ballpark idea. Add at least 10% because you will under estimate the time.

I think this will be multiple days. Many, many, many hours.

P.S. comparing a shallow trench is very deceiving.

 

[Gofast]

I like how you think.
If I used my 10” bucket 300’ * 6’ * 10” = 1500 cubic feet of dirt. 4 trenches 6,000 cubic feet of dirt.
222 cubic yards of dirt 20 dump trucks of dirt.

To be continued I need to see how much dirt the bucket holds.

I wounder if buying a Trencher Bucket would speed things up the pipe it only 3/4 inch.

 

[buckeyefarmer]

Another option is to dig four 300’ 10” trenches. The advantage to that is you never have to get in the trench.
The pipe goes out 300’ you put two foot dirt back in the trench then the return pipe goes in the trench. Then you fill the trench back in.
Better system performance. My neighbor has a Mini excavator he would probably rent me. I would then use my tractor to fill the trenches back in.
I will do a test dig and decide.

We have Mini splits for heating and air right now. The digging can be spread over some time.

300' straight pipe is way too little.

 

[ovrszd]

I like how you think.
If I used my 10” bucket 300’ * 6’ * 10” = 1500 cubic feet of dirt. 4 trenches 6,000 cubic feet of dirt.
222 cubic yards of dirt 20 dump trucks of dirt.

To be continued I need to see how much dirt the bucket holds.

I wounder if buying a Trencher Bucket would speed things up the pipe it only 3/4 inch.

Soil types vary soooo much. Here a 12" bucket is worthless unless we are in serious drought. Normal soil moisture conditions and it will be 75% packed with dirt after half a dozen dips. Then productivity really sails..... Away......

 

[Gofast]

I did a test dig and this is not going to happen with my 1710.
I can use it to dig close to the house and to the fence that is about 25’.

It will do great to fill the trench back in and level it out but there is no way it is going to do the whole dig.

It is 600’ per ton but I am going to put in 4 600’ loops. That is 600 foot more loop than is required.

Now I will either have to talk to my neighbor about renting his mini excavator.
or maybe have a track hoe with a 3’ bucket dig the two trenches instead of 4.
I will cover it all back up with my 1710.