Hi. Does anyone use a decoiler for installing "racetrack" horizontals? Adam

We have built a multitude of machines for de coiling geo pipe 2" and up. Never for the smaller stuff. Leaving it out in the sun prior to installing should do the trick for your application.
Eric

Pros....why isn't slinkies used exclusively in horizontal  systems?

Heat capacity of the ground is significantly better with only 2' of pipe per foot of trench with a racetrack as opposed to 6' of pipe per foot of trench with slinkies.
While slinkies require less trench, they require more pipe. If excavation is cheap (or free) and real estate isn't a problem, a racetrack may be the better value.

mtrent, many of the race track guys are installing 6 pipe which is worse than a 6'/foot slinky because it has a shallower mean depth if all other things are equal.
To your question Robin, slinkies are harder to transport if you wish to build them off sight.

Southline I see most who use race tracks unrolling in the trench as they go.

I have a couple of reasons for the question. 1- I am wondering if I can limit the dangers/liability of rolling cold pipe in muddy trenches by limiting the time in the trench. 2- by decoiling it may be possible to somewhat straighten the pipe to increase flow. I installed a loop with a field tiler(sp)last year and noticed an increase in flow assuming it was due to the straight pipe.

Posted By mtrentw on 20 Aug 2014 07:33 AM
Heat capacity of the ground is significantly better with only 2' of pipe per foot of trench with a racetrack as opposed to 6' of pipe per foot of trench with slinkies.
While slinkies require less trench, they require more pipe. If excavation is cheap (or free) and real estate isn't a problem, a racetrack may be the better value.

Do you have any data to back up your statements? The heat capacity of the ground does not change, what changes might be the surface area for heat exchange. I would argue that every single design, wether it is slinky, racetrack or straight trenches, can be made to perform equally depending on the design. Your heatpump does not know where the water comes from. It comes down to who can install the best performance for the best overall price, including excavation, material costs, pressure drop and labor (time).
Having a job with more expensive prevailing labor rates might change the approach, where you invest more into the material.

One of the appeals of slinkies is limited trench time.

Yes we used to have a nice heavy duty un-coiler we made for the pipe, you can see it in this video at about 2 minutes and 12 seconds...https://www.youtube.com/watch?v=tb4SqkcP_Eg It disappeared from a job, so we had a few Malco pex-uncoilers that we modified and uncoil pipe with...the trick is to put a piece of plywood on bottom and top of pipe to keep it tight

I was a bit loose on terminology, so I do agree with you. Heat capacity of the ground does not change. The density of the heat exchange area is the variable. Many ways to skin a cat and it is up to the designer to get it right.

So.. I took some time and built a decoiler and used it yesterday. Success! The 600' rolls of 3/4 came off the roll straight and we were not covered head to toe in wet clay. Definitely less time in the trenches. Adam