Jesse Coker wrote:Hello all! Wondering if anyone has done this or feels they can speak on this approach we are considering. Our plan is to house a wood boiler that can heat water that is pumped through Pex tubing and back through a closed system. We are likely to lay the tubing down 12 inches and space it 18 inches apart. Tubing will likely be 5/8" to 3/4" diameter.
My question isn't so much about our ability to run the system, but rather about its effectiveness as it is running. Will the heat that is produced reach the root systems of things like tomatoes? We do plan on laying some sort of insulation beneath the tubing to direct the heat where we want it. I would much rather lay it deep like this so that we don't have worry about hitting the lines as we work the soil.
Also, we will incorporate a 300 gallon tank for storing the heat produced in the water as we circulate.
We have already installed about fifty 55-gallon steel barrels on the inside perimeter of our 30'x72' high tunnel and filled them with water for insulation from outside soil temperatures, as well as to moderate temps inside the greenhouse.
Thanks for your thoughts!! -Jesse
Coog Kelly wrote:
Heat always rises........... Heat will penetrate downwards some too. This includes geo-thermal heat. With your buried barrels. it does not sound like you have this option.
Dig down at least a foot around the perimeter of the GH. 9 feet away. lay down 2" styro SM and bury that too. Have your tubing run outside of the GH also. Geothermal will help warm the ground around the outside as well and you won't have cool GH perimeter. The frost will not penetrate the ground around the GH. This extra might not be huge in RI, but in the Grt White North it makes a big Diff....