I bought a house with an OWB three years ago and I'm losing almost 15 degrees of heat between the furnace and the house. The lines leave the house and the OWB in pvc pipe, the install was about 12 years ago and so I have to assume they didn't insulate the lines. My summer project is to dig them up and insulate them. Given the fact that 15 x 2 = 30 degrees of heat is lost to the ground every time the water leaves the OWB and returns, I'm looking forward to saving some wood and getting my gas bills down to 30 bucks a month (right now a gas boiler supplements the OWB).
I'd like to hear some thoughts on my current plan. Rather than replace all the lines, what I want to do is expose the old pvc, then slide larger sections of tongue and groove pvc pipe over the top of the old pvc. These new sections will be 5 or 6" diameter, with 2 or 3 pre-drilled holes in each section large enough to fit a spray foam nozzle. I'll center the new sections of pvc on the old, then fill them with spray foam, so the old pvc containing the pex lines will be completely encased in spray foam.
I haven't priced out the tongue and groove pvc, but I'm assuming they will be cheaper than buying the same length of insulated pex tubing. It will be a painstaking process digging alongside and under the old pvc once we expose it with the excavator, but if my labor saves me money then so be it - I've got a 16 year old nephew on summer vacation and the way I see things, it will be good for his work ethic.
Any thoughts on this would be much appreciated.
I'd like to hear some thoughts on my current plan. Rather than replace all the lines, what I want to do is expose the old pvc, then slide larger sections of tongue and groove pvc pipe over the top of the old pvc. These new sections will be 5 or 6" diameter, with 2 or 3 pre-drilled holes in each section large enough to fit a spray foam nozzle. I'll center the new sections of pvc on the old, then fill them with spray foam, so the old pvc containing the pex lines will be completely encased in spray foam.
I haven't priced out the tongue and groove pvc, but I'm assuming they will be cheaper than buying the same length of insulated pex tubing. It will be a painstaking process digging alongside and under the old pvc once we expose it with the excavator, but if my labor saves me money then so be it - I've got a 16 year old nephew on summer vacation and the way I see things, it will be good for his work ethic.
Any thoughts on this would be much appreciated.