Plumb, Plumb, Plumb away.

With the pumping station and solar panels in place, all that remained was to get the hot water tank and piping in place and that is what I did.

  To make sure that the heat dump was well soldered, I put together a pressure test gauge as shown in the picture.

The gauge uses a tee that connects 1) pressure gauge, 2) tire valve stem, and 3) the pipe under test.  In this case I used "shark-bite" fittings from Home Depot.  The "shark-bite" fittings slide right on to the end of a pipe, but cannot be removed without a tool.  To check the integrity of the pipe, I filled the heat dump with compressed air.
     I found that overnight, there was some slight loss of pressure which was worrying.  So I decided to mostly fill the heat dump with water and then add air to create pressure.  This revealed that some leaking was occurring in the 1/4 NPT fittings.  Once I tightened the fittings, the leaking stopped.

    Plumbing is not difficult work, but it requires patience and attention to detail.  There is a lot of measuring, cutting, deburring, sanding, dry-fit, mark, disassemble, flux, solder, cool, clean, and repeat.  The parts have to be absolutely clean.  Flux needs to be applied to every square millimeter of both mating surfaces and solder must be applied to the full 360 degrees of the joint.
    The images below will give you a sense of the process for the return line for the solar panels.

    The first part of the piping required a 180 degree turn which I made with two "long radius" 1" copper elbows.  Those connected to the solar panels via a union (half) that was purchased from Heliodyne.  The union connects to the panel using an O-ring so that it can be disassembled easily.  I sloped the pipe leading to this area down in this direction.  If I need to drain the system I can just disconnect the union from the panel.  I considered adding a drain valve at this location, but I didn't.  

 That pipe connects to a second using a 90 degree long radius elbow.  These "long radius" elbows create dramatically less flow resistance than a standard elbows.  The pipe is then routed up at 45 degrees right underneath the panels.  I worked to minimize the visual impact of the piping by hiding them behind the panels.

 The pipe then transitions through a 45 degree elbow toward the house.

 

That pipe goes straight through the one of the holes in the sills.

 And then sticks into the basement.

 And curves down to the pumping station mounted on the wall.   The special high temperature/UV resistant UT Solaflex Insulation that I purchased from "Alt E" was not slit.  The insulation had to be slid onto the copper tubes which presented a bit of a logistics problem.  The joints in the 6' long insulation tubes had to be planned to be near solder joints.  The insulation could be compressed away from the jointed and held with a clamp during soldering.  To aid in installing the insulation, I applied baby power to the copper tubing and then slid the insulation onto the pipes.  The "long radius" elbows made it quite easy to make the insulation slide around the turns.  However, it is easy to poke your finger tip into the insulation, so I learned to work mostly with my palms.

 After soldering, the insulation could be pushed back into position.

 That should give you a better sense of the plumbing process.  The same process was repeated for the supply line to the solar panels and then connections made to the heat dump and the hot water tank.

   Speaking of the hot water tank, there is my buddy Doug dropping it off at my house.  Better go help him unload it.