Progress

I'm not finding much time in the week to work on this, but I've made good progress nonetheless.  Most of the downstairs plumbing is completed.  The plumbing that is hooked into the house water supply is all sweated together and in operation.   The solar storage tank is now passing unheated water to the water heater.  All it needs now is have the solar heat exchange fluid (distilled water) pumped through it's heat exchanger.

The combination of short work windows and the need for hot water in the house made for some stressful times. I created a few leaks that were hard to put right.  Calling my friend Colin the Plumber was the right thing to do.  It was expensive, but I learned a lot watching him work.

Here's a incomplete list of mistakes I made:

1. I sweated in two swing check valves.  They sweated into the system no problem.  Every time the washing machine demanded hot water with it's solenoid actuated valves it caused the swing valves to bang really loudly.  I would never suggest to anyone to use this type of valve.  Colin replaced them with valves that close quietly.
2. I failed to read the instructions for plumbing in the Watts tempering valve.  On the cold inlet side you HAVE to have 8" to 12" of pipe coming up vertically into the valve body for it to work.  If you don't do that you only get cold water.  None of the hot supply is passed.  This is probably a good way to fail as passing solar heated 175 deg. water would be really bad.  However, it caused me to call in a plumber in the night to put in a ball valve on the cold supply side of tempering valve, until time could be found to plumb it correctly.  This was an expensive, stupid mistake.
3. You should always use PTFE tape on pipe threads WITH pipe compound.  Tape first, then apply a generous amount of pipe compound.  I'll never go back to using only PTFE tape...
4. I did not use two unions on the top of the SunEarth tank.  To begin with, I used none.  Because I had a leak on the pipe nipple on the inlet side (See mistake #3), I fixed that and put in a union.  The other side is not leaking and had no union, so when it comes to time replace the tank, it will need to be cut out.  At that time a union should be installed.
5. I used a pressure relief valve that I had laying around on the solar storage tank, not the 210F PRV that was supplied by Solartrope.  That probably won't be a problem, but we will see....

Whew!  This phase of the project was Trial by Leaks!  I always want the second or third iteration of whatever it is I'm making, so I expected mistakes...

Solar Storage, Pump, Drainback Tank

The solar collector loop is still unattached on the roof.  It's sweated together in the garage and presumably I could test it by pumping water up to the rooftop.  It wouldn't be a full pressure test, but it would be interesting to see if the pump is capable of lifting the water up there.  I'll be pretty grumpy if it's not.

There's lots left to do, but the hardest bits are done.  The biggest deal is racking the panels.  That I hope to do in the next couple weeks.  If all the plumbing leaks are over and done with (big if), then most of the rest of the work is insulating pipes, hooking up the controller, and lots of little things. Little is good =)

Hot Water Heater, Tempering and Other Valves