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On the losses: In practice, yes, probably not too bad. In theory, at least, with respect to the difference between theory and practice, the actual, measured loss rate may have more use as instructional. An R-10 tank insulation as the tank has from the factory, with an approx. exterior tank area of, say ~ 38 ft.^2 ought to give an as built tank U of ~ 3.8 BTU/hr.*deg. F. My measured value, including some local piping losses, and in spite of what are probably pretty heavy, bordering on absurd, insulation levels, and carful attention to sealing details, is still 2X that of the claimed as built loss rate. That, somewhat disappointing result seems to agree with my general observation and finding that a system's actual heat loss will be nowhere near what I think it will be, and commonly about 1/2 to 2/3 what a calculated value might be. I'm reasonably confident the reasons are many and varied. Long, boring conversation.
As for heat traps, yes. Out horizontal and ~ 18 " down and up for the tank to house line to the tempering valve, with the same in the return line from the collectors on the roof plus check valve on the collector line at the pump inlet. The mains cold inlet has the same with the inlet located via a T in the tank outlet line to the collectors near the tank entrance. There is also a branch from the pump outlet line back to the top of tank via one of the (now unused) anode connections) to enable tank recirculation. Both the line to the collectors and the recirc. line have rotometers and (calibrated) thermometers. Between those instruments and the Davis on the roof, I can estimates of the solar water heater performance under varying conditions. FWIW, the 2 SunEarth collectors plumbed in series seem to be performing better than OG-100 estimates, probably because I'm running water through them in series at a rate that gets me out of laminar flow through the collectors, with pump output valve throttled but up to ~ 4.5 G.P.M, but usually running at about 1.7 gpm. I also fiddled w/ the controller via var. resistors to get the coll. return temp. w/in a few tenths of a degree of the tank outlet to coll. temp. +/- a bit.
I had lots of fun designing that system.
As for heat traps, yes. Out horizontal and ~ 18 " down and up for the tank to house line to the tempering valve, with the same in the return line from the collectors on the roof plus check valve on the collector line at the pump inlet. The mains cold inlet has the same with the inlet located via a T in the tank outlet line to the collectors near the tank entrance. There is also a branch from the pump outlet line back to the top of tank via one of the (now unused) anode connections) to enable tank recirculation. Both the line to the collectors and the recirc. line have rotometers and (calibrated) thermometers. Between those instruments and the Davis on the roof, I can estimates of the solar water heater performance under varying conditions. FWIW, the 2 SunEarth collectors plumbed in series seem to be performing better than OG-100 estimates, probably because I'm running water through them in series at a rate that gets me out of laminar flow through the collectors, with pump output valve throttled but up to ~ 4.5 G.P.M, but usually running at about 1.7 gpm. I also fiddled w/ the controller via var. resistors to get the coll. return temp. w/in a few tenths of a degree of the tank outlet to coll. temp. +/- a bit.
I had lots of fun designing that system.
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