System is Relentless

2/21/15

Solar kicked on at around 9:15.  Temp from tank was 78, return was 86. My wife took a shower.  I took a shower.  I turned the recirculation pump on at noon so we could wash the dishes in the dishwasher.  Up to now, we have needed to use the energy boost feature of the dishwasher because the water going to it wasn’t warm enough.  We have a “smart” dishwasher so if you set it to normal and the water isn’t hot enough, it switches to a pseudo energy boost.  Instead of running for 90 minutes, it runs for 168.  Energy boost runs for 132.

After circulating hot water through the house, we turned on the dishwasher to normal.  The water coming in was hot enough so it only ran for 90 minutes.  So far, so good.  Right after we turned on the dishwasher, the solar system stopped sending water to the roof collector.  It is cloudy today so the collector isn’t hot enough.  The last reading I took before the system shut down was tank temp = 83, collector temp = 91.  I hope the sun comes out so we can replace the water the dishwasher used.  Energystar dishwashers are only supposed to use 5.8 gallons of water.  Our GE uses only 3.8 per cycle.  That means we shouldn’t lose too much heat from water replacement in the hot water tank on this cloudy day.

The solar system goes off when it is cloudy but as soon as a bit of sun peeks through, it goes on again.  Fascinating.  It is such a simple design, but is relentless at getting the sun to heat the water.