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[rosewood]

well as spring is around the corner,its got me thinking about my solar panel idea....never got to it last year....anyway here's the idea. when im done burning wood for the season,in middle or end of april i would use solar to heat water. the panel will be 4x8.using 2x6box,insulated 2''foam panel bottom,on top will be approx 75' of 5/8 copper tubing with alum absortion strips bonded to copper.all painted black under glass panels, panel will be mounted on roof of furnace positioned to face sun..etc  using a small taco 007 circulator to circ water in a loop from tank to panel and return also using temp gauges to monitor temp in /out of panel with ball valve controlling flo rate. maybe some fancy temp switch to turn on circ when panel temp reaches temp? any thoughts ? any experts on the matter?

[kjw58]

hey rosewood check out  Guy Marsden's web site I believe it is  arttec.net .  He has a laught of info on solar water heating and some good reading on solar heating.  He also makes and sells a temperature differential controller to do exactly what you want to do.   

[willieG]

no expert here not even a novice but i did see one a year or so ago that had his coil weaved back and forth and ALWAYS going up hill, he said he didn't a pump as long as his tank was lower than the panel. he said the hot water naturally rose as it warmed up and when it reached the top it would fall in the straight pipe back down to the top of the tank and cooler water would be siphoned up into the bottom of his  heating coil and on and on it went?

just something for you to maybe play with or think about

[RSI]

I would not use an 007 pump. A Grundfos 15-58 would be a much better choice. It is 3 speed and low will be more than enough flow and use less than half the electricity. (besides being a better pump)

What do you have for heating your hot water? If a sidearm, it probably won't get hot enough to do any good and might even pull heat out of the water heater. If you have a heat exchanger that pre-heats the water going into the tank then you should be able to save gas / electricity.

I would personally use black irrigation tubing because it would cost a small fraction of what the copper would cost.

[Bull]

I use the black plastic pipe, I have a coil (300 ft) that I put on my roof and hook to the pool in the spring. It raises the water temp about 30 degrees from inlet to outlet.

[RSI]

What flow rate is it with 30 degrees temp rise? (or what size pipe and pump?)

[Bull]

I use 1/2 inch pipe and a pond or fountain pump, not sure of the size.