Any GARNheads out there tried combining a GARN with solar? My specific question is whether the chemicals in the GARN would lead to buildup in the solar panels if one were to implement a drainback system?
gorbull said:May be a silly idea but what if you only half filled the GARN say 500-750 gals. for solar gain during the non-heating season?
afblue said:...if you have to use a heat exchanger to separate it from the Garn, you might as well make it a antifreeze system. The drain back tank adds expense but the biggest one is the fact that you need a large pump to initially overcome the startup head of a drainback system, which is a more expensive pump, and more electricity to run it.
Como said:Now if you have them anyway, well a different situation. I was just looking at the total investment cost new. And from a Carbon Footprint point of view I would be better burning wood.
The type of system I think depends more on your local situation that using the Garn. We have extreme cold but big fluctuations and high solar gain so what would work for me may not for you.
140F was on the basis of 120F at the tap, taking into account losses in the system.
Good luck. Let us know what the end result is, theory is one thing, actuality another.
afblue said:Since you already have the solar, I would plumb it goes directly to an indirect DHW tank, then just use the Garn tank as a heat dump, if it ever gets too hot. Ultimately what you are trying to do is get DHW as close to 100% of the time as possible, or potentially not have to fire the Garn for the longest time of the year possible, not quite saving wood. I am not an expert on efficiencies of solar systems, but if you have to use a heat exchanger to separate it from the Garn, you might as well make it a antifreeze system. The drain back tank adds expense but the biggest one is the fact that you need a large pump to initially overcome the startup head of a drainback system, which is a more expensive pump, and more electricity to run it.