you've got me thinking about trying this with my pv array. Mine is capable of 280w peak (when new), so maybe I could get better use of the power this way than feeding back into the grid with my 200 watt inverter like I do now. Hmmm, I'll have to do some calculating. The only cost for me to try, is some type of heating element. Heck, I might even have something that will work for surface mount already.
I need to price propane, we only fill once a year since we burn lots of wood, but my back problems are quickly changing that
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As far as I know, My boiler doesn't try to maintain a set internal water temp when in standby. So it doesn't use the main burner unless a zone calls for it. There are times in warm weather when the gage is showing a pretty low water temp. The standing pilot probably keeps some heat in it
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