Good Morning Everyone.
Denis LeBlanc from Ontario. I have a 16x24 greenhouse that is unheated. Inside I have an insulated grow bed that essentially is a self irrigating planter box with 80 gal. of water with drain tile lining the bottom as well as a 4" pvc tile. The pvc holds apr 25 gallons of water. I'd like to connect that pvc pipe to a 3x6ft hot water solar panel to put some heat into the grow bed thereby preventing freezing.
I'm just trying to keep the temp above 36F to keep the plants in a vegetative state to keep growing..
The issue is to have a pump in the water system that will not freeze without having a second system in place, like heat tape, to keep everything from freezing.
I wanted to install a low flow pump but having the system as a draw down, or open loop means the pump would also have to drain back to the bed to prevent freeze damage, but the pump would also have to be able to draw water up about 12-16" from the garden bed.
The only work around I see is installing a submersible pump inside the 4" pvc pipe where it would get some protection from freeze up..
Does anyone have another suggestions as to how this might work..
The entire system is water based in case there is a leak into the grow bed..
I can provide some diagrams and pictures if this would clarify this project build..