Solar Water Behind a Window
First a quick back story: I live in Halifax, Nova Scotia, which to my knowledge is zone 5…? I’m getting condensation on my cold water pipes, where the pipes first enter my house from my well. In another question about this issue, Charlie Sullivan was kind enough to offer a suggestion of using a drain water heat recovery unit to preheat the cold water. Which, really is a great suggestion as it’s 100% passive.
I took a close look at the applicability of this in my home and while it would be feasible, it would be cost prohibitive at about $700 for a 30 inch model and a couple of fittings to install it. Also, the hot water isn’t used very often, whereas the cold water is used quit often.
While I was looking at the situation and how I would need to plumb everything I realized that the water lines pass over top of a window that serves basically no purpose to the aesthetics of my house. It’s behind the HRV, in a utility closet, facing away from the road. So I thought, if I made a solar water heater panel to fit behind the glazing area of the window (30×30) it would likely be enough to raise the temperature of the water that few degrees I need to avoid the condensation. To make it out of PEX tubing, with isolation valves on the inlet and outlet, as well as a bypass valve, and a temperature gauge on the outlet, I’d need about $50-60 on top of the parts I already have.
So, if you’ve made it this far into my ridiculous idea, here comes a barrage of questions.
1) Would it work?
2) Would I have to worry about freezing in the winter? The room is in a finished basement that is heated in the winter.
3) Would I need to worry about over heating in the summer?
4) My cost estimate is without using any kind of aluminum fins. This was for a couple of reasons, first of course, was to limit cost. But also I don’t think I’d need that level of efficiency to prevent condensation, and I don’t think it would be desirable to have the cold water, which comes in at about 5-6 C, any more than say 10 C.
5) What am I missing? I’m sure there’s something. 🙂
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