Plumbing Suggestions for Solar Bypass?

[mas985]

You will know when water is flowing through the hose because the filter pressure will increase due to the extra head loss. A little pressure rise will result in little water going through the hose while a large pressure rise will result in more water going through the hose. If you want exact flow rates, that will be a little tricky but possible to calculate. If you want a visual indicator, then plumb a flow meter on the feed pipe to the hose. But choose one on the lower end of the scale because there will probably be little water flowing through the hose. But even with a bypass fully open, there will still be a trickle through the hose because there will always be a pressure differential between the input and output of the hose albeit a small one with the bypass fully open.

Also one thing to keep in mind is that the heat transfer efficiency from the cement to the hose is proportional to the flow rate through the hose. The higher the flow, the more heat that will be extracted from the cement. The lower the flow rate, the lower the heat transfer.

For example 1 GPM through a 1000' of 0.5" hose is going to be an extra 33.3' head loss and a 14 PSI filter pressure rise. That is going reduce the overall flow rate of the pump significantly and depending on the pump, may not even be possible. Not only that but 1 GPM through the hose will not extract much heat at all so it may be pointless. Ideally, the hose should arranged in multiple parallel loops much like a solar panel.

To get a pressure rise of only 6 PSI, the flow rate through the hose would need to be less than 0.6 GPM.