Concept for cold weather use of rPod water systems

the valve for recirculating hot water using the on board water pump is pictured.  The top valve is a normal closed valve that will be linked to an identical valve (not shown) at the rear of the pod at the rear kitchen.  these two valves are controlled via a thermostat to open when temps are near freezing and remain closed when temps are not close to freezing. the valves draw 30ma each to remain open, so they low energy and should be suitable for boondocking in colder weather.   The valve at the rear will be the mixing valve for the hot water to return via the cold water lines and dump into the fresh water tank via the overflow line when both valves are open and the third valve is closed (the valve at the bottom of the pic.). 

The valve at the bottom is a two wire reverse polarity ball valve that will be controlled by a DPDT switch mounted with the rest of the pod switches by the stereo panel.  This valve controls whether the fresh water flows normally (as in warm weather with cold/hot mixing at the point of use) or stops the cold water and then the other thermostatically controlled switches react to the temperature to open and close to circulate water to prevent freezing. This valve only uses power when opening or closing.  Once it reaches each state, it uses no power. the idea is to automate the cold weather function as best i can and be able to return to the normal configuration with ease.  Some of the valves are not easy to get to.  And, i still like the idea of having separate cold and hot water available when needed. 

I used pex fittings which are easy, but are not cheap.  They are nice in the tight settings that this has to be placed since they are simply push to connect.  more pics to come.