chasdvorak
Well-known member
I ran into a problem this year as I prepared to winterize my coach and was unable to draw anti-freeze. Some troubleshooting revealed that the plastic handles on the 3 way valves (both of them), developed cracks at the base and would not turn the valves to the proper position. I discovered this situation as I attempted to blow out the lines and I was able to manually turn the valves to their proper position. Fortunately, I completed the winterization of the coach without further problems and am researching a fix for the valve handles. I have also discussed the issue with Jim Hutt, (57chevyconvt), who is a subject matter expert that graciously shared his knowledge .
I have had problems in the past with a flakey check valve and hot water going through the cold water faucets so I wanted to get a better idea of how the system works. I removed the walls of the basement, took some pictures and some detailed notes of the connections and various hoses. The system is less complicated to understand when you shrink all those hoses, valves and connectors into a diagram. I then prepared a diagram using PowerPoint (poor mans' Visio) which I have posted below as a .jpg (I also have a .ppt file if anyone is interested). Please review the diagram and advise if I have any errors or am missing something.
The short story is the two 3-way valves are used to route antifreeze through both the hot and cold water PEX lines while by-passing the hot water tank, thereby saving you the cost and hassle of filling the hot water tank with several gallons of antifreeze. Think of the valves as an either or situation. The bottom valve selects (via the pump) either water from there fresh water tank or anti-freeze from the suction hose in the UDC. The top valve selects a path for the cold water either into the hot water heater or around it. The check valve at the top of the hot water heater prevents any antifreeze from entering the tank, but allows hot water to flow out of the tank when the valve is set to the normal position.
I now understand that my issue involving the hot water on the cold side is caused by the lack of pressure (either city water or pump) on the water system. There is a considerable amount of water pressure (30-50 lbs), when the system is activated. When you shut off the city water or fresh water pump, there is a residual amount of pressure in the system which includes the pressure on the hot water tank. The system only has one check valve so it appears that the hot water can flow into the cold side (bottom of tank), if the city water feed and pump are turned off. I also think there might be some siphoning that occurs since the water is really hot and plentiful.
Jim Hutt also advised that it may be possible to mix the hot and cold water via the outside shower if you turn the faucets to the on position while having the wand in the off position. In other words, you are using the outside shower and you simply click off the nozzle without turning the faucets off. I recall doing that in the past and having issues with lukewarm water. Also, I did not notice any check valves on the outside shower fixture.
So…..I'm hoping this diagram and explanation help if you need to troubleshoot your system. The fix could be easy as turning the water on at its' source or checking the outside shower faucets. Once again, please advise if you see any errors or flaws since I have a limited amount of knowledge (just ask my wife).
Safe Travels,
Chuck
I have had problems in the past with a flakey check valve and hot water going through the cold water faucets so I wanted to get a better idea of how the system works. I removed the walls of the basement, took some pictures and some detailed notes of the connections and various hoses. The system is less complicated to understand when you shrink all those hoses, valves and connectors into a diagram. I then prepared a diagram using PowerPoint (poor mans' Visio) which I have posted below as a .jpg (I also have a .ppt file if anyone is interested). Please review the diagram and advise if I have any errors or am missing something.
The short story is the two 3-way valves are used to route antifreeze through both the hot and cold water PEX lines while by-passing the hot water tank, thereby saving you the cost and hassle of filling the hot water tank with several gallons of antifreeze. Think of the valves as an either or situation. The bottom valve selects (via the pump) either water from there fresh water tank or anti-freeze from the suction hose in the UDC. The top valve selects a path for the cold water either into the hot water heater or around it. The check valve at the top of the hot water heater prevents any antifreeze from entering the tank, but allows hot water to flow out of the tank when the valve is set to the normal position.
I now understand that my issue involving the hot water on the cold side is caused by the lack of pressure (either city water or pump) on the water system. There is a considerable amount of water pressure (30-50 lbs), when the system is activated. When you shut off the city water or fresh water pump, there is a residual amount of pressure in the system which includes the pressure on the hot water tank. The system only has one check valve so it appears that the hot water can flow into the cold side (bottom of tank), if the city water feed and pump are turned off. I also think there might be some siphoning that occurs since the water is really hot and plentiful.
Jim Hutt also advised that it may be possible to mix the hot and cold water via the outside shower if you turn the faucets to the on position while having the wand in the off position. In other words, you are using the outside shower and you simply click off the nozzle without turning the faucets off. I recall doing that in the past and having issues with lukewarm water. Also, I did not notice any check valves on the outside shower fixture.
So…..I'm hoping this diagram and explanation help if you need to troubleshoot your system. The fix could be easy as turning the water on at its' source or checking the outside shower faucets. Once again, please advise if you see any errors or flaws since I have a limited amount of knowledge (just ask my wife).
Safe Travels,
Chuck
