We have a Watts 120-160 mixing valve on our tankless water heater. I was wondering how these work exactly.
I know that cold water enters through the bottom of the valve, hot water enters through the side and the mixed water exits through the top closest to the dial. But what is actually happening inside? More importantly, what happens at full close/full open?
1) What I mean is if I set the valve at full 'hot' how much hot water flow is actually going through the valve? I would expect that even at full hot, some cold water is being mixed to temper the water to 160 degrees.
2) What happens with full cold water? Is it 100% cold or is 'cold' considered 120 degrees in this case, and hot water is still being mixed?
3) Does flow through hot/cold change as water temperature changes?
The reason I ask is that I have a flush/drain valve after the mixing valve, and I am trying to diagnose a flow problem. At full hot, the water coming from the hot water line after the mixing valve is not too much. Meaning very little flow through the heating coil. If I switch the valve to full cold, there is a nearly unrestricted flow out.