I give up................. There is a sensor in the pump that senses hot water, then closes the value and turns off the pump. All it did was pump the cold water laying in the hot water line into the cold water line. So therefore NO Hot water was pumped into the cold water line....
When the hot water reaches the
D'MAND System, a thermal sensor (thermistor) senses a temperature rise and quickly closes
the zone valve while it shuts the pump off. The sophisticated electronic circuitry that does
this is attached to the high-performance pump housing.
The Metlund D'MAND System can utilize the cold water line as a return line or use a
dedicated return line. By using the existing cold water line, it is easy to retrofit existing
homes or businesses. Special plumbing is not needed, and since the System will not allow for
hot water to cross over to the cold water line, all the cold water fixtures still have cold water.