... below 40℃, it will flow out from cold port. When above 45℃, flow from hot port. When the temperature ... between 40—45℃, it will flow from both ports.Normally it is applied in solar heater ... system. When sun shine is short and water temp from solar geyser is not hot enough, the water will ... 3 years .8. If you need NPT thread , pls contact me , my factory can customized NPT thread