Mixing Valve

[BulldogAcres]

I have a flat plate heat exchanger that exchanges the boiler hot water to heating and domestic hot water. The water leaving the heat exchanger is 150 degrees F. The return water is around 80 degrees F. Would I gain anything by using a mixing valve to mix the 150 degree F water with the return 80 degree F water. The 150 degree water has heated the house and two out buildings and supplied domestic hot water even at below zero temperatures with no problems. If I put a mixing valve after the heat exchanger and mixed it with the return 80 degree F water, would I gain anything by lowering the heating and domestic hot water to 120 degrees F. I know 150 degree F domestic hot water is dangerous, but I live alone and have adjusted knowing not to turn the hot water on without the cold.

 

[Dune]

Do you ever have guests? 150 hot water isn't just dangerous, it is ilegal.

 

[Hunderliggur]

Seems to be a common thread this morning. TEMPER IT! Do you need 150F supply for your heat? If so, temper your DHW only.

 

[bigburner]

The tank temperature is only limited by the T&P & input, the out put should to be tempered to about 120. These valves are considered to hot water extender's allows mixing of cooler water to give more usable water. PS only the shower water is required to be tempered, but 150 is no a great idea.